Astronomers have used mysterious fast radio bursts to solve a decades-old mystery of 'missing matter', long predicted to exist in the Universe but never detected -- until now.
The researchers have now found all of the missing 'normal' matter in the vast space between stars and galaxies, as detailed today in the journal Nature.
Lead author Associate Professor Jean-Pierre Macquart, from the Curtin University node of the International Centre for Radio Astronomy Research (ICRAR), said astronomers have been searching for the missing matter for almost thirty years.
"We know from measurements of the Big Bang how much matter there was in the beginning of the Universe," he said.
"But when we looked out into the present Universe, we couldn't find half of what should be there. It was a bit of an embarrassment."
"Intergalactic space is very sparse," he said. "The missing matter was equivalent to only one or two atoms in a room the size of an average office."
"So it was very hard to detect this matter using traditional techniques and telescopes."
The researchers were able to directly detect the missing matter using the phenomenon known as fast radio bursts -- brief flashes of energy that appear to come from random directions in the sky and last for just milliseconds.
Scientists don't yet know what causes them but it must involve incredible energy, equivalent to the amount released by the Sun in 80 years. They have been difficult to detect as astronomers don't know when and where to look for them.
Associate Professor Macquart said the team detected the missing matter by using fast radio bursts as "cosmic weigh stations."
"The radiation from fast radio bursts gets spread out by the missing matter in the same way that you see the colours of sunlight being separated in a prism," he said.
"We've now been able to measure the distances to enough fast radio bursts to determine the density of the Universe," he said. "We only needed six to find this missing matter."
The missing matter in this case is baryonic or 'normal' matter -- like the protons and neutrons that make up stars, planets and you and me.
It's different from dark matter, which remains elusive and accounts for about 85 per cent of the total matter in the Universe.
Co-author Professor J. Xavier Prochaska, from UC Santa Cruz, said we have unsuccessfully searched for this missing matter with our largest telescopes for more than 20 years.
"The discovery of fast radio bursts and their localisation to distant galaxies were the key breakthroughs needed to solve this mystery," he said.
Associate Professor Ryan Shannon, another co-author from Swinburne University of Technology, said the key was the telescope used, CSIRO's Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope.
"ASKAP both has a wide field of view, about 60 times the size of the full Moon, and can image in high resolution," he said. "This means that we can catch the bursts with relative ease and then pinpoint locations to their host galaxies with incredible precision.
"When the burst arrives at the telescope, it records a live action replay within a fraction of a second," said Dr Keith Bannister from Australia's national science agency, CSIRO, who designed the pulse capture system used in this research.
"This enables the precision to determine the location of the fast radio burst to the width of a human hair held 200m away," he said.
Associate Professor Macquart said the research team had also pinned down the relationship between how far away a fast radio burst is and how the burst spreads out as it travels through the Universe.
"We've discovered the equivalent of the Hubble-Lemaitre Law for galaxies, only for fast radio bursts," he said.
"The Hubble-Lemaitre Law, which says the more distant a galaxy from us, the faster it is moving away from us, underpins all measurements of galaxies at cosmological distances."
The fast radio bursts used in the study were discovered using ASKAP, which is located at the Murchison Radio-astronomy Observatory in outback Western Australia. The international team involved in the discovery included astronomers from Australia, the United States and Chile.
Read more at Science Daily
May 30, 2020
Yes, your dog wants to rescue you
What to do. You're a dog. Your owner is trapped in a box and is crying out for help. Are you aware of his despair? If so, can you set him free? And what's more, do you really want to?
That's what Joshua Van Bourg and Clive Wynne wanted to know when they gave dogs the chance to rescue their owners.
Until recently, little research has been done on dogs' interest in rescuing humans, but that's what humans have come to expect from their canine companions -- a legend dating back to Lassie and updated by the popular Bolt.
"It's a pervasive legend," said Van Bourg, a graduate student in Arizona State University's Department of Psychology.
Simply observing dogs rescuing someone doesn't tell you much, Van Bourg said. "The difficult challenge is figuring out why they do it."
So, Van Bourg and Wynne, an ASU professor of psychology and director of the Canine Science Collaboratory at ASU, set up an experiment assessing 60 pet dogs' propensity to rescue their owners. None of the dogs had training in such an endeavor.
In the main test, each owner was confined to a large box equipped with a light-weight door, which the dog could move aside. The owners feigned distress by calling out "help," or "help me."
Beforehand, the researchers coached the owners so their cries for help sounded authentic. In addition, owners weren't allowed to call their dog's name, which would encourage the dog to act out of obedience, and not out of concern for her owner's welfare.
"About one-third of the dogs rescued their distressed owner, which doesn't sound too impressive on its own, but really is impressive when you take a closer look," Van Bourg said.
That's because two things are at stake here. One is the dogs' desire to help their owners, and the other is how well the dogs understood the nature of the help that was needed. Van Bourg and Wynne explored this factor in control tests -- tests that were lacking in previous studies.
In one control test, when the dog watched a researcher drop food into the box, only 19 of the 60 dogs opened the box to get the food. More dogs rescued their owners than retrieved food.
"The key here is that without controlling for each dog's understanding of how to open the box, the proportion of dogs who rescued their owners greatly underestimates the proportion of dogs who wanted to rescue their owners," Van Bourg said.
"The fact that two-thirds of the dogs didn't even open the box for food is a pretty strong indication that rescuing requires more than just motivation, there's something else involved, and that's the ability component," Van Bourg said. "If you look at only those 19 dogs that showed us they were able to open the door in the food test, 84% of them rescued their owners. So, most dogs want to rescue you, but they need to know how."
In another control test, Van Bourg and Wynne looked at what happened when the owner sat inside the box and calmly read aloud from a magazine. What they found was that four fewer dogs, 16 out of 60, opened the box in the reading test than in the distress test.
"A lot of the time it isn't necessarily about rescuing," Van Bourg said. "But that doesn't take anything away from how special dogs really are. Most dogs would run into a burning building just because they can't stand to be apart from their owners. How sweet is that? And if they know you're in distress, well, that just ups the ante."
The fact that dogs did open the box more often in the distress test than in the reading control test indicated that rescuing could not be explained solely by the dogs wanting to be near their owners.
The researchers also observed each dog's behavior during the three scenarios. They noted behaviors that can indicate stress, such as whining, walking, barking and yawning.
"During the distress test, the dogs were much more stressed," Van Bourg said. "When their owner was distressed, they barked more, and they whined more. In fact, there were eight dogs who whined, and they did so during the distress test. Only one other dog whined, and that was for food."
What's more, the second and third attempts to open the box during the distress test didn't make the dogs less stressed than they were during the first attempt. That was in contrast to the reading test, where dogs that have already been exposed to the scenario, were less stressed across repeated tests.
"They became acclimated," Van Bourg said. "Something about the owner's distress counteracts this acclimation. There's something about the owner calling for help that makes the dogs not get calmer with repeated exposure."
In essence, these individual behaviors are more evidence of "emotional contagion," the transmission of stress from the owner to the dog, explains Van Bourg, or what humans would call empathy.
"What's fascinating about this study," Wynne said, "is that it shows that dogs really care about their people. Even without training, many dogs will try and rescue people who appear to be in distress -- and when they fail, we can still see how upset they are. The results from the control tests indicate that dogs who fail to rescue their people are unable to understand what to do -- it's not that they don't care about their people.
Read more at Science Daily
That's what Joshua Van Bourg and Clive Wynne wanted to know when they gave dogs the chance to rescue their owners.
Until recently, little research has been done on dogs' interest in rescuing humans, but that's what humans have come to expect from their canine companions -- a legend dating back to Lassie and updated by the popular Bolt.
"It's a pervasive legend," said Van Bourg, a graduate student in Arizona State University's Department of Psychology.
Simply observing dogs rescuing someone doesn't tell you much, Van Bourg said. "The difficult challenge is figuring out why they do it."
So, Van Bourg and Wynne, an ASU professor of psychology and director of the Canine Science Collaboratory at ASU, set up an experiment assessing 60 pet dogs' propensity to rescue their owners. None of the dogs had training in such an endeavor.
In the main test, each owner was confined to a large box equipped with a light-weight door, which the dog could move aside. The owners feigned distress by calling out "help," or "help me."
Beforehand, the researchers coached the owners so their cries for help sounded authentic. In addition, owners weren't allowed to call their dog's name, which would encourage the dog to act out of obedience, and not out of concern for her owner's welfare.
"About one-third of the dogs rescued their distressed owner, which doesn't sound too impressive on its own, but really is impressive when you take a closer look," Van Bourg said.
That's because two things are at stake here. One is the dogs' desire to help their owners, and the other is how well the dogs understood the nature of the help that was needed. Van Bourg and Wynne explored this factor in control tests -- tests that were lacking in previous studies.
In one control test, when the dog watched a researcher drop food into the box, only 19 of the 60 dogs opened the box to get the food. More dogs rescued their owners than retrieved food.
"The key here is that without controlling for each dog's understanding of how to open the box, the proportion of dogs who rescued their owners greatly underestimates the proportion of dogs who wanted to rescue their owners," Van Bourg said.
"The fact that two-thirds of the dogs didn't even open the box for food is a pretty strong indication that rescuing requires more than just motivation, there's something else involved, and that's the ability component," Van Bourg said. "If you look at only those 19 dogs that showed us they were able to open the door in the food test, 84% of them rescued their owners. So, most dogs want to rescue you, but they need to know how."
In another control test, Van Bourg and Wynne looked at what happened when the owner sat inside the box and calmly read aloud from a magazine. What they found was that four fewer dogs, 16 out of 60, opened the box in the reading test than in the distress test.
"A lot of the time it isn't necessarily about rescuing," Van Bourg said. "But that doesn't take anything away from how special dogs really are. Most dogs would run into a burning building just because they can't stand to be apart from their owners. How sweet is that? And if they know you're in distress, well, that just ups the ante."
The fact that dogs did open the box more often in the distress test than in the reading control test indicated that rescuing could not be explained solely by the dogs wanting to be near their owners.
The researchers also observed each dog's behavior during the three scenarios. They noted behaviors that can indicate stress, such as whining, walking, barking and yawning.
"During the distress test, the dogs were much more stressed," Van Bourg said. "When their owner was distressed, they barked more, and they whined more. In fact, there were eight dogs who whined, and they did so during the distress test. Only one other dog whined, and that was for food."
What's more, the second and third attempts to open the box during the distress test didn't make the dogs less stressed than they were during the first attempt. That was in contrast to the reading test, where dogs that have already been exposed to the scenario, were less stressed across repeated tests.
"They became acclimated," Van Bourg said. "Something about the owner's distress counteracts this acclimation. There's something about the owner calling for help that makes the dogs not get calmer with repeated exposure."
In essence, these individual behaviors are more evidence of "emotional contagion," the transmission of stress from the owner to the dog, explains Van Bourg, or what humans would call empathy.
"What's fascinating about this study," Wynne said, "is that it shows that dogs really care about their people. Even without training, many dogs will try and rescue people who appear to be in distress -- and when they fail, we can still see how upset they are. The results from the control tests indicate that dogs who fail to rescue their people are unable to understand what to do -- it's not that they don't care about their people.
Read more at Science Daily
May 29, 2020
ESPRESSO confirms the presence of an Earth around the nearest star
The existence of a planet the size of Earth around the closest star in the solar system, Proxima Centauri, has been confirmed by an international team of scientists including researchers from the University of Geneva (UNIGE). The results, which you can read all about in the journal Astronomy & Astrophysics, reveal that the planet in question, Proxima b, has a mass of 1.17 earth masses and is located in the habitable zone of its star, which it orbits in 11.2 days. This breakthrough has been possible thanks to radial velocity measurements of unprecedented precision using ESPRESSO, the Swiss-manufactured spectrograph -- the most accurate currently in operation -- which is installed on the Very Large Telescope in Chile. Proxima b was first detected four years ago by means of an older spectrograph, HARPS -- also developed by the Geneva-based team -- which measured a low disturbance in the star's speed, suggesting the presence of a companion.
The ESPRESSO spectrograph has performed radial velocity measurements on the star Proxima Centauri, which is only 4.2 light-years from the Sun, with an accuracy of 30 centimetres a second (cm/s) or about three times more precise than that obtained with HARPS, the same type of instrument but from the previous generation.
"We were already very happy with the performance of HARPS, which has been responsible for discovering hundreds of exoplanets over the last 17 years," begins Francesco Pepe, a professor in the Astronomy Department in UNIGE's Faculty of Science and the man in charge of ESPRESSO. "We're really pleased that ESPRESSO can produce even better measurements, and it's gratifying and just reward for the teamwork lasting nearly 10 years."
Alejandro Suarez Mascareño, the article's main author, adds: "Confirming the existence of Proxima b was an important task, and it's one of the most interesting planets known in the solar neighbourhood."
The measurements performed by ESPRESSO have clarified that the minimum mass of Proxima b is 1.17 earth masses (the previous estimate was 1.3) and that it orbits around its star in only 11.2 days.
"ESPRESSO has made it possible to measure the mass of the planet with a precision of over one-tenth of the mass of Earth," says Michel Mayor, winner of the Nobel Prize for Physics in 2019, honorary professor in the Faculty of Science and the 'architect' of all ESPRESSO-type instruments. "It's completely unheard of."
And what about life in all this?
Although Proxima b is about 20 times closer to its star than the Earth is to the Sun, it receives comparable energy, so that its surface temperature could mean that water (if there is any) is in liquid form in places and might, therefore, harbour life.
Having said that, although Proxima b is an ideal candidate for biomarker research, there is still a long way to go before we can suggest that life has been able to develop on its surface. In fact, the Proxima star is an active red dwarf that bombards its planet with X rays, receiving about 400 times more than the Earth.
"Is there an atmosphere that protects the planet from these deadly rays?" asks Christophe Lovis, a researcher in UNIGE's Astronomy Department and responsible for ESPRESSO's scientific performance and data processing. "And if this atmosphere exists, does it contain the chemical elements that promote the development of life (oxygen, for example)? How long have these favourable conditions existed? We're going to tackle all these questions, especially with the help of future instruments like the RISTRETTO spectrometer, which we're going to build specially to detect the light emitted by Proxima b, and HIRES, which will be installed on the future ELT 39 m giant telescope that the European Southern Observatory (ESO) is building in Chile."
Surprise: is there a second planet?
In the meantime, the precision of the measurements made by ESPRESSO could result in another surprise. The team has found evidence of a second signal in the data, without being able to establish the definitive cause behind it. "If the signal was planetary in origin, this potential other planet accompanying Proxima b would have a mass less than one third of the mass of the Earth. It would then be the smallest planet ever measured using the radial velocity method," adds Professor Pepe.
Read more at Science Daily
The ESPRESSO spectrograph has performed radial velocity measurements on the star Proxima Centauri, which is only 4.2 light-years from the Sun, with an accuracy of 30 centimetres a second (cm/s) or about three times more precise than that obtained with HARPS, the same type of instrument but from the previous generation.
"We were already very happy with the performance of HARPS, which has been responsible for discovering hundreds of exoplanets over the last 17 years," begins Francesco Pepe, a professor in the Astronomy Department in UNIGE's Faculty of Science and the man in charge of ESPRESSO. "We're really pleased that ESPRESSO can produce even better measurements, and it's gratifying and just reward for the teamwork lasting nearly 10 years."
Alejandro Suarez Mascareño, the article's main author, adds: "Confirming the existence of Proxima b was an important task, and it's one of the most interesting planets known in the solar neighbourhood."
The measurements performed by ESPRESSO have clarified that the minimum mass of Proxima b is 1.17 earth masses (the previous estimate was 1.3) and that it orbits around its star in only 11.2 days.
"ESPRESSO has made it possible to measure the mass of the planet with a precision of over one-tenth of the mass of Earth," says Michel Mayor, winner of the Nobel Prize for Physics in 2019, honorary professor in the Faculty of Science and the 'architect' of all ESPRESSO-type instruments. "It's completely unheard of."
And what about life in all this?
Although Proxima b is about 20 times closer to its star than the Earth is to the Sun, it receives comparable energy, so that its surface temperature could mean that water (if there is any) is in liquid form in places and might, therefore, harbour life.
Having said that, although Proxima b is an ideal candidate for biomarker research, there is still a long way to go before we can suggest that life has been able to develop on its surface. In fact, the Proxima star is an active red dwarf that bombards its planet with X rays, receiving about 400 times more than the Earth.
"Is there an atmosphere that protects the planet from these deadly rays?" asks Christophe Lovis, a researcher in UNIGE's Astronomy Department and responsible for ESPRESSO's scientific performance and data processing. "And if this atmosphere exists, does it contain the chemical elements that promote the development of life (oxygen, for example)? How long have these favourable conditions existed? We're going to tackle all these questions, especially with the help of future instruments like the RISTRETTO spectrometer, which we're going to build specially to detect the light emitted by Proxima b, and HIRES, which will be installed on the future ELT 39 m giant telescope that the European Southern Observatory (ESO) is building in Chile."
Surprise: is there a second planet?
In the meantime, the precision of the measurements made by ESPRESSO could result in another surprise. The team has found evidence of a second signal in the data, without being able to establish the definitive cause behind it. "If the signal was planetary in origin, this potential other planet accompanying Proxima b would have a mass less than one third of the mass of the Earth. It would then be the smallest planet ever measured using the radial velocity method," adds Professor Pepe.
Read more at Science Daily
In planet formation, it's location, location, location
Astronomers using NASA's Hubble Space Telescope are finding that planets have a tough time forming in the rough-and-tumble central region of the massive, crowded star cluster Westerlund 2. Located 20,000 light-years away, Westerlund 2 is a unique laboratory to study stellar evolutionary processes because it's relatively nearby, quite young, and contains a large stellar population.
A three-year Hubble study of stars in Westerlund 2 revealed that the precursors to planet-forming disks encircling stars near the cluster's center are mysteriously devoid of large, dense clouds of dust that in a few million years could become planets.
However, the observations show that stars on the cluster's periphery do have the immense planet-forming dust clouds embedded in their disks. Researchers think our solar system followed this recipe when it formed 4.6 billion years ago.
So why do some stars in Westerlund 2 have a difficult time forming planets while others do not? It seems that planet formation depends on location, location, location. The most massive and brightest stars in the cluster congregate in the core, which is verified by observations of other star-forming regions. The cluster's center contains at least 30 extremely massive stars, some weighing up to 80 times the mass of the Sun. Their blistering ultraviolet radiation and hurricane-like stellar winds of charged particles blowtorch disks around neighboring lower-mass stars, dispersing the giant dust clouds.
"Basically, if you have monster stars, their energy is going to alter the properties of the disks around nearby, less massive stars," explained Elena Sabbi, of the Space Telescope Science Institute in Baltimore and lead researcher of the Hubble study. "You may still have a disk, but the stars change the composition of the dust in the disks, so it's harder to create stable structures that will eventually lead to planets. We think the dust either evaporates away in 1 million years, or it changes in composition and size so dramatically that planets don't have the building blocks to form."
The Hubble observations represent the first time that astronomers analyzed an extremely dense star cluster to study which environments are favorable to planet formation. Scientists, however, are still debating whether bulky stars are born in the center or whether they migrate there. Westerlund 2 already has massive stars in its core, even though it is a comparatively young, 2-million-year-old system.
Using Hubble's Wide Field Camera 3, the researchers found that of the nearly 5,000 stars in Westerlund 2 with masses between 0.1 to 5 times the Sun's mass, 1,500 of them show fluctuations in their light as the stars accrete material from their disks. Orbiting material clumped within the disk would temporarily block some of the starlight, causing brightness fluctuations.
However, Hubble detected the signature of such orbiting material only around stars outside the cluster's packed central region. The telescope witnessed large drops in brightness for as much as 10 to 20 days around 5% of the stars before they returned to normal brightness. They did not detect these dips in brightness in stars residing within four light-years of the center. These fluctuations could be caused by large clumps of dust passing in front of the star. The clumps would be in a disk tilted nearly edge-on to the view from Earth. "We think they are planetesimals or structures in formation," Sabbi explained. "These could be the seeds that eventually lead to planets in more evolved systems. These are the systems we don't see close to very massive stars. We see them only in systems outside the center."
Thanks to Hubble, astronomers can now see how stars are accreting in environments that are like the early universe, where clusters were dominated by monster stars. So far, the best known nearby stellar environment that contains massive stars is the starbirth region in the Orion Nebula. However, Westerlund 2 is a richer target because of its larger stellar population.
"Hubble's observations of Westerlund 2 give us a much better sense of how stars of different masses change over time, and how powerful winds and radiation from very massive stars affect nearby lower-mass stars and their disks," Sabbi said. "We see, for example, that lower-mass stars, like our Sun, that are near extremely massive stars in the cluster still have disks and still can accrete material as they grow. But the structure of their disks (and thus their planet-forming capability) seems to be very different from that of disks around stars forming in a calmer environment farther away from the cluster core. This information is important for building models of planet formation and stellar evolution."
This cluster will be an excellent laboratory for follow-up observations with NASA's upcoming James Webb Space Telescope, an infrared observatory. Hubble has helped astronomers identify the stars that have possible planetary structures. With Webb, researchers can study which disks around stars are not accreting material and which disks still have material that could build up into planets. This information on 1,500 stars will allow astronomers to map a path on how star systems grow and evolve. Webb also can study the chemistry of the disks in different evolutionary phases and watch how they change, and help astronomers determine what influence environment plays in their evolution.
Read more at Science Daily
A three-year Hubble study of stars in Westerlund 2 revealed that the precursors to planet-forming disks encircling stars near the cluster's center are mysteriously devoid of large, dense clouds of dust that in a few million years could become planets.
However, the observations show that stars on the cluster's periphery do have the immense planet-forming dust clouds embedded in their disks. Researchers think our solar system followed this recipe when it formed 4.6 billion years ago.
So why do some stars in Westerlund 2 have a difficult time forming planets while others do not? It seems that planet formation depends on location, location, location. The most massive and brightest stars in the cluster congregate in the core, which is verified by observations of other star-forming regions. The cluster's center contains at least 30 extremely massive stars, some weighing up to 80 times the mass of the Sun. Their blistering ultraviolet radiation and hurricane-like stellar winds of charged particles blowtorch disks around neighboring lower-mass stars, dispersing the giant dust clouds.
"Basically, if you have monster stars, their energy is going to alter the properties of the disks around nearby, less massive stars," explained Elena Sabbi, of the Space Telescope Science Institute in Baltimore and lead researcher of the Hubble study. "You may still have a disk, but the stars change the composition of the dust in the disks, so it's harder to create stable structures that will eventually lead to planets. We think the dust either evaporates away in 1 million years, or it changes in composition and size so dramatically that planets don't have the building blocks to form."
The Hubble observations represent the first time that astronomers analyzed an extremely dense star cluster to study which environments are favorable to planet formation. Scientists, however, are still debating whether bulky stars are born in the center or whether they migrate there. Westerlund 2 already has massive stars in its core, even though it is a comparatively young, 2-million-year-old system.
Using Hubble's Wide Field Camera 3, the researchers found that of the nearly 5,000 stars in Westerlund 2 with masses between 0.1 to 5 times the Sun's mass, 1,500 of them show fluctuations in their light as the stars accrete material from their disks. Orbiting material clumped within the disk would temporarily block some of the starlight, causing brightness fluctuations.
However, Hubble detected the signature of such orbiting material only around stars outside the cluster's packed central region. The telescope witnessed large drops in brightness for as much as 10 to 20 days around 5% of the stars before they returned to normal brightness. They did not detect these dips in brightness in stars residing within four light-years of the center. These fluctuations could be caused by large clumps of dust passing in front of the star. The clumps would be in a disk tilted nearly edge-on to the view from Earth. "We think they are planetesimals or structures in formation," Sabbi explained. "These could be the seeds that eventually lead to planets in more evolved systems. These are the systems we don't see close to very massive stars. We see them only in systems outside the center."
Thanks to Hubble, astronomers can now see how stars are accreting in environments that are like the early universe, where clusters were dominated by monster stars. So far, the best known nearby stellar environment that contains massive stars is the starbirth region in the Orion Nebula. However, Westerlund 2 is a richer target because of its larger stellar population.
"Hubble's observations of Westerlund 2 give us a much better sense of how stars of different masses change over time, and how powerful winds and radiation from very massive stars affect nearby lower-mass stars and their disks," Sabbi said. "We see, for example, that lower-mass stars, like our Sun, that are near extremely massive stars in the cluster still have disks and still can accrete material as they grow. But the structure of their disks (and thus their planet-forming capability) seems to be very different from that of disks around stars forming in a calmer environment farther away from the cluster core. This information is important for building models of planet formation and stellar evolution."
This cluster will be an excellent laboratory for follow-up observations with NASA's upcoming James Webb Space Telescope, an infrared observatory. Hubble has helped astronomers identify the stars that have possible planetary structures. With Webb, researchers can study which disks around stars are not accreting material and which disks still have material that could build up into planets. This information on 1,500 stars will allow astronomers to map a path on how star systems grow and evolve. Webb also can study the chemistry of the disks in different evolutionary phases and watch how they change, and help astronomers determine what influence environment plays in their evolution.
Read more at Science Daily
Children's temperament traits affect their motor skills
A recent study among 3- to 7-year-old children showed that children's motor skills benefitted if a child was older and participated in organised sports. Additionally, the study provided information about the importance of temperament traits for motor skills. More specifically, traits such as activity and attention span persistence were found to be positively associated with motor skills. This was a rather novel result, as the association between motor skills and temperament during early childhood is not yet widely understood.
In essence, motor skills comprise locomotor, ball and balance skills, all of which are present in everyday life tasks like running, climbing, throwing and drawing. Adequate motor skills enable participation in typical games and types of playing for different ages and developmental phases, for example, in tag, running and ball games.
"Even though motor skills develop as a function of age, skill development still needs to be stimulated consciously," says Donna Niemistö, a PhD student from the Faculty of Sport and Health Sciences, University of Jyväskylä. "Motor skills do not develop without practising, thus skills need reinforcement through repetition of the skills. Motor skill development is greatly supported when the child is moving in multiple ways. In a current study we found more evidence that participation in organised sports can be useful to gain more opportunities to practise and repeat essential movements."
Temperament and its traits refer to a child's biological and individual characteristics, such as the biological way of reacting to one's surroundings. Temperament is rather stable over time. To date, there have been only a handful of studies concerning young children's motor skills and temperament traits, even though in older age groups, more research is already available.
"Children who tend to have an active type of temperament, as well as children who show persistency when faced with challenges can be motivated and persistent in learning and rehearsing motor tasks. Therefore, these findings were expected and logical. A child with an active temperament can react more rapidly. Consequently, the child will get more opportunities to move along with increased repetitions. Without noticing, the child will also gain more opportunities to perform motor tasks."
Additionally, the capacity to maintain attention is equally important for skill acquisition.
"To learn new skills, one must be able to concentrate and maintain focus even though the skill may, at first, feel challenging or even difficult," continues Niemistö.
Both temperament traits can influence the development of motor skills. Therefore, it is important that parents as well as early educators and teachers are aware of these individual factors in case they want to encourage and support their children's motor skill development.
"For example, there is no need to emphasize for an active child to be more active," Niemistö explains. "However, with an active child, a parent could guide the child to maintain focus and attention, despite possible distractions in the surroundings."
Motor skills were assessed with two internationally well-known measurements. The first assessment tool measured the locomotor and ball skills and the second one the balance and coordination skills of the child. As the chosen assessment tools measured divergent aspects of motor development, differences between associated factors related to motor skills were also found.
"The development of balance and coordination skills was better in those children who were described as more emotionally regulated," says Niemistö. "On the other hand, locomotor skills were better in children whose parents had higher educational level and the development of ball skills benefitted if children had free access to sport facilities in nearby surroundings."
Read more at Science Daily
In essence, motor skills comprise locomotor, ball and balance skills, all of which are present in everyday life tasks like running, climbing, throwing and drawing. Adequate motor skills enable participation in typical games and types of playing for different ages and developmental phases, for example, in tag, running and ball games.
"Even though motor skills develop as a function of age, skill development still needs to be stimulated consciously," says Donna Niemistö, a PhD student from the Faculty of Sport and Health Sciences, University of Jyväskylä. "Motor skills do not develop without practising, thus skills need reinforcement through repetition of the skills. Motor skill development is greatly supported when the child is moving in multiple ways. In a current study we found more evidence that participation in organised sports can be useful to gain more opportunities to practise and repeat essential movements."
Temperament and its traits refer to a child's biological and individual characteristics, such as the biological way of reacting to one's surroundings. Temperament is rather stable over time. To date, there have been only a handful of studies concerning young children's motor skills and temperament traits, even though in older age groups, more research is already available.
"Children who tend to have an active type of temperament, as well as children who show persistency when faced with challenges can be motivated and persistent in learning and rehearsing motor tasks. Therefore, these findings were expected and logical. A child with an active temperament can react more rapidly. Consequently, the child will get more opportunities to move along with increased repetitions. Without noticing, the child will also gain more opportunities to perform motor tasks."
Additionally, the capacity to maintain attention is equally important for skill acquisition.
"To learn new skills, one must be able to concentrate and maintain focus even though the skill may, at first, feel challenging or even difficult," continues Niemistö.
Both temperament traits can influence the development of motor skills. Therefore, it is important that parents as well as early educators and teachers are aware of these individual factors in case they want to encourage and support their children's motor skill development.
"For example, there is no need to emphasize for an active child to be more active," Niemistö explains. "However, with an active child, a parent could guide the child to maintain focus and attention, despite possible distractions in the surroundings."
Motor skills were assessed with two internationally well-known measurements. The first assessment tool measured the locomotor and ball skills and the second one the balance and coordination skills of the child. As the chosen assessment tools measured divergent aspects of motor development, differences between associated factors related to motor skills were also found.
"The development of balance and coordination skills was better in those children who were described as more emotionally regulated," says Niemistö. "On the other hand, locomotor skills were better in children whose parents had higher educational level and the development of ball skills benefitted if children had free access to sport facilities in nearby surroundings."
Read more at Science Daily
Survey identifies learning opportunities related to health impacts of climate change
An international survey of Global Consortium on Climate and Health Education (GCCHE) membership found that the majority of members -- health professions schools and programs, including medical, nursing, and public health -- offer learning opportunities related to the health impacts of climate change, yet many also encountered challenges in instituting or developing curricula. The results of the survey provide a baseline assessment of the state of climate-health education internationally among health professions institutions. Results of the survey by Columbia University Mailman School of Public Health researchers appear in the journal JAMA Network Open.
The survey suggests there exist a range of educational offerings on climate-health, including sessions, courses, programs, or post-doctoral positions. Some schools have offered climate-health education for several years, some are just now adding content, and others do not include any content on the subject. While many schools are discussing adding climate-health educational offerings, there are still considerable gaps in offerings at many institutions as well as challenges that extend beyond the institutional level, such as political and funding priorities that might lead to lack of staff time and materials to support the training.
Conducted in 2017 and 2018, the survey was completed by 84 health professions institutions internationally. Among respondents, 63% offer climate-health education, most commonly as part of a required core course (76%). Sixty-one of 82 respondents (74%) reported additional climate-health offerings are under discussion, 42 of 59 (71%) encountered some challenges trying to institute the curriculum, and most have received a positive response to adding content mainly from students (39 of 58 (67%)), faculty (35 of 58 (60%)), and administration (23 of 58 (40%)).
The article's authors write that opportunities exist to facilitate the integration of climate-health curricula, such as working with students, faculty, and members of administration that are interested in this topic. In order to facilitate this integration, institutions can look to online resources, groups, and networks to provide guidance and information to develop curricula.
"We suggest that health professions schools include this content in their curricula and that awareness as well as financial support, resources, and expertise increase to help in its uptake," write study authors Brittany Shea, MA, Kim Knowlton, DrPH, and Jeffrey Shaman, PhD. "Climate change may be affecting health in a variety of ways with increasing consequences. Health professionals, including those in public health, nursing, and medical services, should be educated on how to prevent, mitigate, and respond to factors associated with climate change that may be associated with health in a negative way."
Read more at Science Daily
The survey suggests there exist a range of educational offerings on climate-health, including sessions, courses, programs, or post-doctoral positions. Some schools have offered climate-health education for several years, some are just now adding content, and others do not include any content on the subject. While many schools are discussing adding climate-health educational offerings, there are still considerable gaps in offerings at many institutions as well as challenges that extend beyond the institutional level, such as political and funding priorities that might lead to lack of staff time and materials to support the training.
Conducted in 2017 and 2018, the survey was completed by 84 health professions institutions internationally. Among respondents, 63% offer climate-health education, most commonly as part of a required core course (76%). Sixty-one of 82 respondents (74%) reported additional climate-health offerings are under discussion, 42 of 59 (71%) encountered some challenges trying to institute the curriculum, and most have received a positive response to adding content mainly from students (39 of 58 (67%)), faculty (35 of 58 (60%)), and administration (23 of 58 (40%)).
The article's authors write that opportunities exist to facilitate the integration of climate-health curricula, such as working with students, faculty, and members of administration that are interested in this topic. In order to facilitate this integration, institutions can look to online resources, groups, and networks to provide guidance and information to develop curricula.
"We suggest that health professions schools include this content in their curricula and that awareness as well as financial support, resources, and expertise increase to help in its uptake," write study authors Brittany Shea, MA, Kim Knowlton, DrPH, and Jeffrey Shaman, PhD. "Climate change may be affecting health in a variety of ways with increasing consequences. Health professionals, including those in public health, nursing, and medical services, should be educated on how to prevent, mitigate, and respond to factors associated with climate change that may be associated with health in a negative way."
Read more at Science Daily
May 27, 2020
Clues to COVID-19 in the brain uncovered in new study
A study by University of Cincinnati researchers and four Italian institutions reviewing neuroimaging and neurological symptoms in patients with COVID-19 may shed light on the virus's impact on the central nervous system.
The findings, published in the journal Radiology, reveal that altered mental status and stroke are the most common neurological symptoms in COVID-19 patients, which authors say could help physicians notice "red flags" earlier.
"Studies have described the spectrum of chest imaging features of COVID-19, but only a few case reports have described COVID-19 associated neuroimaging findings," says lead author Abdelkader Mahammedi, MD, assistant professor of radiology at UC and a UC Health neuroradiologist. "To date, this is the largest and first study in literature that characterizes the neurological symptoms and neuroimaging features in COVID-19 patients. These newly discovered patterns could help doctors better and sooner recognize associations with COVID-19 and possibly provide earlier interventions."
Researchers in this study investigated neurological symptoms and imaging findings in patients from three major institutions in Italy: University of Brescia, Brescia; University of Eastern Piedmont, Novara; and University of Sassari, Sassari. Italy was the second epicenter of the spread of COVID-19, resulting in over 30,000 deaths.
The study included images from 725 hospitalized patients with confirmed COVID-19 infection between Feb. 29 and April 4. Of these, 108 (15%) had serious neurological symptoms and underwent brain or spine imaging. Most patients (99%) had brain CT scans, while 16% had head and neck CT imaging and 18% had brain MRI.
Investigators found that 59% of patients reported an altered mental state and 31% experienced stroke, which were the most common neurological symptoms. Patients also experienced headache (12%), seizure (9%) and dizziness (4%), among other symptoms.
"Of these 108 patients, 31, or 29%, had no known past medical history. Of these, aged 16 to 62 years, 10 experienced stroke and two had brain bleeds," Mahammedi says. "Seventy-one, or 66%, of these patients had no findings on a brain CT, out of which 7 of them (35%) brain MRI showed abnormalities."
He adds that altered mental status was more common in older adults.
While results show that the neuroimaging features of patients with COVID-19 vary, and an altered mental status and stroke are the most prevalent in patients, Mahammedi says this study reveals that there are other conditions to be on the lookout for.
Read more at Science Daily
The findings, published in the journal Radiology, reveal that altered mental status and stroke are the most common neurological symptoms in COVID-19 patients, which authors say could help physicians notice "red flags" earlier.
"Studies have described the spectrum of chest imaging features of COVID-19, but only a few case reports have described COVID-19 associated neuroimaging findings," says lead author Abdelkader Mahammedi, MD, assistant professor of radiology at UC and a UC Health neuroradiologist. "To date, this is the largest and first study in literature that characterizes the neurological symptoms and neuroimaging features in COVID-19 patients. These newly discovered patterns could help doctors better and sooner recognize associations with COVID-19 and possibly provide earlier interventions."
Researchers in this study investigated neurological symptoms and imaging findings in patients from three major institutions in Italy: University of Brescia, Brescia; University of Eastern Piedmont, Novara; and University of Sassari, Sassari. Italy was the second epicenter of the spread of COVID-19, resulting in over 30,000 deaths.
The study included images from 725 hospitalized patients with confirmed COVID-19 infection between Feb. 29 and April 4. Of these, 108 (15%) had serious neurological symptoms and underwent brain or spine imaging. Most patients (99%) had brain CT scans, while 16% had head and neck CT imaging and 18% had brain MRI.
Investigators found that 59% of patients reported an altered mental state and 31% experienced stroke, which were the most common neurological symptoms. Patients also experienced headache (12%), seizure (9%) and dizziness (4%), among other symptoms.
"Of these 108 patients, 31, or 29%, had no known past medical history. Of these, aged 16 to 62 years, 10 experienced stroke and two had brain bleeds," Mahammedi says. "Seventy-one, or 66%, of these patients had no findings on a brain CT, out of which 7 of them (35%) brain MRI showed abnormalities."
He adds that altered mental status was more common in older adults.
While results show that the neuroimaging features of patients with COVID-19 vary, and an altered mental status and stroke are the most prevalent in patients, Mahammedi says this study reveals that there are other conditions to be on the lookout for.
Read more at Science Daily
Children may not always grow out of being picky eaters
If your preschooler often pushes their dinner plate away or wages battles against taking another bite of a vegetable they don't like, they may not grow out of it anytime soon.
By age four, children could be established picky eaters, a new study suggests. And the more parents try to control and restrict children's diets, the more finicky they may become, according to findings published in Pediatrics.
"Picky eating is common during childhood and parents often hear that their children will eventually 'grow out of it.' But that's not always the case," says senior author Megan Pesch, M.D., a developmental behavioral pediatrician at Michigan Medicine C.S. Mott Children's Hospital.
But there's a silver lining for worried parents -- while fussy eaters have a lower body mass index, most are still in the healthy range and not underweight, researchers found. They may also be less likely to be overweight or experience obesity than peers.
"We still want parents to encourage varied diets at young ages, but our study suggests that they can take a less controlling approach," Pesch says. That being said "we need more research to better understand how children's limited food choices impact healthy weight gain and growth long term."
The study followed 317 mother-child pairs from low-income homes over a four-year period. Families reported on children's eating habits and mothers' behaviors and attitudes about feeding when children were four, five, six, eight and nine.
Picky eating was stable from preschool to school-age, indicating that any attempts to expand food preferences may need to occur in toddler or preschool years to be most effective. High picky eating was associated with lower BMIs and low picky eating was associated with higher BMIs.
The pickiest eaters also were often associated with increased pressure to eat and restriction on certain types of foods. This reinforces previous Mott-led research suggesting that pressuring children to eat foods they dislike won't lead to a well-rounded diet later in life or encourage better health or development.
Certain child characteristics, including sex, birth order, and socioeconomic status, also have been associated with persistence of picky eating.
"We found that children who were pickier had mothers who reported more restriction of unhealthy foods and sweets," Pesch says. "These mothers of picky eaters may be trying to shape their children's preferences for more palatable and selective diets to be more healthful. But it may not always have the desired effect."
Read more at Science Daily
By age four, children could be established picky eaters, a new study suggests. And the more parents try to control and restrict children's diets, the more finicky they may become, according to findings published in Pediatrics.
"Picky eating is common during childhood and parents often hear that their children will eventually 'grow out of it.' But that's not always the case," says senior author Megan Pesch, M.D., a developmental behavioral pediatrician at Michigan Medicine C.S. Mott Children's Hospital.
But there's a silver lining for worried parents -- while fussy eaters have a lower body mass index, most are still in the healthy range and not underweight, researchers found. They may also be less likely to be overweight or experience obesity than peers.
"We still want parents to encourage varied diets at young ages, but our study suggests that they can take a less controlling approach," Pesch says. That being said "we need more research to better understand how children's limited food choices impact healthy weight gain and growth long term."
The study followed 317 mother-child pairs from low-income homes over a four-year period. Families reported on children's eating habits and mothers' behaviors and attitudes about feeding when children were four, five, six, eight and nine.
Picky eating was stable from preschool to school-age, indicating that any attempts to expand food preferences may need to occur in toddler or preschool years to be most effective. High picky eating was associated with lower BMIs and low picky eating was associated with higher BMIs.
The pickiest eaters also were often associated with increased pressure to eat and restriction on certain types of foods. This reinforces previous Mott-led research suggesting that pressuring children to eat foods they dislike won't lead to a well-rounded diet later in life or encourage better health or development.
Certain child characteristics, including sex, birth order, and socioeconomic status, also have been associated with persistence of picky eating.
"We found that children who were pickier had mothers who reported more restriction of unhealthy foods and sweets," Pesch says. "These mothers of picky eaters may be trying to shape their children's preferences for more palatable and selective diets to be more healthful. But it may not always have the desired effect."
Read more at Science Daily
Genomic analysis in samples of Neanderthals and modern humans shows a decrease in ADHD-associated genetic variants
The frequency of genetic variants associated with attention-deficit/hyperactivity disorder (ADHD) has decreased progressively in the evolutionary human lineage from the Palaeolithic to the present day, according to a study published in the journal Scientific Reports.
The new genomic analysis compares several ADHD-associated genetic variants described in current European populations to assess its evolution in samples of the human species (Homo sapiens), modern and ancient, and in samples of Neanderthals (Homo neanderthalensis). According to the conclusions, the low tendency observed in European populations could not be explained for the genetic mix with African populations or the introgression of Neanderthal genomic segments in our genome.
The new genomic study isled by Professor Bru Cormand, from the Faculty of Biology and the Institute of Biomedicine of the University of Barcelona (IBUB), the Research Institute Sant Joan de Déu (IRSJD) and the Rare Diseases Networking Biomedical Research Centre (CIBERER), and the researcher Oscar Lao, from the Centro Nacional de Análisis Genómico (CNAG), part of the Centre for Genomic Regulation (CRG). The study, whose first author is the CNAG-CRG researcher Paula Esteller -- current doctoral student at the Institute of Evolutionary Biology (IBE, CSIC-UPF) -- counts on the participation of research groups of the Aarhus University (Denmark) and the Upstate Medical University of New York (United States).
ADHD: an adaptive value in the evolutionary lineage of humans?
The attention deficit/hyperactivity disorder (ADHD) is an alteration of the neurodevelopment which can have a large impact on the life of the affected people. Featured by hyperactivity, impulsiveness and attention deficit, it is very common in modern populations -- with a prevalence of 5% in children and adolescents -- and can last up to adulthood.
From an evolutionary perspective, one would expect that anything detrimental would disappear among the population. In order to explain this phenomenon, several natural hypotheses have been presented, specifically focused on the context of transition from the Palaeolithic to the Neolithic, such as the known Mismatch Theory.
"According to this theory, cultural and technological changes that occurred over the last thousands of years would have allowed us to modify our environment in order to adopt it to our physiological needs in the short term. However, in the long term, these changes would have promoted an imbalance regarding the environment in which our hunter-gatherer ancestors evolved," note the authors.
Therefore, several traits like hyperactivity and impulsiveness -- typical in people with ADHD -- could have been selectively favoured in ancestral environments dominated by a nomad lifestyle. However, the same features would have become non-adaptive in other environments related to more recent times (mostly sedentary).
Why is it one of the most common disorders in children and adolescents?
The new study, based on the study on 20,000 ADHD affected people and 35,000 controls, reveals the genetic variants and alleles associated with ADHD tend to be found in genes which are intolerant to mutations that cause loss of function, which shows the existence of a selective pressure on this phenotype.
According to the authors, the high prevalence of ADHD nowadays could be a result from a favourable selection that took place in the past. Although being an unfavourable phenotype in the new environmental context, the prevalence would still be high because much time has not passed for it to disappear. However, due to the absence of available genomic data for ADHD, none of the hypothesis has been empirically contrasted so far.
Read more at Science Daily
The new genomic analysis compares several ADHD-associated genetic variants described in current European populations to assess its evolution in samples of the human species (Homo sapiens), modern and ancient, and in samples of Neanderthals (Homo neanderthalensis). According to the conclusions, the low tendency observed in European populations could not be explained for the genetic mix with African populations or the introgression of Neanderthal genomic segments in our genome.
The new genomic study isled by Professor Bru Cormand, from the Faculty of Biology and the Institute of Biomedicine of the University of Barcelona (IBUB), the Research Institute Sant Joan de Déu (IRSJD) and the Rare Diseases Networking Biomedical Research Centre (CIBERER), and the researcher Oscar Lao, from the Centro Nacional de Análisis Genómico (CNAG), part of the Centre for Genomic Regulation (CRG). The study, whose first author is the CNAG-CRG researcher Paula Esteller -- current doctoral student at the Institute of Evolutionary Biology (IBE, CSIC-UPF) -- counts on the participation of research groups of the Aarhus University (Denmark) and the Upstate Medical University of New York (United States).
ADHD: an adaptive value in the evolutionary lineage of humans?
The attention deficit/hyperactivity disorder (ADHD) is an alteration of the neurodevelopment which can have a large impact on the life of the affected people. Featured by hyperactivity, impulsiveness and attention deficit, it is very common in modern populations -- with a prevalence of 5% in children and adolescents -- and can last up to adulthood.
From an evolutionary perspective, one would expect that anything detrimental would disappear among the population. In order to explain this phenomenon, several natural hypotheses have been presented, specifically focused on the context of transition from the Palaeolithic to the Neolithic, such as the known Mismatch Theory.
"According to this theory, cultural and technological changes that occurred over the last thousands of years would have allowed us to modify our environment in order to adopt it to our physiological needs in the short term. However, in the long term, these changes would have promoted an imbalance regarding the environment in which our hunter-gatherer ancestors evolved," note the authors.
Therefore, several traits like hyperactivity and impulsiveness -- typical in people with ADHD -- could have been selectively favoured in ancestral environments dominated by a nomad lifestyle. However, the same features would have become non-adaptive in other environments related to more recent times (mostly sedentary).
Why is it one of the most common disorders in children and adolescents?
The new study, based on the study on 20,000 ADHD affected people and 35,000 controls, reveals the genetic variants and alleles associated with ADHD tend to be found in genes which are intolerant to mutations that cause loss of function, which shows the existence of a selective pressure on this phenotype.
According to the authors, the high prevalence of ADHD nowadays could be a result from a favourable selection that took place in the past. Although being an unfavourable phenotype in the new environmental context, the prevalence would still be high because much time has not passed for it to disappear. However, due to the absence of available genomic data for ADHD, none of the hypothesis has been empirically contrasted so far.
Read more at Science Daily
Increased fertility for women with Neanderthal gene, study suggests
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| DNA abstract illustration |
"The progesterone receptor is an example of how favourable genetic variants that were introduced into modern humans by mixing with Neandertals can have effects in people living today," says Hugo Zeberg, researcher at the Department of Neuroscience at Karolinska Institutet and the Max Planck Institute for Evolutionary Anthropology, who performed the study with colleagues Janet Kelso and Svante Pääbo.
Progesterone is a hormone, which plays an important role in the menstrual cycle and in pregnancy. Analyses of biobank data from more than 450,000 participants -- among them 244,000 women -- show that almost one in three women in Europe have inherited the progesterone receptor from Neandertals. Twenty-nine percent carry one copy of the Neandertal receptor and three percent have two copies.
Favourable effect on fertility
"The proportion of women who inherited this gene is about ten times greater than for most Neandertal gene variants," says Hugo Zeberg. "These findings suggest that the Neandertal variant of the receptor has a favourable effect on fertility."
The study shows that women who carry the Neandertal variant of the receptor tend to have fewer bleedings during early pregnancy, fewer miscarriages, and give birth to more children. Molecular analyses revealed that these women produce more progesterone receptors in their cells, which may lead to increased sensitivity to progesterone and protection against early miscarriages and bleeding.
Read more at Science Daily
May 26, 2020
Cultural diversity in chimpanzees
The transmission of cultures from generation-to-generation is only found in a few species besides humans. Chimpanzees are one such species and exhibit a large diversity of cultural and tool use behaviours. Although these behaviours have been well documented at a handful of long term research sites, the true cultural repertoire of chimpanzees across populations is still poorly understood. To better understand this diversity, researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, initiated the 'Pan African Programme: The Cultured Chimpanzee' (PanAf) in 2010. Using a standardized protocol, researchers set up camera traps, collected samples and recorded ecological data at over 40 temporary and long-term research sites across Africa.
Prior to this study, termite fishing was thought to occur in only two forms with one or multiple tools, from either above-ground or underground termite nests. By carefully observing the techniques required to termite fish at ten different sites, lead author Christophe Boesch created a catalogue of behaviours (ethogram) for each chimpanzee in the study.
What was found was 38 different technical elements making up the various termite fishing techniques, all of which were combined in different ways in each of the chimpanzee communities. In addition, individuals in the same community shared more of the termite fishing technical elements, and unique combinations of the technical elements, when compared to chimpanzees from other groups.
Surprising diversity
"The diversity of techniques seen in chimpanzee termite fishing was a huge surprise to me. Not only does each community have a very unique way of fishing, they also combine a number of different elements into specific termite fishing etiquettes," explains Christophe Boesch."The most striking examples of this are how the Wonga Wongue chimpanzees of Gabon usually lie down on their sides to termite fish, while the Korup chimpanzees in Cameroon lean on their elbows, and the ones from Goualougo in the Republic of Congo sit while fishing."
Because the communities of chimpanzees live in similar habitats with access to the same resources, ecological differences could mostly be ruled out to explain the observed differences. "This supports the idea that chimpanzees are capable of imitating social techniques in 'how to termite fish' which goes beyond alternative explanations such as each individual reinventing termite fishing each time they learn it," explains co-author Ammie Kalan.
Conforming to the group
Much like in human etiquette, not everything is about increased efficiency but rather about conforming to what the rest of the group is doing. In humans, this is observed in the different chopstick cultures across Asia. "For example, in Thailand and Japan not only are chopsticks somehow shaped differently, but the way they hold them differ as well, and this is very reminiscent of what we see here with chimpanzees. In La Belgique in Cameroon, chimpanzees fashion their stick by opening the fibers to obtain a long brush and then rest the termite-covered stick on their wrist while they eat. On the other hand, at another site in Cameroon called Korup, the chimpanzees do not make a brush at all and use their mouth to shake the inserted stick while it is in the mound," explains Christophe Boesch.
In humans, cultural variation has been documented in hundreds of different populations which is one explanation for why chimpanzee culture seems so limited in comparison. "What we knew before about chimpanzees came from at most 15 communities," notes co-author Hjalmar Kuehl. "Through the PanAf we have been able to study many more communities and by this we are able to learn more about the richness of chimpanzee diversity and culture and could demonstrate that there is so much more to discover out there."
Read more at Science Daily
Prior to this study, termite fishing was thought to occur in only two forms with one or multiple tools, from either above-ground or underground termite nests. By carefully observing the techniques required to termite fish at ten different sites, lead author Christophe Boesch created a catalogue of behaviours (ethogram) for each chimpanzee in the study.
What was found was 38 different technical elements making up the various termite fishing techniques, all of which were combined in different ways in each of the chimpanzee communities. In addition, individuals in the same community shared more of the termite fishing technical elements, and unique combinations of the technical elements, when compared to chimpanzees from other groups.
Surprising diversity
"The diversity of techniques seen in chimpanzee termite fishing was a huge surprise to me. Not only does each community have a very unique way of fishing, they also combine a number of different elements into specific termite fishing etiquettes," explains Christophe Boesch."The most striking examples of this are how the Wonga Wongue chimpanzees of Gabon usually lie down on their sides to termite fish, while the Korup chimpanzees in Cameroon lean on their elbows, and the ones from Goualougo in the Republic of Congo sit while fishing."
Because the communities of chimpanzees live in similar habitats with access to the same resources, ecological differences could mostly be ruled out to explain the observed differences. "This supports the idea that chimpanzees are capable of imitating social techniques in 'how to termite fish' which goes beyond alternative explanations such as each individual reinventing termite fishing each time they learn it," explains co-author Ammie Kalan.
Conforming to the group
Much like in human etiquette, not everything is about increased efficiency but rather about conforming to what the rest of the group is doing. In humans, this is observed in the different chopstick cultures across Asia. "For example, in Thailand and Japan not only are chopsticks somehow shaped differently, but the way they hold them differ as well, and this is very reminiscent of what we see here with chimpanzees. In La Belgique in Cameroon, chimpanzees fashion their stick by opening the fibers to obtain a long brush and then rest the termite-covered stick on their wrist while they eat. On the other hand, at another site in Cameroon called Korup, the chimpanzees do not make a brush at all and use their mouth to shake the inserted stick while it is in the mound," explains Christophe Boesch.
In humans, cultural variation has been documented in hundreds of different populations which is one explanation for why chimpanzee culture seems so limited in comparison. "What we knew before about chimpanzees came from at most 15 communities," notes co-author Hjalmar Kuehl. "Through the PanAf we have been able to study many more communities and by this we are able to learn more about the richness of chimpanzee diversity and culture and could demonstrate that there is so much more to discover out there."
Read more at Science Daily
Babies know when you imitate them -- and like it
Six-month old infants recognize when adults imitate them, and perceive imitators as more friendly, according to a new study from Lund University in Sweden. The babies looked and smiled longer at an adult who imitated them, as opposed to when the adult responded in other ways. Babies also approached them more, and engaged in imitating games. The research is published in PLOS One.
In the study, a researcher met 6-month old babies in their homes and played with them in four different ways. The researcher either: imitated everything the babies did as a mirror, or as a reverse mirror, imitated only the bodily actions of the babies while keeping an immobile face, or responded with a different action when the babies acted. The latter is called contingent responding and is how most parents would respond to their baby -- when the baby does or needs something, you react accordingly.
The researchers found that the babies looked and smiled longer, and tried to approach the adult more often, during the close mirroring of their actions.
"Imitating young infants seems to be an effective way to catch their interest and bond with them. The mothers were quite surprised to see their infants joyfully engaging in imitation games with a stranger, but also impressed by the infants' behaviours," says Gabriela-Alina Sauciuc, researcher at Lund University and main author of the study.
There was also much testing behavior during imitation. For example, if the baby hit the table and the researcher imitated that action, the baby would then hit the table several times, while carefully watching the researcher's responses. Even when the researcher did not show any emotions at all while imitating, the babies still seemed to recognize that they were being imitated -- and still responded with testing behavior.
"This was quite interesting. When someone actively tests the person who is imitating them, it is usually seen as an indication that the imitated individual is aware that there is a correspondence between their own behaviour and the behaviour of the other," Sauciuc says.
Scientists have long speculated that, through frequent exposure to being imitated, babies learn about cultural norms and interactional routines, or that shared actions are accompanied by shared feelings and intentions. But the empirical evidence to back up such theories is largely missing.
Read more at Science Daily
In the study, a researcher met 6-month old babies in their homes and played with them in four different ways. The researcher either: imitated everything the babies did as a mirror, or as a reverse mirror, imitated only the bodily actions of the babies while keeping an immobile face, or responded with a different action when the babies acted. The latter is called contingent responding and is how most parents would respond to their baby -- when the baby does or needs something, you react accordingly.
The researchers found that the babies looked and smiled longer, and tried to approach the adult more often, during the close mirroring of their actions.
"Imitating young infants seems to be an effective way to catch their interest and bond with them. The mothers were quite surprised to see their infants joyfully engaging in imitation games with a stranger, but also impressed by the infants' behaviours," says Gabriela-Alina Sauciuc, researcher at Lund University and main author of the study.
There was also much testing behavior during imitation. For example, if the baby hit the table and the researcher imitated that action, the baby would then hit the table several times, while carefully watching the researcher's responses. Even when the researcher did not show any emotions at all while imitating, the babies still seemed to recognize that they were being imitated -- and still responded with testing behavior.
"This was quite interesting. When someone actively tests the person who is imitating them, it is usually seen as an indication that the imitated individual is aware that there is a correspondence between their own behaviour and the behaviour of the other," Sauciuc says.
Scientists have long speculated that, through frequent exposure to being imitated, babies learn about cultural norms and interactional routines, or that shared actions are accompanied by shared feelings and intentions. But the empirical evidence to back up such theories is largely missing.
Read more at Science Daily
New approach to some mental disorders
Some of the most common mental disorders, including depression, anxiety and PTSD, might not be disorders at all, according to a recent paper by Washington State University biological anthropologists.
In the paper, published in the Yearbook of Physical Anthropology, the researchers propose a new approach to mental illness that would be informed by human evolution, noting that modern psychology, and in particular its use of drugs like antidepressants, has largely failed to reduce the prevalence of mental disorders. (This paper was made available online on Nov. 28, 2019 ahead of final publication in the issue on April 28, 2020). For example, the global prevalence of major depressive disorder and anxiety disorders remained steady at 4.4% and 4% respectively from 1990 to 2010.
The authors also theorize that depression, anxiety and post-traumatic stress disorder may be primarily responses to adversity; therefore, only treating the "psychic pain" of these issues with drugs will not solve the underlying problem. Kristen Syme, the first author on the paper and recent WSU Ph.D. graduate, compared it to medicating someone for a broken bone without setting the bone itself.
"The pain is not the disease; the pain is the function that is telling you there is a problem," said Syme. "Depression, anxiety and PTSD often involve a threat or exposure to violence, which are predictable sources for these things that we call mental diseases. Instead, they look more like sociocultural phenomena, so the solution is not necessarily fixing a dysfunction in the person's brain but fixing dysfunctions in the social world."
Syme and co-author Edward Hagen advocate for biological anthropologists to enter the study of the "diseases of the mind," to help find effective solutions, particularly for some problems that may be social instead of mental.
"Mental health research is still very much stuck in a view that comes out of the 19th century, and revived in 1980, of classifying everything by symptoms in the hopes of revealing underlying patterns that would lead to solutions, but it really has not," said Hagen, a WSU professor of evolutionary anthropology and corresponding author on the paper. "Even though we're using new measurements, like genetics, biomarkers and imaging, these still haven't added up to the insights needed to really improve people's lives."
Among the more problematic issues, the researchers point to the "chemical imbalance" theory of depression, which has helped create a boom in antidepressant drugs meant to modulate certain chemicals in the brain called neurotransmitters. A large meta-analysis of antidepressant trials in 2018 found that antidepressants had almost the same effect as a placebo, and their widespread use has not delivered measurable results. For example, in Australia alone, antidepressant use increased 352% from 1990 to 2002, yet there has been no observed reduction in the prevalence of mood, anxiety or substance use disorders in any country.
Instead of addressing mental issues by their symptoms, Hagen and Syme propose approaching mental illness by their probable causes. They acknowledge that some psychiatric disorders like schizophrenia are likely genetic and often inherited and others like Alzheimer's appear connected with aging.
However, the anthropologists argue that some conditions might be a mismatch between modern and ancestral environments such as attention-deficit/hyperactivity disorder, also known as ADHD. Hagen pointed out that there is little in our evolutionary history that accounts for children sitting at desks quietly while watching a teacher do math equations at a board.
Other disorders such as depression, anxiety and PTSD are not hereditary, occur at any age and are often tied to threatening experiences. Hagen and Syme propose they may be responses to adversity and serve as signals, much like physical pain does, to make people aware of the need for help.
These conditions also disproportionately affect people in developing countries. For instance, 1 in 5 people in conflict-affected countries suffer from depression versus 1 in 14 in worldwide.
Read more at Science Daily
In the paper, published in the Yearbook of Physical Anthropology, the researchers propose a new approach to mental illness that would be informed by human evolution, noting that modern psychology, and in particular its use of drugs like antidepressants, has largely failed to reduce the prevalence of mental disorders. (This paper was made available online on Nov. 28, 2019 ahead of final publication in the issue on April 28, 2020). For example, the global prevalence of major depressive disorder and anxiety disorders remained steady at 4.4% and 4% respectively from 1990 to 2010.
The authors also theorize that depression, anxiety and post-traumatic stress disorder may be primarily responses to adversity; therefore, only treating the "psychic pain" of these issues with drugs will not solve the underlying problem. Kristen Syme, the first author on the paper and recent WSU Ph.D. graduate, compared it to medicating someone for a broken bone without setting the bone itself.
"The pain is not the disease; the pain is the function that is telling you there is a problem," said Syme. "Depression, anxiety and PTSD often involve a threat or exposure to violence, which are predictable sources for these things that we call mental diseases. Instead, they look more like sociocultural phenomena, so the solution is not necessarily fixing a dysfunction in the person's brain but fixing dysfunctions in the social world."
Syme and co-author Edward Hagen advocate for biological anthropologists to enter the study of the "diseases of the mind," to help find effective solutions, particularly for some problems that may be social instead of mental.
"Mental health research is still very much stuck in a view that comes out of the 19th century, and revived in 1980, of classifying everything by symptoms in the hopes of revealing underlying patterns that would lead to solutions, but it really has not," said Hagen, a WSU professor of evolutionary anthropology and corresponding author on the paper. "Even though we're using new measurements, like genetics, biomarkers and imaging, these still haven't added up to the insights needed to really improve people's lives."
Among the more problematic issues, the researchers point to the "chemical imbalance" theory of depression, which has helped create a boom in antidepressant drugs meant to modulate certain chemicals in the brain called neurotransmitters. A large meta-analysis of antidepressant trials in 2018 found that antidepressants had almost the same effect as a placebo, and their widespread use has not delivered measurable results. For example, in Australia alone, antidepressant use increased 352% from 1990 to 2002, yet there has been no observed reduction in the prevalence of mood, anxiety or substance use disorders in any country.
Instead of addressing mental issues by their symptoms, Hagen and Syme propose approaching mental illness by their probable causes. They acknowledge that some psychiatric disorders like schizophrenia are likely genetic and often inherited and others like Alzheimer's appear connected with aging.
However, the anthropologists argue that some conditions might be a mismatch between modern and ancestral environments such as attention-deficit/hyperactivity disorder, also known as ADHD. Hagen pointed out that there is little in our evolutionary history that accounts for children sitting at desks quietly while watching a teacher do math equations at a board.
Other disorders such as depression, anxiety and PTSD are not hereditary, occur at any age and are often tied to threatening experiences. Hagen and Syme propose they may be responses to adversity and serve as signals, much like physical pain does, to make people aware of the need for help.
These conditions also disproportionately affect people in developing countries. For instance, 1 in 5 people in conflict-affected countries suffer from depression versus 1 in 14 in worldwide.
Read more at Science Daily
Even natural products can be harmful for the unborn child
Plant products ingested by pregnant women through their diet are broken down by the intestinal microbiota into chemical substances, some of which can cross the placental barrier and reach the fetus. These foreign substances can harm the unborn child, even if they are of "natural origin." Researchers at the Department for BioMedical Research (DBMR) at the University of Bern and Inselspital, University Hospital Bern, therefore warn against underestimating the effects of such substances.
All mammals, including humans are colonized by billions of microbes. These mainly live in our intestines, but which can also be found in the respiratory tract, on the skin and in the urogenital tract. In the gastroenterology research group of the Department for BioMedical Reserarch (DBMR) at the University of Bern and at the University Hospital Bern, Inselspital, Stephanie Ganal-Vonarburg and Andrew Macpherson investigate the interaction of these benign intestinal microbes with the host organism. The positive influence of the intestinal flora on our immune system has been recognized for a long time. Interestingly, even the maternal intestinal microbiota already has an efect on the development of the child's immune system during pregnancy as well as immediately after birth. In a review article published in the journal Science, Stephanie Ganal-Vonarburg and Andrew Macpherson compiled the latest knowledge of the extent to which the maternal intestinal flora is involved in the development of the child's immune system. They also found evidence that the effects of plant-based substances that pregnant women ingest through diet have so far been underestimated in research and may pose a potential risk to the unborn.
The placenta only offers partial protection
Scientists have always assumed that the developing embryo and fetus grow in a completely sterile environment in the womb, i.e. in the absence of colonizing microbes, and that colonization with micorbes only takes place at the time of birth. "However, the fetus is not protected against microbial metabolites that originate from the maternal intestinal flora," says Ganal-Vonarburg. The placenta offers only partial protection and transfer of microbial substances leads to the maturation of the offspring innate immune system already during pregnancy. Previous studies by the group around Ganal-Vonarburg and Macpherson have shown this. "It is common for pregnant women to take medication with great caution and only after consulting their doctor, since many medications can cross the placenta and interfere with the child's development. However, much less is known about which naturally occurring substances present in the diet can pass on to the unborn child and to what extent this can be beneficial or harmful for the development of the child's immune system," explains Ganal-Vonarburg.
Even plant substances need to be handled with caution
Together with Andrew Macpherson, she has now summarized published research results and found evidence that metabolic products from the diet cannot only directly reach the the maternal organism and thus into the developing fetus, but that this often only occurs after metabolism through the intestinal flora. This also applies to the intake of herbal products, such as superfoods that are considered particularly healthy during pregnancy, such as goji berries or chia seeds: "Although plants products are 'natural' substances, they are always so-called xenobiotic substances that are foreign to the body and should be handled very carefully," says Macpherson. "Especially when pregnant women take plant-based products in large quantities."
Ganal-Vonarburg and Macpherson recommend that future studies should investigate which natural substances could have a beneficial or negative effect on the development of the unborn child and what influence differences in the maternal intestinal flora can have on this process.
Read more at Science Daily
All mammals, including humans are colonized by billions of microbes. These mainly live in our intestines, but which can also be found in the respiratory tract, on the skin and in the urogenital tract. In the gastroenterology research group of the Department for BioMedical Reserarch (DBMR) at the University of Bern and at the University Hospital Bern, Inselspital, Stephanie Ganal-Vonarburg and Andrew Macpherson investigate the interaction of these benign intestinal microbes with the host organism. The positive influence of the intestinal flora on our immune system has been recognized for a long time. Interestingly, even the maternal intestinal microbiota already has an efect on the development of the child's immune system during pregnancy as well as immediately after birth. In a review article published in the journal Science, Stephanie Ganal-Vonarburg and Andrew Macpherson compiled the latest knowledge of the extent to which the maternal intestinal flora is involved in the development of the child's immune system. They also found evidence that the effects of plant-based substances that pregnant women ingest through diet have so far been underestimated in research and may pose a potential risk to the unborn.
The placenta only offers partial protection
Scientists have always assumed that the developing embryo and fetus grow in a completely sterile environment in the womb, i.e. in the absence of colonizing microbes, and that colonization with micorbes only takes place at the time of birth. "However, the fetus is not protected against microbial metabolites that originate from the maternal intestinal flora," says Ganal-Vonarburg. The placenta offers only partial protection and transfer of microbial substances leads to the maturation of the offspring innate immune system already during pregnancy. Previous studies by the group around Ganal-Vonarburg and Macpherson have shown this. "It is common for pregnant women to take medication with great caution and only after consulting their doctor, since many medications can cross the placenta and interfere with the child's development. However, much less is known about which naturally occurring substances present in the diet can pass on to the unborn child and to what extent this can be beneficial or harmful for the development of the child's immune system," explains Ganal-Vonarburg.
Even plant substances need to be handled with caution
Together with Andrew Macpherson, she has now summarized published research results and found evidence that metabolic products from the diet cannot only directly reach the the maternal organism and thus into the developing fetus, but that this often only occurs after metabolism through the intestinal flora. This also applies to the intake of herbal products, such as superfoods that are considered particularly healthy during pregnancy, such as goji berries or chia seeds: "Although plants products are 'natural' substances, they are always so-called xenobiotic substances that are foreign to the body and should be handled very carefully," says Macpherson. "Especially when pregnant women take plant-based products in large quantities."
Ganal-Vonarburg and Macpherson recommend that future studies should investigate which natural substances could have a beneficial or negative effect on the development of the unborn child and what influence differences in the maternal intestinal flora can have on this process.
Read more at Science Daily
May 25, 2020
Migration patterns reveal an Eden for ancient humans and animals
Pinnacle Point, a series of archaeological sites that overlook a now submerged section of South Africa's coastline and one of the world's most important localities for the study of modern human origins, was as much of an Eden for animals as it was for early humans. Jamie Hodgkins, PhD, assistant professor of anthropology at University of Colorado Denver, and her team drilled ancient herbivore teeth to find that many local animals stayed put in the ecologically rich ecosystem, which may explain why humans flourished there, too.
Home to the Earliest Modern Humans
Home to some of the richest evidence for the behavior and culture of the earliest clearly modern humans, the submerged shelf called the Palaeo-Agulhas Plain (PAP) once formed its own ecosystem. Co-author Curtis Marean, PhD, Arizona State University, has worked with teams of scientists for decades to reconstruct the locale back into the Pleistocene, the time period that spanned from 2.6 million to 11,700 years ago.
In this study, the researchers looked specifically at antelope migratory patterns at Pinnacle Point. This series of cave sites that sit on the modern South African coast offers archaeological materials from humans who were living and hunting there back to 170,000 years ago.
"During glacial cycles, the coastal shelf was exposed," said Hodgkins. "There would have been a huge amount of land in front of the cave sites. We thought it was likely that humans and carnivores were hunting animals as they migrated east and west over the exposed shelve."
A Lack of Migratory Pattern
Hodgkins and her team wanted to understand those migratory patterns. They studied the carbon and oxygen isotopes within the tooth enamel of many large herbivores, including Redunca, or reedbuck, a nonmigratory antelope. Tooth enamel can reveal a pattern of migration by tracking changing levels of carbon from the plants an animal eats as its teeth grow.
In general, wetter, cooler environments are home to C3 plants; hotter, drier environments are home to C4 plants. Animals like lush vegetation, which means they tend to follow the rain patterns: in this case east for summer rain (C4 grasses), and west for winter rain (C3 grasses). If animals were migrating between summer and winter rainfall zones, their tooth enamel would register that annual C3 and C4 plant rotation as a sinusoidal curve as their teeth grew.
A) Map of South Africa (SA) showing the distribution of C4 grasses associated with the percentage of summer rain from east to west along the coast, and with the winter rainfall zone in the west (modified from Vogel, 1978); B) A map of SA showing the area of the Greater Cape Floristic Region with the expanded PAP and hypothesized animals migration (i.e. It is hypothesized that animals would have been undertaking long-distance migrations between the east coast in summer rainfall zone and west coast in the winter rainfall zone)
But when Hodgkins and her team used the nonmigratory reedbuck as their control animal, they found that the enamel from its typically migratory pals -- like the wildebeest, hartebeest, and springbok -- showed no discernible migratory pattern. Most animals seemed happy right where they were.
"They weren't struggling at Pinnacle Point," says Hodgkins. "We now know that powerful river systems supplied the expanded coast, thus animals didn't have to be migratory. It was a great location, resource-wise. During interglacials when the coast moved closer to the caves humans had shellfish and other marine resources, and when the coast expanded in glacial times hunters had access to a rich, terrestrial environment. Hunters wouldn't need to be as mobile with all of these herbivores wandering around."
Thriving in an Ecogeological Haven
Hodgkins' team's findings of this prehistoric Eden echoed another recent discovery. Seventy-four-thousand years ago, one of Earth's largest known eruptions at Mount Toba in Sumatra, Indonesia, created a global winter, causing population crashes. In 2018, researchers from Marean's group found that humans at Pinnacle Point not only survived, but thrived in the haven.
Hodgkins says this is just a first attempt at using isotopic data to test the hypothesis of east and west migration patterns at these sites and further research will be done.
"It is quite possible that animal migration patterns changed as the coastline moved in and out during glacial and interglacial cycles," said Hodgkins.
Read more at Science Dialy
Home to the Earliest Modern Humans
Home to some of the richest evidence for the behavior and culture of the earliest clearly modern humans, the submerged shelf called the Palaeo-Agulhas Plain (PAP) once formed its own ecosystem. Co-author Curtis Marean, PhD, Arizona State University, has worked with teams of scientists for decades to reconstruct the locale back into the Pleistocene, the time period that spanned from 2.6 million to 11,700 years ago.
In this study, the researchers looked specifically at antelope migratory patterns at Pinnacle Point. This series of cave sites that sit on the modern South African coast offers archaeological materials from humans who were living and hunting there back to 170,000 years ago.
"During glacial cycles, the coastal shelf was exposed," said Hodgkins. "There would have been a huge amount of land in front of the cave sites. We thought it was likely that humans and carnivores were hunting animals as they migrated east and west over the exposed shelve."
A Lack of Migratory Pattern
Hodgkins and her team wanted to understand those migratory patterns. They studied the carbon and oxygen isotopes within the tooth enamel of many large herbivores, including Redunca, or reedbuck, a nonmigratory antelope. Tooth enamel can reveal a pattern of migration by tracking changing levels of carbon from the plants an animal eats as its teeth grow.
In general, wetter, cooler environments are home to C3 plants; hotter, drier environments are home to C4 plants. Animals like lush vegetation, which means they tend to follow the rain patterns: in this case east for summer rain (C4 grasses), and west for winter rain (C3 grasses). If animals were migrating between summer and winter rainfall zones, their tooth enamel would register that annual C3 and C4 plant rotation as a sinusoidal curve as their teeth grew.
A) Map of South Africa (SA) showing the distribution of C4 grasses associated with the percentage of summer rain from east to west along the coast, and with the winter rainfall zone in the west (modified from Vogel, 1978); B) A map of SA showing the area of the Greater Cape Floristic Region with the expanded PAP and hypothesized animals migration (i.e. It is hypothesized that animals would have been undertaking long-distance migrations between the east coast in summer rainfall zone and west coast in the winter rainfall zone)
But when Hodgkins and her team used the nonmigratory reedbuck as their control animal, they found that the enamel from its typically migratory pals -- like the wildebeest, hartebeest, and springbok -- showed no discernible migratory pattern. Most animals seemed happy right where they were.
"They weren't struggling at Pinnacle Point," says Hodgkins. "We now know that powerful river systems supplied the expanded coast, thus animals didn't have to be migratory. It was a great location, resource-wise. During interglacials when the coast moved closer to the caves humans had shellfish and other marine resources, and when the coast expanded in glacial times hunters had access to a rich, terrestrial environment. Hunters wouldn't need to be as mobile with all of these herbivores wandering around."
Thriving in an Ecogeological Haven
Hodgkins' team's findings of this prehistoric Eden echoed another recent discovery. Seventy-four-thousand years ago, one of Earth's largest known eruptions at Mount Toba in Sumatra, Indonesia, created a global winter, causing population crashes. In 2018, researchers from Marean's group found that humans at Pinnacle Point not only survived, but thrived in the haven.
Hodgkins says this is just a first attempt at using isotopic data to test the hypothesis of east and west migration patterns at these sites and further research will be done.
"It is quite possible that animal migration patterns changed as the coastline moved in and out during glacial and interglacial cycles," said Hodgkins.
Read more at Science Dialy
How drones can monitor explosive volcanoes
Due to the difficult accessibility and the high risk of collapse or explosion, the imaging of active volcanoes has so far been a great challenge in volcanology. Researchers around Edgar Zorn from the German Research Centre for Geosciences GFZ in Potsdam are now presenting the results of a series of repeated survey flights with optical and thermal imaging cameras at the Santa Maria volcano in Guatemala. Drones were used to observe the lava dome, a viscous plug of lava. The researchers were able to show that the lava dome shows movements on two different time scales: slow expansion and growth of the dome and fast extrusion of viscous lava. The study was published in the journal "Scientific Reports."
"We have equipped a drone with different cameras," says Edgar Zorn from GFZ, the first author of the study. "We then flew the drone over the crater at various intervals, measuring the movements of lava flow and a lava dome using a specific type of stereo photography with a precision never seen before." By comparing the data from the drone, we were able to determine the flow velocity, movement patterns and surface temperature of the volcano. These parameters are important for predicting the danger of explosive volcanoes. The researchers also succeeded in deriving the flow properties of the lava from these data.
"We have shown that the use of drones can help to completely re-measure even the most dangerous and active volcanoes on Earth from a safe distance," continues Edgar Zorn. "A regular and systematic survey of dangerous volcanoes with drones seems to be almost within one's grasp," says Thomas Walter, volcanologist at GFZ, who was also involved in the study.
The two cameras of the drone used on the Caliente volcanic cone of the Santa Maria volcano were able to take high-resolution photos on the one hand and thermal imaging on the other. Using a special computer algorithm, the researchers were able to create complete and detailed 3D models from these images. They obtained a 3D topography and temperature model of the volcano with a resolution of only a few centimetres.
Drone missions considerably reduce the risk for volcanologists, as the cameras can be flown directly to the dangerous spots without the scientists having to go near them themselves. Instead, the greatest challenge lies in the post-processing and calculation of the models. "The 3D models of the various flights must be positioned exactly so that they can be compared. This requires painstaking detail work, but the effort is worth it because even minimal movements become immediately visible," says Edgar Zorn. "In the study, we presented some new possibilities for the representation and measurement of certain ground movements, which could be very useful in future projects."
From Science Daily
"We have equipped a drone with different cameras," says Edgar Zorn from GFZ, the first author of the study. "We then flew the drone over the crater at various intervals, measuring the movements of lava flow and a lava dome using a specific type of stereo photography with a precision never seen before." By comparing the data from the drone, we were able to determine the flow velocity, movement patterns and surface temperature of the volcano. These parameters are important for predicting the danger of explosive volcanoes. The researchers also succeeded in deriving the flow properties of the lava from these data.
"We have shown that the use of drones can help to completely re-measure even the most dangerous and active volcanoes on Earth from a safe distance," continues Edgar Zorn. "A regular and systematic survey of dangerous volcanoes with drones seems to be almost within one's grasp," says Thomas Walter, volcanologist at GFZ, who was also involved in the study.
The two cameras of the drone used on the Caliente volcanic cone of the Santa Maria volcano were able to take high-resolution photos on the one hand and thermal imaging on the other. Using a special computer algorithm, the researchers were able to create complete and detailed 3D models from these images. They obtained a 3D topography and temperature model of the volcano with a resolution of only a few centimetres.
Drone missions considerably reduce the risk for volcanologists, as the cameras can be flown directly to the dangerous spots without the scientists having to go near them themselves. Instead, the greatest challenge lies in the post-processing and calculation of the models. "The 3D models of the various flights must be positioned exactly so that they can be compared. This requires painstaking detail work, but the effort is worth it because even minimal movements become immediately visible," says Edgar Zorn. "In the study, we presented some new possibilities for the representation and measurement of certain ground movements, which could be very useful in future projects."
From Science Daily
Cosmic Ring of Fire' 11 Billion Years Ago: How did structures in early universe form?
Astronomers have captured an image of a super-rare type of galaxy -- described as a "cosmic ring of fire" -- as it existed 11 billion years ago.
The galaxy, which has roughly the mass of the Milky Way, is circular with a hole in the middle, rather like a titanic doughnut. Its discovery, announced in the journal Nature Astronomy, is set to shake up theories about the earliest formation of galactic structures and how they evolve.
"It is a very curious object that we've never seen before," said lead researcher Dr Tiantian Yuan, from Australia's ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D). "It looks strange and familiar at the same time."
The galaxy, named R5519, is 11 billion light-years from the Solar System. The hole at its centre is truly massive, with a diameter two billion times longer than the distance between the Earth and the Sun. To put it another way, it is three million times bigger than the diameter of the supermassive black hole in the galaxy Messier 87, which in 2019 became the first ever to be directly imaged.
"It is making stars at a rate 50 times greater than the Milky Way," said Dr Yuan, who is an ASTRO 3D Fellow based at the Centre for Astrophysics and Supercomputing at Swinburne University of Technology, in the state of Victoria.
"Most of that activity is taking place on its ring -- so it truly is a ring of fire."
Working with colleagues from around Australia, US, Canada, Belgium and Denmark, Dr Yuan used spectroscopic data gathered by the WM Keck Observatory in Hawaii and images recorded by NASA's Hubble Space Telescope to identify the unusual structure.
The evidence suggests it is a type known as a "collisional ring galaxy," making it the first one ever located in the early Universe.
There are two kinds of ring galaxies. The more common type forms because of internal processes. Collisional ones form -- as the name suggests -- as a result of immense and violent encounters with other galaxies.
In the nearby "local" Universe they are 1000 times rarer than the internally created type. Images of the much more distant R5519 stem from about 10.8 billion years ago, just three billion years after the Big Bang. They indicate that collisional ring galaxies have always been extremely uncommon.
ASTRO 3D co-author, Dr Ahmed Elagali, based at the International Centre for Radio Astronomy Research in Western Australia, said studying R5519 would help determine when spiral galaxies began to develop.
"Further, constraining the number density of ring galaxies through cosmic time can also be used to put constraints on the assembly and evolution of local-like galaxy groups," he added.
Another co-author, Professor Kenneth Freeman from the Australian National University, said the discovery had implications for understanding how galaxies like the Milky Way formed.
"The collisional formation of ring galaxies requires a thin disk to be present in the 'victim' galaxy before the collision occurs," he explained.
"The thin disk is the defining component of spiral galaxies: before it assembled, the galaxies were in a disorderly state, not yet recognisable as spiral galaxies."
"In the case of this ring galaxy, we are looking back into the early universe by 11 billion years, into a time when thin disks were only just assembling. For comparison, the thin disk of our Milky Way began to come together only about nine billion years ago. This discovery is an indication that disk assembly in spiral galaxies occurred over a more extended period than previously thought."
Read more at Science Daily
The galaxy, which has roughly the mass of the Milky Way, is circular with a hole in the middle, rather like a titanic doughnut. Its discovery, announced in the journal Nature Astronomy, is set to shake up theories about the earliest formation of galactic structures and how they evolve.
"It is a very curious object that we've never seen before," said lead researcher Dr Tiantian Yuan, from Australia's ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D). "It looks strange and familiar at the same time."
The galaxy, named R5519, is 11 billion light-years from the Solar System. The hole at its centre is truly massive, with a diameter two billion times longer than the distance between the Earth and the Sun. To put it another way, it is three million times bigger than the diameter of the supermassive black hole in the galaxy Messier 87, which in 2019 became the first ever to be directly imaged.
"It is making stars at a rate 50 times greater than the Milky Way," said Dr Yuan, who is an ASTRO 3D Fellow based at the Centre for Astrophysics and Supercomputing at Swinburne University of Technology, in the state of Victoria.
"Most of that activity is taking place on its ring -- so it truly is a ring of fire."
Working with colleagues from around Australia, US, Canada, Belgium and Denmark, Dr Yuan used spectroscopic data gathered by the WM Keck Observatory in Hawaii and images recorded by NASA's Hubble Space Telescope to identify the unusual structure.
The evidence suggests it is a type known as a "collisional ring galaxy," making it the first one ever located in the early Universe.
There are two kinds of ring galaxies. The more common type forms because of internal processes. Collisional ones form -- as the name suggests -- as a result of immense and violent encounters with other galaxies.
In the nearby "local" Universe they are 1000 times rarer than the internally created type. Images of the much more distant R5519 stem from about 10.8 billion years ago, just three billion years after the Big Bang. They indicate that collisional ring galaxies have always been extremely uncommon.
ASTRO 3D co-author, Dr Ahmed Elagali, based at the International Centre for Radio Astronomy Research in Western Australia, said studying R5519 would help determine when spiral galaxies began to develop.
"Further, constraining the number density of ring galaxies through cosmic time can also be used to put constraints on the assembly and evolution of local-like galaxy groups," he added.
Another co-author, Professor Kenneth Freeman from the Australian National University, said the discovery had implications for understanding how galaxies like the Milky Way formed.
"The collisional formation of ring galaxies requires a thin disk to be present in the 'victim' galaxy before the collision occurs," he explained.
"The thin disk is the defining component of spiral galaxies: before it assembled, the galaxies were in a disorderly state, not yet recognisable as spiral galaxies."
"In the case of this ring galaxy, we are looking back into the early universe by 11 billion years, into a time when thin disks were only just assembling. For comparison, the thin disk of our Milky Way began to come together only about nine billion years ago. This discovery is an indication that disk assembly in spiral galaxies occurred over a more extended period than previously thought."
Read more at Science Daily
Study reveals first evidence inherited genetics can drive cancer's spread
Sometimes cancer stays put, but often it metastasizes, spreading to new locations in the body. It has long been suspected that genetic mutations arising inside tumor cells drive this potentially devastating turn of events.
Now researchers have shown for the first time that our own pre-existing genetics can promote metastasis.
A new study, published May 25 in Nature Medicine, suggests that differences in a single gene, carried within someone's genome from birth, can alter progression of melanoma, a type of skin cancer. The researchers suspect these inherited variations may have the same effect on other types of cancer as well.
"Patients often ask 'Why am I so unlucky? Why did my cancer spread?' As doctors, we never had an answer," says lead investigator Sohail Tavazoie, Leon Hess Professor and senior attending physician. "This research provides an explanation."
The discovery may transform how scientists think about cancer metastasis, and lead to a better understanding patients' risks in order to inform treatment decisions, Tavazoie says.
The mystery of metastasis
Metastasis occurs when cancer cells escape the original tissue to establish new tumors elsewhere, a phenomenon that leads to the majority of cancer deaths. Scientists have suspected that cancer cells, which initially emerge due to mutations inside normal cells, gain their travelling ability following further mutations. But after decades of searching, they have yet to find such a genetic change that could be proven to encourage metastasis.
Previous research in Tavazoie's lab had identified a gene called APOE, present in the DNA of all of the body's cells before any cancer arises, that can impact the spread of melanoma. The gene produces a protein that appears to interfere with a number of processes used by cancer cells to metastasize, such as forming blood vessels, growing deeper into healthy tissue, and withstanding assault from tumor-fighting immune cells.
Humans, however, carry one of three different versions of ApoE: ApoE2, ApoE3, and ApoE4. Benjamin Ostendorf, a physician scientist in the lab, hypothesized that these variants could explain why melanoma progresses differently in different people.
In experiments with mice possessing one of each of the versions of the gene, he and colleagues found tumors in those with ApoE4 grew the smallest and spread the least.
A closer look revealed that ApoE4 is the most effective version of ApoE in terms of enhancing the immune response to tumor cells. Compared to animals with other variants, the mice carrying ApoE4 showed a greater abundance of tumor-fighting T cells recruited into the melanoma tumor, as well as reduced blood vessels.
"We think that a major impact of the variations in ApoE arises from differences in how they modulate the immune system's attack," Ostendorf says.
Toward better treatment
Genetic data from more than 300 human melanoma patients echoed the mouse experiments: On average, people with ApoE4 survived the longest, while those with ApoE2 lived the shortest. This connection to outcomes suggests that doctors could look at patients' genetics to assess the risk of their cancer progressing.
It could also influence the course of treatment. Melanoma patients are sometimes given therapy that encourages their own immune systems to better fight the cancer. The team's analysis of information from such patients, as well as experiments with mice, showed that those with ApoE4 respond best to immune-boosting therapies.
Likewise, the researchers showed that an experimental compound that increases production of ApoE, RGX-104, was effective at helping mice with ApoE4 fight off tumors. RGX-104 is currently in clinical trials. (Tavazoie is a scientific cofounder of Rgenix, the company that developed RGX-104.)
Further research is needed to determine how to optimize treatments for patients with other ApoE variants, Tavazoie says. ApoE2, for instance, was associated with an increased risk of metastasis. The researchers evidence so far suggests that ApoE3's metastasis-suppressing ability falls between that of the other two. "We need to find those patients whose genetics put them at risk for poor survival and determine what therapies work best for them," Tavazoie says.
The implications may extend beyond cancer. Other studies have shown that variations in ApoE contribute to Alzheimer's disease: ApoE4 aggravates risk of this neurodegenerative disorder, in contrast to its suppression of cancer progression.
Read more at Science Daily
Now researchers have shown for the first time that our own pre-existing genetics can promote metastasis.
A new study, published May 25 in Nature Medicine, suggests that differences in a single gene, carried within someone's genome from birth, can alter progression of melanoma, a type of skin cancer. The researchers suspect these inherited variations may have the same effect on other types of cancer as well.
"Patients often ask 'Why am I so unlucky? Why did my cancer spread?' As doctors, we never had an answer," says lead investigator Sohail Tavazoie, Leon Hess Professor and senior attending physician. "This research provides an explanation."
The discovery may transform how scientists think about cancer metastasis, and lead to a better understanding patients' risks in order to inform treatment decisions, Tavazoie says.
The mystery of metastasis
Metastasis occurs when cancer cells escape the original tissue to establish new tumors elsewhere, a phenomenon that leads to the majority of cancer deaths. Scientists have suspected that cancer cells, which initially emerge due to mutations inside normal cells, gain their travelling ability following further mutations. But after decades of searching, they have yet to find such a genetic change that could be proven to encourage metastasis.
Previous research in Tavazoie's lab had identified a gene called APOE, present in the DNA of all of the body's cells before any cancer arises, that can impact the spread of melanoma. The gene produces a protein that appears to interfere with a number of processes used by cancer cells to metastasize, such as forming blood vessels, growing deeper into healthy tissue, and withstanding assault from tumor-fighting immune cells.
Humans, however, carry one of three different versions of ApoE: ApoE2, ApoE3, and ApoE4. Benjamin Ostendorf, a physician scientist in the lab, hypothesized that these variants could explain why melanoma progresses differently in different people.
In experiments with mice possessing one of each of the versions of the gene, he and colleagues found tumors in those with ApoE4 grew the smallest and spread the least.
A closer look revealed that ApoE4 is the most effective version of ApoE in terms of enhancing the immune response to tumor cells. Compared to animals with other variants, the mice carrying ApoE4 showed a greater abundance of tumor-fighting T cells recruited into the melanoma tumor, as well as reduced blood vessels.
"We think that a major impact of the variations in ApoE arises from differences in how they modulate the immune system's attack," Ostendorf says.
Toward better treatment
Genetic data from more than 300 human melanoma patients echoed the mouse experiments: On average, people with ApoE4 survived the longest, while those with ApoE2 lived the shortest. This connection to outcomes suggests that doctors could look at patients' genetics to assess the risk of their cancer progressing.
It could also influence the course of treatment. Melanoma patients are sometimes given therapy that encourages their own immune systems to better fight the cancer. The team's analysis of information from such patients, as well as experiments with mice, showed that those with ApoE4 respond best to immune-boosting therapies.
Likewise, the researchers showed that an experimental compound that increases production of ApoE, RGX-104, was effective at helping mice with ApoE4 fight off tumors. RGX-104 is currently in clinical trials. (Tavazoie is a scientific cofounder of Rgenix, the company that developed RGX-104.)
Further research is needed to determine how to optimize treatments for patients with other ApoE variants, Tavazoie says. ApoE2, for instance, was associated with an increased risk of metastasis. The researchers evidence so far suggests that ApoE3's metastasis-suppressing ability falls between that of the other two. "We need to find those patients whose genetics put them at risk for poor survival and determine what therapies work best for them," Tavazoie says.
The implications may extend beyond cancer. Other studies have shown that variations in ApoE contribute to Alzheimer's disease: ApoE4 aggravates risk of this neurodegenerative disorder, in contrast to its suppression of cancer progression.
Read more at Science Daily
May 24, 2020
Brain's 'updating mechanisms' may create false memories
Senior author Professor Bryce Vissel, from the UTS Centre for Neuroscience & Regenerative Medicine, said his team used novel behavioural, molecular and computational techniques to investigate memories that have not been well-formed, and how the brain deals with them.
He explained, "For memories to be useful, they have to have been well-formed during an event -- that is, they have to accurately reflect what actually happened.
"However, in the real world many memories are likely to be inaccurate -- especially in situations where the experience was brief, sudden or highly emotional, as can often occur during trauma. Inaccurate memories can also occur when the memory is poorly encoded, potentially as a result of subtle differences in how each person processes memory or because of disease like Alzheimer's or dementia."
Lead author Dr Raphael Zinn said, "Our findings are exciting because they show that memory updating mechanisms that become activated after recall can refine and improve memories.
"Surprisingly, we found that the same process can, in some circumstances, lead to incorrect updating of the memory. We also identify one molecular mechanism, called reconsolidation, which could be mediating this process.
"This suggests we might be able to target such updating mechanisms therapeutically to treat memory and anxiety disorders where memory formation is poor."
The 6-year study shows that the same mechanism that updates poor memories can also severely distort them if it occurs in the wrong situation.
Professor Vissel said these findings could be useful for understanding memory fallibility in everyday life; fear and memory disorders, post-traumatic stress disorder (PTSD); and situations where accurate recall is critical, like witness testimony in courtrooms.
"While these findings come from studies in mice, this research is likely to apply across many animals with developed brains, including other mammals and humans. They might also tie in with dementias, where the main memory-related problem is an apparent inability to form accurate new memories.
"Why is memory fallible? Our study suggests that when an individual forms a poor memory, the brain reactivates the memory in a similar situation and then updates it. Sometimes a poorly formed memory can be wrongly reactivated in a similar, but irrelevant, situation. The brain may then update the memory from that irrelevant situation, causing the memory to become incorrect -- rather than creating a new and entirely different memory of the new situation."
Read more at Science Daily
He explained, "For memories to be useful, they have to have been well-formed during an event -- that is, they have to accurately reflect what actually happened.
"However, in the real world many memories are likely to be inaccurate -- especially in situations where the experience was brief, sudden or highly emotional, as can often occur during trauma. Inaccurate memories can also occur when the memory is poorly encoded, potentially as a result of subtle differences in how each person processes memory or because of disease like Alzheimer's or dementia."
Lead author Dr Raphael Zinn said, "Our findings are exciting because they show that memory updating mechanisms that become activated after recall can refine and improve memories.
"Surprisingly, we found that the same process can, in some circumstances, lead to incorrect updating of the memory. We also identify one molecular mechanism, called reconsolidation, which could be mediating this process.
"This suggests we might be able to target such updating mechanisms therapeutically to treat memory and anxiety disorders where memory formation is poor."
The 6-year study shows that the same mechanism that updates poor memories can also severely distort them if it occurs in the wrong situation.
Professor Vissel said these findings could be useful for understanding memory fallibility in everyday life; fear and memory disorders, post-traumatic stress disorder (PTSD); and situations where accurate recall is critical, like witness testimony in courtrooms.
"While these findings come from studies in mice, this research is likely to apply across many animals with developed brains, including other mammals and humans. They might also tie in with dementias, where the main memory-related problem is an apparent inability to form accurate new memories.
"Why is memory fallible? Our study suggests that when an individual forms a poor memory, the brain reactivates the memory in a similar situation and then updates it. Sometimes a poorly formed memory can be wrongly reactivated in a similar, but irrelevant, situation. The brain may then update the memory from that irrelevant situation, causing the memory to become incorrect -- rather than creating a new and entirely different memory of the new situation."
Read more at Science Daily
High blood pressure during and after exercise may be markers for disease later in life
Higher blood pressure during exercise and delayed blood pressure recovery after exercise are associated with a higher risk of hypertension, preclinical and clinical cardiovascular disease and death among middle-aged to older adults. Blood pressure responses to exercise are significant markers of cardiovascular disease and mortality risk in young to middle-aged adults. However, few studies have examined the associations of midlife blood pressure responses to submaximal (less than the maximum of which an individual is capable) exercise with the risk of cardiovascular outcomes and mortality in later life.
Researchers from Boston University School of Medicine (BUSM) evaluated the association of blood pressure changes and recovery with indicators of preclinical disease among participants from the Framingham Heart Study (average age 58 years, 53 percent women). They then followed these participants to assess whether these blood pressure changes were associated with the risk of developing hypertension, cardiovascular disease or dying.
They observed that both higher exercise systolic blood pressure (SBP) and exercise diastolic blood pressure (DBP) were associated with a greater risk of developing hypertension. Additionally, both delayed SBP and DBP recovery after exercise were associated with higher risk of cardiovascular disease and death.
"The way our blood pressure changes during and after exercise provides important information on whether we will develop disease in the future; this may help investigators evaluate whether this information can be used to better identify people who are at higher risk of developing hypertension and CVD, or dying later in life," explained corresponding author Vanessa Xanthakis, PhD, assistant professor of medicine and biostatistics at BUSM and an Investigator for the Framingham Heart Study.
Xanthakis recommends that people know their blood pressure numbers, speak to their physician regarding changes during and after exercise and follow a healthy lifestyle (including a regular physical activity schedule) to help lower risk of disease later in life.
Read more at Science Daily
Researchers from Boston University School of Medicine (BUSM) evaluated the association of blood pressure changes and recovery with indicators of preclinical disease among participants from the Framingham Heart Study (average age 58 years, 53 percent women). They then followed these participants to assess whether these blood pressure changes were associated with the risk of developing hypertension, cardiovascular disease or dying.
They observed that both higher exercise systolic blood pressure (SBP) and exercise diastolic blood pressure (DBP) were associated with a greater risk of developing hypertension. Additionally, both delayed SBP and DBP recovery after exercise were associated with higher risk of cardiovascular disease and death.
"The way our blood pressure changes during and after exercise provides important information on whether we will develop disease in the future; this may help investigators evaluate whether this information can be used to better identify people who are at higher risk of developing hypertension and CVD, or dying later in life," explained corresponding author Vanessa Xanthakis, PhD, assistant professor of medicine and biostatistics at BUSM and an Investigator for the Framingham Heart Study.
Xanthakis recommends that people know their blood pressure numbers, speak to their physician regarding changes during and after exercise and follow a healthy lifestyle (including a regular physical activity schedule) to help lower risk of disease later in life.
Read more at Science Daily
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