Matabele ants: Travelling faster with detours

These are Matabele ants carrying a termite prey back to the nest.

Termites are the African Matabele ants' (Megaponera analis) favourite dish. Proceeding in long files of 200 to 600, they raid termites at their foraging sites and haul the prey back to their nest where they are ultimately eaten.

Before starting their raids, the ants send out scouts to look for the termites' foraging sites. Once they have spotted them, the scout ants return to the nest to mobilize their comrades. On their way back to the nest, the scouts show astonishing navigational abilities: They take the quickest route rather than the shortest.

Travelling faster in open country

If the direct way back passes through an area densely grown with grass, for example, the scouts prefer taking detours through open terrain which enables them to double their pace -- and this is worth it: They travel much faster although they are not taking the shortest route. This reduces their time back to the nest by 35 percent on average as Erik T. Frank, Philipp Hönle, and Karl Eduard Linsenmair from Julius-Maximilians-Universität Würzburg (JMU) in Bavaria, Germany, discovered. The biologists' results have been published in the Journal of Experimental Biology.

Individual ants make decisions

"Other ant species are known to rely on various navigational aids to determine the shortest way back to the nest from a foraging site," Erik Franks says. The navigational skills of the Matabele ants seem to be even more complex, a finding the researchers want to explore in greater detail now.

Moreover, the JMU scientists were surprised that the decision which way to take is made by individual ants and not collectively. "We have thus provided the first proof of time optimized path integration by individuals in the ant kingdom," says Frank who is currently conducting postdoc research at the University of Lausanne.

From Science Daily

Can a quantum drum vibrate and stand still at the same time?

Researchers have studied how a 'drumstick' made of light could make a microscopic 'drum' vibrate and stand still at the same time.

A team of researchers from the UK and Australia have made a key step towards understanding the boundary between the quantum world and our everyday classical world.

Quantum mechanics is truly weird. Objects can behave like both particles and waves, and can be both here and there at the same time, defying our common sense. Such counterintuitive behaviour is typically confined to the microscopic realm and the question "why don't we see such behaviour in everyday objects?" challenges many scientists today.

Now, a team of researchers have developed a new technique to generate this type of quantum behaviour in the motion of a tiny drum just visible to the naked eye. The details of their research are published today in New Journal of Physics.

Project principal investigator, Dr Michael Vanner from the Quantum Measurement Lab at Imperial College London, said: "Such systems offer significant potential for the development of powerful new quantum-enhanced technologies, such as ultra-precise sensors, and new types of transducers.

"Excitingly, this research direction will also enable us to test the fundamental limits of quantum mechanics by observing how quantum superpositions behave at a large scale."

Mechanical vibrations, such as those that create the sound from a drum, are an important part of our everyday experience. Hitting a drum with a drumstick causes it to rapidly move up and down, producing the sound we hear.

In the quantum world, a drum can vibrate and stand still at the same time. However, generating such quantum motion is very challenging. lead author of the project Dr Martin Ringbauer from the University of Queensland node of the Australian Research Council Centre for Engineered Quantum Systems, said: "You need a special kind of drumstick to make such a quantum vibration with our tiny drum."

In recent years, the emerging field of quantum optomechanics has made great progress towards the goal of a quantum drum using laser light as a type of drumstick. However, many challenges remain, so the authors' present study takes an unconventional approach.

Dr Ringbauer continues: "We adapted a trick from optical quantum computing to help us play the quantum drum. We used a measurement with single particles of light -- photons -- to tailor the properties of the drumstick.

"This provides a promising route to making a mechanical version of Schrodinger's cat, where the drum vibrates and stands still at the same time."

These experiments have made the first observation of mechanical interferences fringes, which is a crucial step forward for the field.

In the experiment, the fringes were at a classical level due to thermal noise, but motivated by this success, the team are now working hard to improve their technique and operate the experiments at temperatures close to absolute zero where quantum mechanics is expected to dominate.

Read more at Science Daily

Limiting warming to 1.5 degree C would save majority of global species from climate change

Can we keep global warming to 1.5 degrees Celsius?

Limiting global warming to 1.5oC would save the vast majority of the world's plant and animal species from climate change -- according to new research led by the University of East Anglia.

A new report published today in Science reveals that limiting warming to the ultimate goal of the Paris Agreement would avoid half the risks assoCiated with warming of 2oC for plants and animals, and two thirds of the risks for insects.

Species across the globe would benefit -- but particularly those in Southern Africa, the Amazon, Europe and Australia.

Reducing the risk to insects is particularly important, the team say, because they are so vital for 'ecosystem services' such as pollinating crops and flowers, and being part of the food chain for other birds and animals.

Previous research focused on quantifying the benefits of limiting warming to 2oC above pre-industrial times -- the upper limit for temperature as set out in the Paris Agreement -- and did not look at insects.

This is the first study to explore how limiting warming to 1.5oC would benefit species globally.

Researchers at UEA and James Cook University in Australia studied some 115,000 species including 31,000 insects, 8,000 birds, 1,700 mammals, 1,800 reptiles, 1,000 amphibians and 71,000 plants in this, the largest scale study of its kind.

Lead researcher Prof Rachel Warren, from the Tyndall Centre for Climate Change Research at UEA, said: "We wanted to see how different projected climate futures caused areas to become climatically unsuitable for the species living there.

"We measured the risks to biodiversity by counting the number of species projected to lose more than half their geographic range due to climate change.

"We found that achieving the ultimate goal of the Paris Agreement, to limit warming to 1.5oC above pre-industrial levels, would reap enormous benefits for biodiversity -- much more so than limiting warming to 2oC.

"Insects are particularly sensitive to climate change. At 2oC warming, 18 per cent of the 31,000 insects we studied are projected to lose more than half their range.

"This is reduced to 6 per cent at 1.5oC. But even at 1.5oC, some species lose larger proportions of their range.

"The current global warming trajectory, if countries meet their international pledges to reduce CO2, is around 3oC. In this case, almost 50 per cent of insects would lose half their range.

"This is really important because insects are vital to ecosystems and for humans. They pollinate crops and flowers, they provide food for higher-level organisms, they break down detritus, they maintain a balance in ecosystems by eating the leaves of plants, and they help recycle nutrients in the soil.

"We found that the three major groups of insects responsible for pollination are particularly sensitive to warming.

"If temperatures rise by 3oC, ecosystem services provided by insects would be greatly reduced. Other research has already shown that insects are already in decline for other reasons, and this research shows that climate change would really compound the problem."

The study includes the ability of species to reloCate to more suitable loCations as the world warms. Birds, mammals and butterflies have the greatest ability to disperse. The dispersal means that a small number of species can gain in range by 2100.

Prof Warren added: "If warming is limited to 1.5oC by 2100 then more species can keep up or even gain in range, whereas if warming reached 2oC by 2100 many species cannot keep up and far more species lose large parts of their range."

Co-author Dr Jeff Price, also from UEA, added: "Examples of animals to really benefit from limiting warming to 1.5 include the critically endangered Black RhinoCeros, which is already highly threatened by poaching and habitat loss.

Read more at Science Daily

New genes found that determine how the heart responds to exercise

A new study by researchers at Queen Mary University of London and University College London (UCL) has discovered 30 new gene locations that determine how the heart responds to and recovers from exercise.

The study, published in the journal Nature Communications, was conducted using the genetic and electrocardiogram data of 67,000 people from UK Biobank.

The findings could be used to improve the identification of people with impaired heart rate during recovery and those at higher risk of heart disease mortality.

The difference in heart rate response to exercise was as much as 3.15 beats per minute, depending on the genetic risk score of an individual, while the difference in heart rate response to recovery differed by as much as 10.4 beats per minute.

Lead researcher Patricia Munroe, Professor of Molecular Medicine at Queen Mary's William Harvey Research Institute said: "Our findings advance our knowledge on key pathways controlling heart rate response to exercise and recovery, information which may be valuable in the future for cardiovascular risk prediction."

Co-lead researcher Pier Lambiase, Professor of Cardiology at UCL said: "This first study by our "Electrogenomics" group is a wonderful example of the power of the collaboration between UCL Electrophysiology & QMUL Genomics, opening new avenues to dissect the mechanistic links between heart control and cardiovascular outcomes."

The results have implications to target new therapies to treat abnormal heart rhythms and potentially increase heart health.

From Science Daily

Giraffes surprise biologists yet again

This is a group of juvenile giraffes.

New research from the University of Bristol has highlighted how little we know about giraffe behaviour and ecology.

It is commonly accepted that group sizes of animals increase when there is a risk of predation, since larger group sizes reduce the risk of individuals being killed, and there are 'many eyes' to spot any potential predation risk.

Now, in the first study of its kind, Bristol PhD student Zoe Muller from the School of Biological Sciences has found that this is not true for giraffes, and that the size of giraffe groups is not influenced by the presence of predators.

Zoe Muller said: "This is surprising, and highlights how little we know about even the most basic aspects of giraffe behaviour."

This study investigates how the grouping behaviour of giraffes differed in response to numerous factors, such as predation risk, habitat type and the characteristics of individuals.

Habitat type had some effect on group size, but the main effect on group size was in the behaviour of adult females, who were found to be in smaller groups when they had calves.

This is contrary to another popular belief that female giraffes form large groups to communally care for their young -- this study, published this week in the Journal of Zoology presents the first evidence to show that actually, the opposite is true.

Giraffe populations have declined by 40 percent in the last 30 years, and there are now thought to be fewer than 98,000 individuals remaining in the wild.

In recognition of their drastic decline in the wild, they have recently been listed as "Vulnerable" on the International Union for Conservation in Nature's Red List of Threatened Species.

However, conservation review is ongoing due to current debate over their taxonomic status, since some subspecies may be even more at risk of extinction than is currently recognised.

Zoe Muller added: "This research adds another important piece to the puzzle of understanding how giraffes live in the wild.

"Giraffes are a threatened species, suffering ongoing decline across Africa, and this research highlights how they are actually an incredibly misunderstood species. We can only manage and conserve giraffe populations effectively if we properly understand their behaviour and ecology, which we are only just beginning to do.

"Despite their prominence, giraffes have been significantly understudied in comparison to other charismatic African mammals. "The common misconception is that giraffes are 'everywhere' in Africa, yet recent research efforts have highlighted the fragmented and rapidly declining nature of their populations.

"Their recent listing as 'Vulnerable' on the IUCN red list is a valuable step towards recognising their potential to become extinct, and more research is sorely needed to understand the threats and challenges they face in the wild."

Read more at Science Daily

Smarter brains run on sparsely connected neurons

Erhan Genc investigates how intelligence is reflected in brain structures.

The more intelligent a person, the fewer connections there are between the neurons in his cerebral cortex. This is the result of a study conducted by neuroscientists working with Dr Erhan Genç and Christoph Fraenz at Ruhr-Universität Bochum; the study was performed using a specific neuroimaging technique that provides insights into the wiring of the brain on a microstructural level.

Together with colleagues from the University of New Mexico in Albuquerque, Humboldt University of Berlin and the Lovelace Biomedical and Environmental Research Institute in Albuquerque, the team from the biopsychology research unit in Bochum published their report in the journal Nature Communications on May 15, 2018.

Intelligence is determined by the number of dendrites

The researchers analysed the brains of 259 men and women using neurite orientation dispersion and density imaging. This method enabled them to measure the amount of dendrites in the cerebral cortex, i.e. extensions of nerve cells that are used by the cells to communicate with each other. In addition, all participants completed an IQ test. Subsequently, the researchers associated the gathered data with each other and found out: the more intelligent a person, the fewer dendrites there are in their cerebral cortex.

Using an independent, publicly accessible database, which had been compiled for the Human Connectome Project, the team confirmed these results in a second sample of around 500 individuals.

Previously conflicting results are thus explained

The new findings provide an explanation of conflicting results gathered in intelligence research to date. For one, it had been previously ascertained that intelligent people tend to have larger brains. "The assumption has been that larger brains contain more neurons and, consequently, possess more computational power," says Erhan Genç. However, other studies had shown that -- despite their comparatively high number of neurons -- the brains of intelligent people demonstrated less neuronal activity during an IQ test than the brains of less intelligent individuals.

"Intelligent brains possess lean, yet efficient neuronal connections," concludes Erhan Genç. "Thus, they boast high mental performance at low neuronal activity."

From Science Daily

More than a living syringe: Mosquito saliva alone triggers unexpected immune response

Aedes aegypti mosquitoes after a blood meal.

Mosquito season is around the corner, bringing with it a higher risk of catching potentially serious diseases transmitted by their bite. Mosquitoes also may increase the severity of the diseases they transmit, and researchers think that mosquito saliva plays an active role in this process. A team of researchers at Baylor College of Medicine has taken a closer look at the effect of mosquito saliva alone and found that it can trigger an unexpected variety of immune responses in an animal model of the human immune system. These results offer an opportunity to develop effective strategies to prevent mosquito-based transmission of disease. The study appears in the journal PLOS Neglected Tropical Diseases.

"Billions of people worldwide are exposed to diseases transmitted by mosquitoes, and many of these conditions do not have effective treatments," said corresponding author Dr. Rebecca Rico-Hesse, professor of molecular virology and microbiology at Baylor College of Medicine. "One of the interests of my lab is to study the development of dengue fever, which is caused by the dengue virus transmitted by mosquito Aedes aegypti."

The World Health Organization has estimated that 100 million dengue virus infections and 22,000 deaths occur yearly worldwide, mostly among children. According to the Centers for Disease Control and Prevention, more than one-third of the world's population lives in areas at risk of infection, making the dengue virus a leading cause of illness and death in the tropics and subtropics.

"One of the main limitations for studying dengue fever is that the dengue virus only causes the disease in humans; no other animals can be used as models of the condition to develop preventive and therapeutic measures," Rico-Hesse said. "To overcome this challenge, we have been working with a mouse model of the human immune system."

These 'humanized mice' were developed by other research groups from mice naturally born without their own immune system. These severely immunodeficient mice received human stem cells that gave rise to many of the components of the human immune system, creating a living humanized animal model in which Rico-Hesse and her colleagues can study factors that may affect the development of dengue fever.

"In 2012, we demonstrated in these humanized mice that mosquito-bite delivery and needle-injection delivery of dengue virus led to significantly different disease developments," Rico-Hesse said. "Importantly, mosquito-bite delivery of the virus resulted in a more human-like disease than the one we observed after needle-injection delivery of the virus. When the mosquitoes delivered the virus, the mice had more of a rash, more fever and other characteristics that mimic the disease presentation in humans."

These observations support the idea that mosquitoes are not just acting like 'syringes,' merely injecting viruses into the animals they feed on. Their saliva seems to contribute significantly to the development of the disease, which has prompted Rico-Hesse and her colleagues to investigate what this role might be. They began by determining the effect of bites from virus-free mosquitoes on the human immune response of humanized mice.

An unexpected complex response

To test the effect of virus-free mosquito saliva on humanized mice, the researchers held a vial containing mosquitoes against a footpad of anesthetized humanized mice, allowing a total of four mosquitoes to feed on both footpads.

The researchers then took blood and a number of other tissue samples six hours, 24 hours and seven days after the mosquitoes bit the mice, and determined the levels of cytokines, molecules that modulate the immune response, as well as the number and activity of different types of immune cells. They compared these results with those obtained from humanized mice that had not been bitten by mosquitoes.

To make the above determinations, the researchers used highly-sensitive techniques -- flow cytometry for immune cell analysis and multiplex cytokine bead array analysis for cytokines -- that allowed them to dissect the immune responses in great detail. This approach produced surprising results.

"We found that mosquito-delivered saliva induced a varied and complex immune response we were not anticipating," said co-author Dr. Silke Paust, assistant professor of pediatrics at Baylor and Texas Children's Hospital. "For instance, both the immune cell responses and the cytokine levels were affected. We saw activation of T helper cells 1, which generally contribute to antiviral immunity, as well as activation of T helper cells 2, which have been linked to allergic responses."

At various time points, the levels and activities of other types of immune cells also increased as others decreased. Overall, the researchers found evidence that mosquito saliva alone can trigger long-lasting immune responses -- up to seven days post-bite -- in multiple tissue types, including blood, skin and bone marrow.

"The diversity of the immune response was most striking to me. This is surprising given that no actual infection with any type of infectious agent occurred," said Paust, who also is a member of the Dan L Duncan Comprehensive Cancer Center at Baylor College of Medicine. "These results are evidence that components in the mosquito saliva can modulate the immune response in humanized mice."

The researchers will continue this study by investigating which of the more than 100 proteins in mosquito saliva are mediating the effects on the immune system, or may help the virus become more infectious. Identifying these proteins could help design strategies to fight transmission of dengue fever, as well as other diseases caused by viruses also transmitted by Aedes aegypti, such as Zika virus, chikungunya virus and yellow fever virus.

Read more at Science Daily

Quarks feel the pressure in the proton

Nuclear physicists have found that the proton's building blocks, the quarks, are subjected to a pressure of 100 decillion Pascal (1035) near the center of a proton, which is about 10 times greater than the pressure in the heart of a neutron star.

Inside every proton in every atom in the universe is a pressure cooker environment that surpasses the atom-crushing heart of a neutron star. That's according to the first measurement of a mechanical property of subatomic particles, the pressure distribution inside the proton, which was carried out by scientists at the Department of Energy's Thomas Jefferson National Accelerator Facility.

The nuclear physicists found that the proton's building blocks, the quarks, are subjected to a pressure of 100 decillion Pascal (1035) near the center of a proton, which is about 10 times greater than the pressure in the heart of a neutron star. The result was recently published in the journal Nature.

"We found an extremely high outward-directed pressure from the center of the proton, and a much lower and more extended inward-directed pressure near the proton's periphery," explains Volker Burkert, Jefferson Lab Hall B Leader and a co-author on the paper.

Burkert says that the distribution of pressure inside the proton is dictated by the strong force, the force that binds three quarks together to make a proton.

"Our results also shed light on the distribution of the strong force inside the proton," he said. "We are providing a way of visualizing the magnitude and distribution of the strong force inside the proton. This opens up an entirely new direction in nuclear and particle physics that can be explored in the future."

Once thought impossible to obtain, this measurement is the result of a clever pairing of two theoretical frameworks with existing data.

First, there are the generalized parton distributions. GPDs allow researchers to produce a 3D image of the proton's structure as probed by the electromagnetic force. The second are the gravitational form factors of the proton. These form factors describe what the mechanical structure of the proton would be if researchers could probe the proton via the gravitational force.

The theorist who developed the concept of gravitational form factors in 1966, Heinz Pagels, famously observed in the paper detailing them that there was "very little hope of learning anything about the detailed mechanical structure of a particle, because of the extreme weakness of the gravitational interaction."

Recent theoretical work, however, has connected GPDs to the gravitational form factors, allowing the results from electromagnetic probes of protons to substitute for gravitational probes.

"This is the beauty of it. You have this map that you think you will never get," said Latifa Elouadrhiri, a Jefferson Lab staff scientist and co-author on the paper. "But here we are, filling it in with this electromagnetic probe."

The electromagnetic probe consists of beams of electrons produced by the Continuous Electron Beam Accelerator Facility, a DOE Office of Science User Facility. These electrons are directed into the nuclei of atoms, where they interact electromagnetically with the quarks inside protons via a process called deeply virtual Compton scattering.

In the DVCS process, an electron enters a proton and exchanges a virtual photon with a quark, transferring energy to the quark and proton. A short time later, the proton releases this energy by emitting another photon and continues on intact. This process is analogous to the calculations Pagels performed for how it would be possible to probe the proton gravitationally via a hypothetical beam of gravitons. The Jefferson Lab researchers were able to exploit a similarity between the well-known electromagnetic and hypothetical gravitational studies to get their result.

"There's a photon coming in and a photon coming out. And the pair of photons both are spin-1. That gives us the same information as exchanging one graviton particle with spin-2," says Francois-Xavier Girod, a Jefferson Lab staff scientist and co-author on the paper. "So now, one can basically do the same thing that we have done in electromagnetic processes -- but relative to the gravitational form factors, which represent the mechanical structure of the proton."

Read more at Science Daily

How the gut influences neurologic disease

Scientists examined gut microbes and the influence of changes in diet in mice.

A study published this week in Nature sheds new light on the connection between the gut and the brain, untangling the complex interplay that allows the byproducts of microorganisms living in the gut to influence the progression of neurodegenerative diseases. Investigators from Brigham and Women's Hospital (BWH) have been using both animal models and human cells from patients to tease out the key players involved in the gut-brain connection as well as in the crosstalk between immune cells and brain cells. Their new publication defines a pathway that may help guide therapies for multiple sclerosis and other neurologic diseases.

"These findings provide a clear understanding of how the gut impacts central nervous system resident cells in the brain," said corresponding author Francisco Quintana, PhD, of the Ann Romney Center for Neurologic Diseases at BWH. "Now that we have an idea of the players involved, we can begin to go after them to develop new therapies."

The new research focuses on the influence of gut microbes on two types of cells that play a major role in the central nervous system: microglia and astrocytes. Microglia are an integral part of the body's immune system, responsible for scavenging the CNS and getting rid of plaques, damaged cells and other materials that need to be cleared. But microglia can also secrete compounds that induce neurotoxic properties on the star-shaped brain cells known as astrocytes. This damage is thought to contribute to many neurologic diseases, including multiple sclerosis.

Brigham researchers have previously explored the gut-brain connection to gain insights into multiple sclerosis. Although some studies have examined how byproducts from organisms living in the gut may promote inflammation in the brain, the current study is the first to report on how microbial products may act directly on microglia to prevent inflammation. The team reports that the byproducts that microbes produce when they break down dietary tryptophan -- an amino acid found in turkey and other foods -- may limit inflammation in the brain through their influence on microglia.

To conduct their study, the research team examined gut microbes and the influence of changes in diet in a mouse model of multiple sclerosis. They found that compounds resulting from the breakdown of tryptophan can cross the blood-brain barrier, activating an anti-inflammatory pathway that limits neurodegeneration. The researchers also studied human multiple sclerosis brain samples, finding evidence of the same pathway and players.

Activation of this same pathway has recently been linked to Alzheimer's disease and glioblastoma. The Ann Romney Center for Neurologic Diseases, of which Quintana is a part, brings experts together to accelerate treatment for these diseases, as well as multiple sclerosis Parkinson's disease and ALS (Lou Gehrig's disease).

"It is likely the mechanisms we've uncovered are relevant for other neurologic diseases in addition to multiple sclerosis," said Quintana. "These insights could guide us toward new therapies for MS and other diseases."

Read more at Science Daily

Critically endangered South American forests were planted by ancient peoples

Campos da Serra y Floresta de Araucari.

Critically endangered South American forests thought to be the result of climate change were actually spread by ancient communities, archaeologists have found.

Huge swathes of land in Chile, Brazil and Argentina are covered with millions of Araucaria, or monkey puzzle trees, thanks to people planting or cultivating them more than a thousand years ago, a new study shows. Recent logging means the landscape is now one of the world's most at-risk environments.

It had been thought the forests expanded due to wetter and warmer weather. But the research shows the rapidly expanding pre-Columbian population of South America, Southern Jê communities, were really responsible.

New excavations and soil analysis shows the forests, still hugely culturally and economically important to people living in South America, expanded between 1,410 and 900 years ago because of population growth and cultural changes.

Dr Mark Robinson, from the University of Exeter, who led the British Academy and AHRC-FAPESP-funded research, said: "Our research shows these landscapes were human-made. Communities settled on grassland, and then -- perhaps because they modified the soil, protected seedlings or even planted trees -- established these forests in places where geographically they shouldn't have flourished."

The forests date back to the period when dinosaurs roamed. The iconic monkey puzzle tree, or Parana pine, has grown in the region for thousands of years. Its nuts were one of the most important food sources for ancient communities, attracted game for hunting when nuts were ripe. They were also a valuable source of timber, fuel and resin, and became an integral part of southern Jê cosmology. Communities still call themselves "people of the Araucaria," and hold festivals to celebrate the forests.

Of the 19 species of Araucaria tree, five are classified as endangered and two, including the Brazilian Araucaria angustifolia, are critically endangered. Reports from the late 1800s describe trees with diameters of over 2 m, reaching 42 m in height. Modern trees are only around 17.7 m tall.

The archaeological analysis began because the experts, from the University of Exeter, University of Reading, University of São Paulo, University of New Mexico, Universidade Federal de Pelotas and Universidade do Sul de Santa Catarina, noticed that in areas of low human activity forests are limited to south-facing slopes, whereas in areas of extensive archaeology, forests cover the entire landscape. They were able to analyse soil isotopes reflecting vegetation and archaeological evidence from Campo Belo do Sul, Santa Catarina State, Brazil, to test whether this pattern was directly related to past human activity.

The study shows the forests first expanded around 4,480 to 3,200 years ago, most likely near streams, and this may have been caused by a wetter climate. But a more rapid and extensive expansion across the whole region later happened between 1,410 and 900 years ago, when forests expanded into highland areas. The weather during this time was dry and less humid. This expansion of the forests coincides with population growth and increasingly complex and hierarchical societies in South America.

The expansion in forests reached a peak around 800 years ago. The number of people in South America declined 400 years ago when European settlers arrived in the area. The population did not begin to recover until the 19 century, when loggers began exploiting the Araucaria forests for timber.

Professor José Iriarte, from the University of Exeter, another member of the research team, said: "This study shows the Araucaria forests were expanded beyond their natural boundaries, they were used sustainably for hundreds of years, and conservation strategies must reflect this so they balance protection, heritage and economic development."

Read more at Science Daily

Major shift in marine life occurred 33 million years later in the South

A news study shows how sea-lilies were in the Southern Hemisphere until much more recently than previously thought.

A new study of marine fossils from Antarctica, Australia, New Zealand and South America reveals that one of the greatest changes to the evolution of life in our oceans occurred more recently in the Southern Hemisphere than previously thought. The results are published today (17 May 2018) in the journal Communications Biology.

The Marine Mesozoic Revolution (MMR) is a key theory in evolutionary history. While dinosaurs ruled the land, profound changes occurred in the shallow seas that covered the Earth.

During the Mesozoic, around 200 million years ago, marine predators evolved that could drill holes and crush the shells of their prey. And although small in comparison to dinosaurs, these new predators, including crustacea and some types of modern fish, had a dramatic impact on marine life.

Among the species most heavily affected were sea lilies or isocrinids -- invertebrates tethered to the seafloor by graceful stalks. Side on, these stalks resemble a vertebral column; in cross section, they are shaped like a five-pointed star -- because sea lilies are related to starfish, sea urchins, and sand dollars. At their height during the Paleozoic, forests of sea lilies carpeted seafloors the world over.

Their restricted ability to move made sea lilies vulnerable to the new predators, so during the MMR they were forced into deeper waters in order to survive. Because it marked such a radical change in marine communities, scientists have long sought to understand this shift. They believed it occurred around 66 million years ago, but this new study shows that in the Southern Hemisphere, sea lilies remained in shallow waters until much more recently -- around 33 million years ago.

A team from British Antarctic Survey, the University of Cambridge, the University of Western Australia, and the Royal Botanic Gardens, Victoria, made the discovery when they brought together field samples from Antarctica and Australia, with fossils from museum collections for the first time. The study provides conclusive evidence that this change happened at different times in different parts of the globe, and in the Antarctic and Australia, sea lilies hung on in shallow waters until the end of the Eocene, around 33 million years ago and it is unknown exactly why.

The study shows that knowing more about the Antarctic can reshape -- or overturn -- existing scientific theories.

According to lead author Dr Rowan Whittle from British Antarctic Survey: "It is surprising to see such a difference in what was happening at either end of the world. In the Northern Hemisphere these changes happened whilst the dinosaurs ruled the land, but by the time these sea lilies moved into the deep ocean in the Southern Hemisphere the dinosaurs had been extinct for over 30 million years.

"Given how the ocean is changing and projected to change in the future it is vital that we understand how different parts of the world could be affected in different ways and at a range of timescales."

To get this richer picture of how sea lilies responded to the changing oceans of the Southern Hemisphere over millions of years, the team travelled to some of the remotest regions of Western Australia and Antarctica. Their hunt for fossil sea lilies was rewarded by the discovery of nine new species.

Co-author Dr Aaron Hunter from the University of Cambridge says: "We have documented how these sea lilies evolved as Australia split away from Antarctica moving north and becoming the arid outback we know today, while ice formed over the South Polar Region.

Read more at Science Daily

Evidence for stars forming just 250 million years after Big Bang

This image shows the galaxy cluster MACS J1149.5+2223 taken with the NASA/ESA Hubble Space Telescope; the inset image is the very distant galaxy MACS1149-JD1, seen as it was 13.3 billion years ago and observed with ALMA. Here, the oxygen distribution detected with ALMA is depicted in red.

An international team of astronomers used ALMA to observe a distant galaxy called MACS1149-JD1. They detected a very faint glow emitted by ionised oxygen in the galaxy. As this infrared light travelled across space, the expansion of the Universe stretched it to wavelengths more than ten times longer by the time it reached Earth and was detected by ALMA. The team inferred that the signal was emitted 13.3 billion years ago (or 500 million years after the Big Bang), making it the most distant oxygen ever detected by any telescope. The presence of oxygen is a clear sign that there must have been even earlier generations of stars in this galaxy.

"I was thrilled to see the signal of the distant oxygen in the ALMA data," says Takuya Hashimoto, the lead author of the new paper and a researcher at both Osaka Sangyo University and the National Astronomical Observatory of Japan . "This detection pushes back the frontiers of the observable Universe."

In addition to the glow from oxygen picked up by ALMA, a weaker signal of hydrogen emission was also detected by ESO's Very Large Telescope (VLT). The distance to the galaxy determined from this observation is consistent with the distance from the oxygen observation. This makes MACS1149-JD1 the most distant galaxy with a precise distance measurement and the most distant galaxy ever observed with ALMA or the VLT.

"This galaxy is seen at a time when the Universe was only 500 million years old and yet it already has a population of mature stars," explains Nicolas Laporte, a researcher at University College London (UCL) in the UK and second author of the new paper. "We are therefore able to use this galaxy to probe into an earlier, completely uncharted period of cosmic history."

For a period after the Big Bang there was no oxygen in the Universe; it was created by the fusion processes of the first stars and then released when these stars died. The detection of oxygen in MACS1149-JD1 indicates that these earlier generations of stars had been already formed and expelled oxygen by just 500 million years after the beginning of the Universe.

But when did this earlier star formation occur? To find out, the team reconstructed the earlier history of MACS1149-JD1 using infrared data taken with the NASA/ESA Hubble Space Telescope and the NASA Spitzer Space Telescope. They found that the observed brightness of the galaxy is well-explained by a model where the onset of star formation corresponds to only 250 million years after the Universe began.

The maturity of the stars seen in MACS1149-JD1 raises the question of when the very first galaxies emerged from total darkness, an epoch astronomers romantically term "cosmic dawn." By establishing the age of MACS1149-JD1, the team has effectively demonstrated that galaxies existed earlier than those we can currently directly detect.

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New lineage of microbes living in Yellowstone sheds light on origin of life

Bill Inskeep, professor in the Department of Land Resources and Environmental Sciences at Montana State University, drives a scanning electron microscope in the Image and Chemical Analysis Laboratory on campus, Monday, May 14, 2018, in Bozeman, Mont. Inskeep has been published in the Nature Microbiology scientific journal for his research on Marsarchaeota, geothermal iron-oxide microbial mats found in Yellowstone National Park.

Montana State University scientists have found a new lineage of microbes living in Yellowstone National Park's thermal features that sheds light on the origin of life, the evolution of archaeal life and the importance of iron in early life.

Professor William Inskeep and his team of researchers published their findings May 14 in the scientific journal Nature Microbiology.

"The discovery of archaeal lineages is critical to our understanding of the universal tree of life and evolutionary history of the Earth," the group wrote. "Geochemically diverse thermal environments in Yellowstone National Park provide unprecedented opportunities for studying archaea in habitats that may represent analogues of early Earth."

Archaea is one of the three domains of life, the others being bacteria and eukaryotes. Like bacteria, archaea are single-cell organisms. The eukaryote domain contains more cellularly complex organisms, such as humans, other animals, plants and fungi.

The scientists called the new archaeal lineage Marsarchaeota after Mars, the red planet, because these organisms thrive in habitats containing iron oxides. Within Marsarchaeota, they discovered two main subgroups that live throughout Yellowstone and thrive in hot, acidic water where iron oxide is the main mineral. One subgroup lives in water above 122 degrees Fahrenheit, and the other lives in water above 140 to 176 degrees. The water is about as acidic as grapefruit juice. Their microbial mats are red because of the iron oxide.

"It's interesting that the habitat of these organisms contains (iron) minerals similar to those found on the surface of Mars," Inskeep said.

He added that microbes produce iron oxide, but the Marsarchaeota do not. They might be involved in reducing iron into a simpler form, "which is important from an early Earth standpoint. Iron cycling has been implicated as being extremely important in early Earth conditions."

The Marsarchaeota live fairly deep in microbial mats, but they still require low levels of oxygen, Inskeep said. The subgroups are so abundant that, together, they can account for as much as half of the organisms living within a single microbial mat.

The scientists studied microbial mats throughout Yellowstone. Microorganisms in these "microbial beaver dams" produce iron oxide that creates terraces, which, in turn, block streams. As water (only a couple of millimeters deep) runs over the terraces, oxygen is captured from the atmosphere and supplied to the Marsarchaeota.

"Physics comes together with chemistry and microbiology," Inskeep said. "It's like a sweet spot of conditions that this group of organisms likes."

In addition to learning more about life on early Earth and the potential for life on Mars, Inskeep said the research can help scientists understand more about high-temperature biology.

"Knowing about this new group of archaea provides additional pieces of the puzzle for understanding high-temperature biology," he said. "That could be important in industry and molecular biology."

The work that resulted in the Nature Microbiology paper was the culmination of research that took place over the past decade, said Inskeep, who has studied the geochemistry and microbiology of Yellowstone's high-temperature environments for the last 20 years. Inskeep is a professor of geomicrobiology in MSU's Department of Land Resources and Environmental Sciences in the College of Agriculture and co-founder of MSU's Thermal Biology Institute.

The lead authors of the Nature Microbiology paper earned their doctorates at MSU and were part of NSF's Integrative Graduate Education and Research Traineeship (IGERT) program while at MSU. Zackary Jay is now a postdoctoral researcher in the Department of Chemical and Biological Engineering in the Norm Asbjornson College of Engineering and the Center for Biofilm Engineering at MSU. Jacob Beam is now a postdoctoral researcher at Bigelow Laboratory for Ocean Sciences at East Boothbay, Maine.

"In the end, after many years of work, it's exciting, and a relief, to have our team's work recognized and published, particularly in a high impact journal," Jay said.

Other co-authors were Mensur Dlakic from MSU's Department of Microbiology and Immunology in the College of Letters and Science and College of Agriculture; Douglas Rusch from the Center for Bioinformatics at Indiana University; and Mark Kozubal from the Thermal Biology Institute, MSU's Department of Land Resources and Environmental Sciences, and Sustainable Bioproducts in Bozeman.

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Astronomers find fastest-growing black hole known in space

Computer-simulated image of a supermassive black hole.

Astronomers at ANU have found the fastest-growing black hole known in the Universe, describing it as a monster that devours a mass equivalent to our sun every two days.

The astronomers have looked back more than 12 billion years to the early dark ages of the Universe, when this supermassive black hole was estimated to be the size of about 20 billion suns with a one per cent growth rate every one million years.

"This black hole is growing so rapidly that it's shining thousands of times more brightly than an entire galaxy, due to all of the gases it sucks in daily that cause lots of friction and heat," said Dr Wolf from the ANU Research School of Astronomy and Astrophysics.

"If we had this monster sitting at the centre of our Milky Way galaxy, it would appear 10 times brighter than a full moon. It would appear as an incredibly bright pin-point star that would almost wash out all of the stars in the sky."

Dr Wolf said the energy emitted from this newly discovered supermassive black hole, also known as a quasar, was mostly ultraviolet light but also radiated x-rays.

"Again, if this monster was at the centre of the Milky Way it would likely make life on Earth impossible with the huge amounts of x-rays emanating from it," he said.

The SkyMapper telescope at the ANU Siding Spring Observatory detected this light in the near-infrared, as the light waves had red-shifted over the billions of light years to Earth.

"As the Universe expands, space expands and that stretches the light waves and changes their colour," Dr Wolf said.

"These large and rapidly-growing blackholes are exceedingly rare, and we have been searching for them with SkyMapper for several months now. The European Space Agency's Gaia satellite, which measures tiny motions of celestial objects, helped us find this supermassive black hole."

Dr Wolf said the Gaia satellite confirmed the object that they had found was sitting still, meaning that it was far away and it was a candidate to be a very large quasar.

The discovery of the new supermassive black hole was confirmed using the spectrograph on the ANU 2.3 metre telescope to split colours into spectral lines.

"We don't know how this one grew so large, so quickly in the early days of the Universe," Dr Wolf said.

"The hunt is on to find even faster-growing black holes."

Dr Wolf said as these kinds of black holes shine, they can be used as beacons to see and study the formation of elements in the early galaxies of the Universe.

"Scientists can see the shadows of objects in front of the supermassive black hole," he said.

"Fast-growing supermassive black holes also help to clear the fog around them by ionising gases, which makes the Universe more transparent."

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Unusual laser emission from the Ant Nebula

The Ant Nebula, as imaged by the NASA/ESA Hubble Space Telescope, resembles the head and body of a garden ant. In reality, it's the result of a dying sun-like star and complex interactions of material at its heart.

An international team of astronomers have discovered an unusual laser emission that suggests the presence of a double star system hidden at the heart of the "spectacular" Ant Nebula.

The extremely rare phenomenon is connected to the death of a star and was discovered in observations made by European Space Agency's (ESA) Herschel space observatory.

When low- to middleweight stars like our Sun approach the end of their lives they eventually become dense, white dwarf stars. In the process, they cast off their outer layers of gas and dust into space, creating a kaleidoscope of intricate patterns known as a planetary nebula. Our Sun is expected to one day form such a planetary nebula.

A nebula is an interstellar cloud of dust, hydrogen, helium and other ionized gases. The Ant Nebula earns its nickname from the twin lobes that resemble the head and body of an ant.

The recent Herschel observations have shown that the dramatic demise of the central star in the core of the Ant Nebula is even more theatrical than implied by its colourful appearance in visible images -- such as those taken by the NASA/ESA Hubble Space Telescope.

The new data shows that the Ant Nebula also beams intense laser emission from its core. Lasers are well-known down on earth in everyday life, from special visual effects in music concerts to health care and communications. In space, laser emission is detected at very different wavelengths and only under certain conditions. Only a few of these infrared space lasers are known.

By coincidence, astronomer Donald Menzel who first observed and classified this particular planetary nebula in the 1920s (it is officially known as Menzel 3 after him) was also one of the first to suggest that in certain conditions natural 'light amplification by stimulated emission of radiation' -- from which the acronym 'laser' derives -- could occur in nebulae in space. This was well before the discovery of lasers in laboratories.

Dr Isabel Aleman, lead author of a paper describing the new results, said "We detected a very rare type of emission called hydrogen recombination laser emission, which is only produced in a narrow range of physical conditions.

"Such emission has only been identified in a handful of objects before and it is a happy coincidence that we detected the kind of emission that Menzel suggested, in one of the planetary nebulae that he discovered."

This kind of laser emission needs very dense gas close to the star. Comparison of the observations with models found that the density of the gas emitting the lasers is around ten thousand times denser than the gas seen in typical planetary nebulae and in the lobes of the Ant Nebula itself.

Normally, the region close to the dead star -- close in this case being about the distance of Saturn from the Sun -- is quite empty, because its material is ejected outwards. Any lingering gas would soon fall back onto it.

Co-author Prof Albert Zijlstra, from the Jodrell Bank Centre for Astrophysics at University of Manchester, added: "The only way to keep such dense gas close to the star is if it is orbiting around it in a disc. In this nebula, we have actually observed a dense disc in the very centre that is seen approximately edge-on. This orientation helps to amplify the laser signal.

"The disc suggests there is a binary companion, because it is hard to get the ejected gas to go into orbit unless a companion star deflects it in the right direction. The laser gives us a unique way to probe the disc around the dying star, deep inside the planetary nebula."

Astronomers have not yet seen the expected second star, hidden in the heart of the Ant nebula.

Göran Pilbratt, ESA's Herschel project scientist, added: "It is a nice conclusion that it took the Herschel mission to connect together Menzel's two discoveries from almost a century ago."

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World's fastest water heater: 100,000 degrees Celsius in less than a tenth of a picosecond

Scientists have used a powerful X-ray laser to heat water from room temperature to 100,000 degrees Celsius in less than a tenth of a picosecond (millionth of a millionth of a second). The experimental set-up, that can be seen as the world's fastest water heater, produced an exotic state of water, from which researchers hope to learn more about the peculiar characteristics of Earth's most important liquid. The observations also have practical use for the probing biological and many other samples with X-ray lasers. The team of Carl Caleman from the Center for Free-Electron Laser Science (CFEL) at DESY and Uppsala University (Sweden) reports its findings in the journal Proceedings of the National Academy of Sciences (PNAS).

The researchers used the X-ray free-electron laser Linac Coherent Light Source LCLS at the SLAC National Accelerator Laboratory in the U.S. to shoot extremely intense and ultra-short flashes of X-rays at a jet of water. "It is not the usual way to boil your water," said Caleman. "Normally, when you heat water, the molecules will just be shaken stronger and stronger." On the molecular level, heat is motion -- the hotter, the faster the motion of the molecules. This can be achieved, for example, via heat transfer from a stove, or more directly with microwaves that make the water molecules swing back and forth ever faster in step with the electromagnetic field.

"Our heating is fundamentally different," explained Caleman. "The energetic X-rays punch electrons out of the water molecules, thereby destroying the balance of electric charges. So, suddenly the atoms feel a strong repulsive force and start to move violently." In less than 75 femtoseconds, that's 75 millionths of a billionth of a second or 0.000 000 000 000 075 seconds, the water goes through a phase transition from liquid to plasma. A plasma is a state of matter where the electrons have been removed from the atoms, leading to a sort of electrically charged gas.

"But while the water transforms from liquid to plasma, it still remains at the density of liquid water, as the atoms didn't have time to move significantly yet," said co-author Olof Jönsson from Uppsala University. This exotic state of matter is nothing that can be found naturally on Earth. "It has similar characteristics as some plasmas in the sun and the gas giant Jupiter, but has a lower density. Meanwhile, it is hotter than Earth's core."

The scientists used their measurements to validate simulations of the process. Together, the measurements and simulations allow to study this exotic state of water in order to learn more about water's general properties. "Water really is an odd liquid, and if it weren't for its peculiar characteristics, many things on Earth wouldn't be as they are, particularly life," Jönsson emphasised. Water displays many anomalies, including its density, heat capacity and thermal conductivity. It it these anomalies that will be investigated within the future Centre for Water Science (CWS) planned at DESY, and the obtained results are of great importance for the acivities there.

Apart from its fundamental significance, the study also has immediate practical significance. X-ray lasers are often used to investigate the atomic structure of tiny samples. "It is important for any experiment involving liquids at X-ray lasers," said co-author Kenneth Beyerlein from CFEL. "In fact, any sample that you put into the X-ray beam will be destroyed in the way that we observed. If you analyse anything that is not a crystal, you have to consider this."

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Water plumes on Jupiter's moon Europa?

Scientists re-examining data from an old mission bring new insights to the tantalizing question of whether Jupiter's moon Europa has the ingredients to support life. The data provide independent evidence that the moon's subsurface liquid water reservoir may be venting plumes of water vapor above its icy shell.

Data collected by NASA's Galileo spacecraft in 1997 were put through new and advanced computer models to untangle a mystery -- a brief, localized bend in themagnetic field -- that had gone unexplained until now. Previous ultraviolet images from NASA's Hubble Space Telescope in 2012 suggested the presence of plumes, but this new analysis used data collected much closer to the source and is considered strong, corroborating support for plumes. The findings appear in Monday's issue of the journal Nature Astronomy.

The research was led by Xianzhe Jia, a space physicist at the University of Michigan in Ann Arbor and lead author of the journal article. Jia also is co-investigator for two instruments that will travel aboard Europa Clipper, NASA's upcoming mission to explore the moon's potential habitability.

"The data were there, but we needed sophisticated modeling to make sense of the observation," Jia said.

Jia's team was inspired to dive back into the Galileo data by Melissa McGrath of the SETI Institute in Mountain View, California. A member of the Europa Clipper science team, McGrath delivered a presentation to fellow team scientists, highlighting other Hubble observations of Europa.

"One of the locations she mentioned rang a bell. Galileo actually did a flyby of that location, and it was the closest one we ever had. We realized we had to go back," Jia said. "We needed to see whether there was anything in the data that could tell us whether or not there was a plume."

At the time of the 1997 flyby, about 124 miles (200 kilometers) above Europa's surface, the Galileo team didn't suspect the spacecraft might be grazing a plume erupting from the icy moon. Now, Jia and his team believe, its path was fortuitous.

When they examined the information gathered during that flyby 21 years ago, sure enough, high-resolution magnetometer data showed something strange. Drawing on what scientists learned from exploring plumes on Saturn's moon Enceladus -- that material in plumes becomes ionized and leaves a characteristic blip in the magnetic field -- they knew what to look for. And there it was on Europa -- a brief, localized bend in the magnetic field that had never been explained.

Galileo carried a powerful Plasma Wave Spectrometer to measure plasma waves caused by charged particles in gases around Europa's atmosphere. Jia's team pulled that data as well, and it also appeared to back the theory of a plume.

But numbers alone couldn't paint the whole picture. Jia layered the magnetometry and plasma wave signatures into new 3D modeling developed by his team at the University of Michigan, which simulated the interactions of plasma with solar system bodies. The final ingredient was the data from Hubble that suggested dimensions of potential plumes.

The result that emerged, with a simulated plume, was a match to the magnetic field and plasma signatures the team pulled from the Galileo data.

"There now seem to be too many lines of evidence to dismiss plumes at Europa," said Robert Pappalardo, Europa Clipper project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California. "This result makes the plumes seem to be much more real and, for me, is a tipping point. These are no longer uncertain blips on a faraway image."

The findings are good news for the Europa Clipper mission, which may launch as early as June 2022. From its orbit of Jupiter, Europa Clipper will sail close by the moon in rapid, low-altitude flybys. If plumes are indeed spewing vapor from Europa's ocean or subsurface lakes, Europa Clipper could sample the frozen liquid and dust particles. The mission team is gearing up now to look at potential orbital paths, and the new research will play into those discussions.

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Where hominid brains are concerned, size doesn't matter

The recently-discovered species Homo naledi may have had a pint-sized brain, but that brain packed a big punch. New research by Ralph Holloway and colleagues -- that include researchers from the University of the Witwatersrand, Johannesburg, South Africa -- published in the Proceedings of the National Academy of Sciences examines the imprints of the brain upon the skulls of this species, called endocasts. The research highlights the humanlike shape of naledi's tiny brain, surprising scientists who studied the fossils. These findings draw further into question the long-held belief that human evolution was an inevitable march towards bigger, more complex brains.

The discovery of Homo naledi by Professor Lee Berger of Wits University and his team at the Rising Star caves in the Cradle of Human Kind in 2013 was one of the largest hominin discoveries ever made and hailed as one of the most significant hominid discoveries of the 21st Century. Berger and Professor John Hawkes who was also part of the original Rising Star team who made the naledi discovery, as well as Professor Heather Garvin from Des Moines University in the US, are associated with the Evolutionary Studies Institute (ESI), based at Wits University. They are all co-authors of the current study.

In 2017, geologists demonstrated that this species existed in southern Africa between 236,000 and 335,000 years ago -- potentially the same time that modern humans first emerged in Africa. This is a puzzle to scientists, who long held that there was only one species in Africa at this late time period -- Homo sapiens. How did this species exist alongside others with brains three times its size? The new study suggests that naledi's behavior may have reflected the shape and structure of the brain more than its size.

The researchers pieced together traces of Homo naledi's brain shape from an extraordinary collection of skull fragments and partial crania, from at least five adult individuals. One of these bore a very clear imprint of the convolutions on the surface of the brain's left frontal lobe. "This is the skull I've been waiting for my whole career," said lead author Ralph Holloway, of Columbia University.

The anatomy of naledi's frontal lobe was similar to humans, and very different from great apes. Naledi wasn't alone. Other members of our genus, from Homo erectus to Homo habilis and the small-brained "hobbits," Homo floresiensis, also share features of the frontal lobe with living humans. But earlier human relatives, like Australopithecus africanus, had a much more apelike shape in this part of the brain, suggesting that functional changes in this brain region emerged with Homo. "It's too soon to speculate about language or communication in Homo naledi," said coauthor Shawn Hurst, "but today human language relies upon this brain region."

The back of the brain also showed humanlike changes in naledi compared to more primitive hominins like Australopithecus. Human brains are usually asymmetrical, with the left brain displaced forward relative to the right. The team found signs of this asymmetry in one of the most complete naledi skull fragments. They also found hints that the visual area of the brain, in the back of the cortex, was relatively smaller in naledi than in chimpanzees -- another humanlike trait.

The small brains of Homo naledi raise new questions about the evolution of human brain size. Big brains were costly to human ancestors, and some species may have paid the costs with richer diets, hunting and gathering, and longer childhoods. But that scenario doesn't seem to work well for Homo naledi, which had hands well-suited for toolmaking, long legs, humanlike feet, and teeth suggesting a high-quality diet. According to study coauthor John Hawks, "Naledi's brain seems like one you might predict for Homo habilis, two million years ago. But habilis didn't have such a tiny brain -- naledi did."

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Biologists 'transfer' a memory through RNA injection

UCLA biologists report they have transferred a memory from one marine snail to another, creating an artificial memory, by injecting RNA from one to another. This research could lead to new ways to lessen the trauma of painful memories with RNA and to restore lost memories.

"I think in the not-too-distant future, we could potentially use RNA to ameliorate the effects of Alzheimer's disease or post-traumatic stress disorder," said David Glanzman, senior author of the study and a UCLA professor of integrative biology and physiology and of neurobiology. The team's research is published May 14 in eNeuro, the online journal of the Society for Neuroscience.

RNA, or ribonucleic acid, has been widely known as a cellular messenger that makes proteins and carries out DNA's instructions to other parts of the cell. It is now understood to have other important functions besides protein coding, including regulation of a variety of cellular processes involved in development and disease.

The researchers gave mild electric shocks to the tails of a species of marine snail called Aplysia. The snails received five tail shocks, one every 20 minutes, and then five more 24 hours later. The shocks enhance the snail's defensive withdrawal reflex, a response it displays for protection from potential harm. When the researchers subsequently tapped the snails, they found those that had been given the shocks displayed a defensive contraction that lasted an average of 50 seconds, a simple type of learning known as "sensitization." Those that had not been given the shocks contracted for only about one second.

The life scientists extracted RNA from the nervous systems of marine snails that received the tail shocks the day after the second series of shocks, and also from marine snails that did not receive any shocks. Then the RNA from the first (sensitized) group was injected into seven marine snails that had not received any shocks, and the RNA from the second group was injected into a control group of seven other snails that also had not received any shocks.

Remarkably, the scientists found that the seven that received the RNA from snails that were given the shocks behaved as if they themselves had received the tail shocks: They displayed a defensive contraction that lasted an average of about 40 seconds.

"It's as though we transferred the memory," said Glanzman, who is also a member of UCLA's Brain Research Institute.

As expected, the control group of snails did not display the lengthy contraction.

Next, the researchers added RNA to Petri dishes containing neurons extracted from different snails that did not receive shocks. Some dishes had RNA from marine snails that had been given electric tail shocks, and some dishes contained RNA from snails that had not been given shocks. Some of the dishes contained sensory neurons, and others contained motor neurons, which in the snail are responsible for the reflex.

When a marine snail is given electric tail shocks, its sensory neurons become more excitable. Interestingly, the researchers discovered, adding RNA from the snails that had been given shocks also produced increased excitability in sensory neurons in a Petri dish; it did not do so in motor neurons. Adding RNA from a marine snail that was not given the tail shocks did not produce this increased excitability in sensory neurons.

In the field of neuroscience, it has long been thought that memories are stored in synapses. (Each neuron has several thousand synapses.) Glanzman holds a different view, believing that memories are stored in the nucleus of neurons.

"If memories were stored at synapses, there is no way our experiment would have worked," said Glanzman, who added that the marine snail is an excellent model for studying the brain and memory.

Scientists know more about the cell biology of this simple form of learning in this animal than any other form of learning in any other organism, Glanzman said. The cellular and molecular processes seem to be very similar between the marine snail and humans, even though the snail has about 20,000 neurons in its central nervous system and humans are thought to have about 100 billion.

In the future, Glanzman said, it is possible that RNA can be used to awaken and restore memories that have gone dormant in the early stages of Alzheimer's disease. He and his colleagues published research in the journal eLife in 2014 indicating that lost memories can be restored.

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How our ancestors with autistic traits led a revolution in Ice Age art

This is a drawing of a horse by Nadia, a gifted autistic child artist (left) and by a typically developing child of the same age (right).

The ability to focus on detail, a common trait among people with autism, allowed realism to flourish in Ice Age art, according to researchers at the University of York.

Around 30,000 years ago realistic art suddenly flourished in Europe. Extremely accurate depictions of bears, bison, horses and lions decorate the walls of Ice Age archaeological sites such as Chauvet Cave in southern France.

Why our ice age ancestors created exceptionally realistic art rather than the very simple or stylised art of earlier modern humans has long perplexed researchers.

Many have argued that psychotropic drugs were behind the detailed illustrations. The popular idea that drugs might make people better at art led to a number of ethically-dubious studies in the 60s where participants were given art materials and LSD.

The authors of the new study discount that theory, arguing instead that individuals with "detail focus," a trait linked to autism, kicked off an artistic movement that led to the proliferation of realistic cave drawings across Europe.

Lead author of the paper, Dr Penny Spikins from the Department of Archaeology at the University of York, said: "Detail focus is what determines whether you can draw realistically; you need it in order to be a talented realistic artist. This trait is found very commonly in people with autism and rarely occurs in people without it.

"We looked at the evidence from studies attempting to identify a link between artistic talent and drug use, and found that drugs can only serve to dis-inhibit individuals with a pre-existing ability. The idea that people with a high degree of detail focus, many of which may have had autism, set a trend for extreme realism in ice age art is a more convincing explanation."

The research adds to a growing body of evidence that people with autistic traits played an important role in human evolution.

Dr Spikins added: "Individuals with this trait -- both those who would be diagnosed with autism in the modern day and those that wouldn't -- likely played an important part in human evolution and survival as we colonised Europe.

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Snorers suffer from nerve and muscle damage in the palate

People who snore may have extensive tissue damage in the nerves and muscles of the soft palate. This can in turn create problems with swallowing and contribute to development of sleep apnea. Treatment strategies aimed at early intervention to stop snoring might have beneficial effects in healing or preventing development of sleep apnea. These findings are explained in a new dissertation at Umeå University, Sweden.

The reason why some develop sleep apnea is still unclear. Factors that are considered important are obesity, a small throat, neurological diseases and hormonal disorders. But even those without that background can suffer. The thesis shows that tissue damage in the soft palate also is an important factor that contributes to the development of sleep apnea and disturbances in swallowing function.

"The nerve and muscles injuries seem to contribute to the collapse of the upper airway during sleep. Most likely, the damage results from the recurrent snoring vibrations the tissues are exposed to, says Farhan Shah," PhD student at the Department of Integrative Medical Biology at Umeå University.

In his dissertation, Farhan Shah reports a study where his research team has examined eight patients who have been snoring for many years and 14 patients with snoring and sleep apnea. These have been compared to a control group of 18 non-snoring people. The subjects in the study were examined with overnight sleep registrations to detect sleep apnea. Disorders of the swallowing function were investigated with a video radiographic technique.

Tissue samples from the participants' soft palate were analyzed to detect muscle and nerve lesions. The results showed that snorers and sleep apnea patients had extensive damage in both nerves and muscles. The damage was related to the degree of swallowing disorders and the severity of sleep apnea.

The nerves in the soft palate of snorers and sleep apnea patients showed fewer nerve fibers and supporting cells that help the nerve fibers survive and regenerate. The nerves also had increased connective tissue. In muscle analysis, one could see that a large number of muscle fibers in the soft palate showed changes reflecting loss of innervation due to nerve damage.

It was also possible to see changes in the protein structures in the muscle fibers' cell membrane and cell skeleton of snorers and sleep apnea patients. Such changes give muscle weakness and have been previously found only in genetic muscle diseases.

"Continued research is needed to see if treatment that prevents damage to nerves and muscles could cure or at least prevent further deterioration in snores and sleep apnea patients. It would be a big win because sleep apnea is a major public illness," says Farhan Shah.

More than 400,000 Swedes suffer from sleep apnea. The condition is characterized by snoring and recurrent respiratory arrest during sleep. It creates a stress for the body and a proven risk increases for high blood pressure, cardiovascular diseases and premature death.

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Restoring epigenetic balance reinstates memory in flies with Alzheimer's disease symptoms

"When people age, they have a loss of memory but it's not because there are mutations in their genes," Elefant said. "It's the way they're packaged. They're distorted. And we're seeing non-invasive ways we might be able to prevent that early on."

Researchers from Drexel University reversed symptoms of Alzheimer's disease in fruit flies by restoring the balance between two epigenetic enzymes that regulate gene expression, a study shows.

Early in the progression of Alzheimer's disease, cognitive impairment (such as difficulties with learning and memory) may be tied to the presence of elevated levels of the HDAC2 enzyme. HDAC2 helps control how genes linked to learning and memory are expressed. It appears that when HDAC2 overwhelms the enzyme it is paired with, which is called Tip60 HAT, it represses genes and leads to problems with neuroplasticity -- the brain's ability to adapt to new stimuli or recall reactions to stimuli it already encountered.

But a research team led by Priyalakshmi Panikker, a PhD student, and Felice Elefant, PhD, an associate professor, both in Drexel's College of Arts and Sciences, performed tests in flies and found that if they added extra Tip60 HAT in the brain of flies that displayed symptoms close to Alzheimer's disease, the balance between the enzymes could be successfully restored. When that balance came back, behaviors the team had taught the flies were able to be learned again and remembered.

"Our findings strongly support the concept of exploring the efficacy of specific Tip60 HAT activators, as well as identifying and manipulating additionally misregulated Tip60 target genes," Elefant said.

Elefant, Panikker and their team -- whose findings were published in the Journal of Neuroscience - looked at how Alzheimer's disease affected flies early in their development, during their larval stages, to catch what might happen in Alzheimer's well before the tell-tale symptoms arise.

"Many researchers that study Alzheimer's disease utilize human post-mortem samples, and thus, they are not looking at what is happening during the early progression of neurodegeneration, including whether we can correct what is happening during these early stages ," Elefant said.

For the study, flies were taught to associate a certain odor with sucrose -- table sugar, which flies eat and is a positive reinforcement. After being exposed to the scent paired with sugar, the flies learned to move towards the scent even without the sugar present.

Flies that modeled Alzheimer's disease showed no difference in their reaction to the smell they had earlier been condition to. This showed that their ability to learn and remember this association was negatively affected.

But once Tip60 HAT was introduced in the brain to correct the identified Tip60 HAT/HDAC2 imbalance, these flies showed a reaction time comparable to the ones without the Alzheimer's type of condition. This indicated that they recovered their ability to learn and remember after the epigenetic balance was reintroduced.

Moreover, when researchers identified a collection of genes related to brain function that had been repressed in the flies -- due to elevated HDAC2 -- an introduction of increased Tip60 HAT levels in the brain restored regular function in 9 of the 11 genes tested.

The results Panikker and Elefant found were encouraging. More testing is needed, but Elefant's goal is to find new avenues for gene therapy.

Read more at Science Daily

Forensics: New tool predicts eye, hair and skin color from a DNA sample of an unidentified individual

An international team, led by scientists from the School of Science at IUPUI and Erasmus MC University Medical Center Rotterdam, has developed a novel tool to accurately predict eye, hair and skin color from human biological material. The innovative high-probability and high-accuracy complete pigmentation profile webtool is available online without charge.

An international team, led by scientists from the School of Science at IUPUI and Erasmus MC University Medical Center Rotterdam in the Netherlands, has developed a novel tool to accurately predict eye, hair and skin color from human biological material -- even a small DNA sample -- left, for example, at a crime scene or obtained from archeological remains. This all-in-one pigmentation profile tool provides a physical description of the person in a way that has not previously been possible by generating all three pigment traits together using a freely available webtool.

The tool is designed to be used when standard forensic DNA profiling is not helpful because no reference DNA exists against which to compare the evidence sample.

The HIrisPlex-S DNA test system is capable of simultaneously predicting eye, hair and skin color phenotypes from DNA. Users, such as law enforcement officials or anthropologists, can enter relevant data using a laboratory DNA analysis tool, and the webtool will predict the pigment profile of the DNA donor.

"We have previously provided law enforcement and anthropologists with DNA tools for eye color and for combined eye and hair color, but skin color has been more difficult," said forensic geneticist Susan Walsh from IUPUI, who co-directed the study. "Importantly, we are directly predicting actual skin color divided into five subtypes -- very pale, pale, intermediate, dark and dark to black -- using DNA markers from the genes that determine an individual's skin coloration. This is not the same as identifying genetic ancestry. You might say it's more similar to specifying a paint color in a hardware store rather than denoting race or ethnicity.

"If anyone asks an eyewitness what they saw, the majority of time they mention hair color and skin color. What we are doing is using genetics to take an objective look at what they saw," Walsh said.

The innovative high-probability and high-accuracy complete pigmentation profile webtool is available online without charge.

The study, "HIrisPlex-S System for Eye, Hair and Skin Colour Prediction from DNA: Introduction and Forensic Developmental Validation," is published in the peer-reviewed journal Forensic Science International: Genetics.

Read more at Science Daily

Alcohol and tobacco are by far the biggest threat to human welfare of all addictive drugs

A new review published online today in the journal Addiction has compiled the best, most up-to-date source of information on alcohol, tobacco, and illicit drug use and the burden of death and disease. It shows that in 2015 alcohol and tobacco use between them cost the human population more than a quarter of a billion disability-adjusted life years, with illicit drugs costing a further tens of millions.

The largest health burden from substance use was attributable to tobacco smoking and the smallest was attributable to illicit drugs. Global estimates suggest that nearly one in seven adults (15.2%) smoke tobacco and one in five adults report at least one occasion of heavy alcohol use in the past month.

Compared with the rest of the world, Central, Eastern, and Western Europe recorded consistently higher alcohol consumption per capita (11.61, 11.98 and 11.09 litres, respectively) and a higher percentage of heavy consumption amongst drinkers (50.5%, 48.2%, and 40.2%, respectively). The same European regions also recorded the highest prevalence of tobacco smoking (Eastern Europe 24.2%, Central Europe 23.7%, and Western Europe 20.9%).

In contrast, use of illicit drugs was far less common. Fewer than one in twenty people were estimated to use cannabis in the past year, and much lower estimates were observed for amphetamines, opioids and cocaine. Hotspots included the US, Canada, and Australasia. The US and Canada had one of the highest rates of cannabis, opioid, and cocaine dependence (748.7 [694.8, 812.3], 650.0 [574.5, 727.3], and 301.2 [269.3, 333.7] per 100,000 people, respectively). Australasia (Australia and New Zealand) had the highest prevalence of amphetamine dependence (491.5 per 100,000 people [441.4, 545.5]), as well as high rates of cannabis, opioid and cocaine use dependence (693.7 [648.1, 744.4], 509.9 [453.7, 577.8], and 160.5 [136.4, 187.1] per 100,000 people, respectively).

Some countries and regions (e.g., Africa, Caribbean and Latin America, Asia regions) have little or no data on substance use and associated health burden. These are typically low or middle income countries that frequently have punitive drug policies, and may experience serious political and social unrest. These countries need enhanced monitoring because they are at risk of rapid escalation in substance use and related health burden.

The report, 'Global Statistics on Alcohol, Tobacco, and Illicit Drug Use: 2017 Status Report', uses data mainly obtained from the World Health Organization, United Nations Office on Drugs and Crime, and Institute for Health Metrics and Evaluation. The authors note that there are important limitations to the data, especially for illicit drugs, but believe that putting all this information in one place will make it easier for governments and international agencies to develop policies to combat substance use.

From Science Daily

The evolution of conflict resolution

Recently published in the Journal of the Royal Society Interface, Assistant Professor Christoph Riedl's latest research examines a model that might explain how humans resolve conflict, and what these actions say about biological and social behavior, both now and into the future.

Dynamic networks allow individuals to resolve conflicts by managing their network connections rather than changing their strategy. This is a common phenomenon among humans who can make deliberate choices regarding who they want to interact with.

"Let's use an example: You're at a friend's house and you're both eating appetizers," explains Riedl. "When only one appetizer is left, how do you decide who gets it? If you both really want it, then you are involved in a potential conflict, and there are several socially accepted ways of solving the issue. But which norm should you settle on, and why?"

With these social constructs in mind, Riedl's research started by looking at traditional games of conflict, such as "the game of chicken," and applying computer simulations to examine how disagreements get resolved efficiently to encourage cooperation.

These simulations showed Riedl and his team -- Tufts University Associate Professor of Philosophy Rory Smead, Northeastern University Associate Professor of Philosophy Patrick Forber, and Network Science Institute PhD student Michael Foley -- that one social solution far outweighs the other, instead of both behaviors being exhibited equally.

"Host-guest norms or 'paradoxical behavior' account for the vast majority of our simulated final state solutions -- in other words, the host gives the guest the last appetizer," says Riedl. "The opposite solution where the host takes the appetizer for himself, called ownership norms or 'bourgeois behavior,' is quite rare."

"This is especially interesting in the context of human biological behavior because in the animal kingdom, territoriality or ownership norms are ubiquitous."

And so, how and why did the host-guest norm evolve into the more socially accepted conflict resolution in human beings, and how might that affect the future? The research suggests that this is due to the dynamic nature of the social network which allows actors to choose their interaction partners. This entails that insofar ownership and territoriality are probably widespread due to the intrinsic importance of holding resources or the value of owning a territory rather than as a convention for avoiding conflict. Riedl and his fellow researchers are hard at work to unveil additional details about the evolutionary dynamics of when or where certain conventions may arise.

From Science Daily