Figuring out what lies ahead for our species and our planet is one of the most pressing and challenging tasks for climate scientists. While models are very useful, there is nothing quite like Earth's history to reveal details about how oceans, animals, and plants respond to and recover from a warming world.
The two most recent major global warming events are especially instructive -- and worrisome, say scientists presenting new research Wednesday at the Annual Meeting of the Geological Society of America.
Ancient analogs
The two past climate crises that are comparable to today's happened 56 and 66 million years ago. The earlier one, the Cretaceous-Paleogene boundary (KPB) mass extinction, is infamous for ending the reign of the dinosaurs. The later event, called the Paleocene-Eocene Thermal Maximum (PETM) was relatively less severe, and provides clues to how the world can recover from such difficult times.
"We chose these two because they are the most recent examples of rapid climate warming and have been widely studied so we have more information about them," said Paula Mateo, a geologist at Caltech, who will be presenting the study on Wednesday.
Both ancient global warming events were, like today, caused by the release of greenhouse gases -- a.k.a. carbon emissions -- into the atmosphere. The sources in the past were not fossil fuel burning however, but related to very large and long volcanic eruptions -- unlike any that have occurred during the time humans have existed.
The geologic evidence suggests that the carbon emissions that preceded the dinosaurs' demise were at an average rate of about 0.2 to 3 gigatons per year. The PETM recorded carbon emissions of less than 1.1 gigatons per year, Mateo said. Those numbers are dwarfed next to humanity's emission rate of 10 gigatons per year, she added.
Dino killer?
The KPB mass extinction event is often attributed solely to the Chicxulub meteor impact in Mexico, but there is a growing body of evidence suggesting that the massive eruption of the Deccan Traps in India also played a role. That mega-eruption flowed across India in pulse after pulse, lasting about 750,000 years. A full 280,000 years before the extinction event the oceans had warmed 3 to 4 degrees Celsius while on land the warming was of 6 to 8 degrees C because of the eruptions. Volcanic activity accelerated during the last 25,000 years before the mass extinction, Mateo said, steadily releasing more carbon dioxide into the atmosphere. Those pulses added another 2.5 degrees C to the global temperature.
"This series of mega-pulses didn't let the ecosystems adapt or even survive," Mateo said. Fossil evidence suggests that the warming and ocean acidification stressed life on land and oceans, eventually contributing to one of the five mass extinction events in the history of the planet. Microfossils of the oceans' foraminifers, which are part of the base of the marine food chain, show signs that they were struggling leading up the end of the Cretaceous period and then 66% went extinct at the KPB, 33% survived but rapidly disappeared during the first 100,000 years after the KPB, and only one species survived in the long term. On land warming during the last 280,000 years of the Cretaceous appears to have started a decline in dinosaurs as well in early mammals, insects, and amphibians well prior to the last mega-eruptions ending with the KPB mass extinction.
Ocean-building event
The more recent PETM, for its part, was caused by the expansion of the North Atlantic Ocean basin. That involved a lot of magma rising up from below to become the new ocean crust. All that magma released a lot of carbon dioxide, which appears to have caused moderate warming that, in turn, triggered the melting of clathrates -- frozen methane hydrate deposits in the ocean floor. The methane emissions supercharged the greenhouse situation and led to a 5 degree C spike of warming.
That warming was hard on living things on land and sea, but it wasn't a series of blows, like what led to the KPB. Many animals were able to adapt or migrate and avoid the harshest conditions. It was a single blow with environmental consequences that lasted about 200,000 years but there wasn't a mass extinction event.
The best analog
Listed side-by-side, it's sobering to see how many of the same ecosystem effects of the KPB and PETM are now being played out in the oceans and on land in real time as a result of anthropogenic warming.
"The difference with today is that even though it's a very short pulse, the rate of change is very, very rapid," said Mateo. "It's happening so fast that the ecosystems are unable to catch up. There is no time for adaptation."
So while today's greenhouse warming is a single pulse, as in the PETM, it is happening orders of magnitude faster, which could be creating effects more like those of the KPB.
Read more at Science Daily
Sep 24, 2019
Evolution experiment: Specific immune response of beetles adapts to bacteria
When the immune system fends off pathogens, this can happen in a very wide variety of ways. For example, the immune system's memory is able to distinguish a foreign protein with which the organism has already come into contact from another and to react with a corresponding antibody. Researchers have now investigated experimentally whether this ability of the immune system to specifically fend off pathogens can adapt in the course of evolution. To this end, they studied many successive generations of flour beetles -- because insects can also specifically repel pathogens to a certain degree.
After the researchers repeatedly confronted the insects and their progeny with bacteria, they observed that the beetles' immune system reacted more strongly after just a few generations. "Our study helps us to understand whether an immune system's specificity ability can adapt quickly to the conditions of repeated confrontation with pathogens," says Prof. Joachim Kurtz from Münster University, who is heading the study.
The results might be able to help provide a better understanding of molecular processes that play a role in the innate immune memory in humans and that could perhaps be used for medical purposes. As insects are well suited for experimental evolution, the information thus acquired could usefully complement existing knowledge on the immune system of mammals. The study has been published in the journal "PNAS" (Proceedings of the National Academy of Sciences).
Background and method:
The immune system in human beings consists of two main systems -- the innate immune system and the adaptive one. The latter is the part which primarily "remembers" pathogens and can react specifically. Insects have a different immune system, but researchers have already been able to show that insects too are able to show a greater reaction to infections as a result of previous experience with pathogens. However, it has not yet been investigated whether this immunological specificity can adapt evolutionarily to the respective bacterial environment.
For their experiment, the evolutionary biologists collected data from more than 48,000 red flour beetles over a period of three years. They divided the beetles into different groups in order to expose them to different combinations of six different bacterial species in each case in the larval stage first killed and then living bacteria. In some of the groups, the researchers used the same bacteria within one generation; in the other groups they confronted the beetles with a variety of different bacteria. 14 generations and three years later, they produced the results of the experiment: beetles which had been exposed to the same type of bacteria for "vaccination" and infection had developed a higher specificity over generations. This helped the beetles especially whenever they had to defend themselves against Bacillus thuringiensis, a natural insect pathogen.
The increased specificity was demonstrated by the fact that after "vaccination" with this natural pathogen, a greater activation of certain genes could be detected which play a role for the immune system and metabolism. At the same time, the survival chances of the beetles rose after being infected with the bacterium -- in contrast to beetles that had evolved towards a low specificity. "This means that for certain bacteria a high specificity can develop quickly during evolution -- probably caused by changes in the immune genes," say the lead authors, Dr. Kevin Ferro and Dr. Robert Peuß, who carried out the experiments as part of their PhDs at the Institute of Evolution and Biodiversity at Münster University. It was noticeable, however, that this change did not occur in all bacteria used in the experiment. One possible explanation for this might be the limited opportunities of insects to recognize and combat various antigens.
Relevance and prospects:
The molecular mechanisms identified in this experiment could be relevant for humans -- in so-called 'trained immunity', a possibility being discussed in medicine for training the memory not only of the acquired, but also of the innate part of the immune system. Based on the newly acquired genetic data, the researchers want to take a more precise look at the immune memory of insects and "deactivate" the relevant genes using molecular-biological methods. In future, the researchers also want to examine the bacteria to see whether for example they develop faster when their host is prepared for them. As flour beetles are seen as a pest in food production, among others, the researchers' results could help to find a new strategy to combat them.
Read more at Science Daily
After the researchers repeatedly confronted the insects and their progeny with bacteria, they observed that the beetles' immune system reacted more strongly after just a few generations. "Our study helps us to understand whether an immune system's specificity ability can adapt quickly to the conditions of repeated confrontation with pathogens," says Prof. Joachim Kurtz from Münster University, who is heading the study.
The results might be able to help provide a better understanding of molecular processes that play a role in the innate immune memory in humans and that could perhaps be used for medical purposes. As insects are well suited for experimental evolution, the information thus acquired could usefully complement existing knowledge on the immune system of mammals. The study has been published in the journal "PNAS" (Proceedings of the National Academy of Sciences).
Background and method:
The immune system in human beings consists of two main systems -- the innate immune system and the adaptive one. The latter is the part which primarily "remembers" pathogens and can react specifically. Insects have a different immune system, but researchers have already been able to show that insects too are able to show a greater reaction to infections as a result of previous experience with pathogens. However, it has not yet been investigated whether this immunological specificity can adapt evolutionarily to the respective bacterial environment.
For their experiment, the evolutionary biologists collected data from more than 48,000 red flour beetles over a period of three years. They divided the beetles into different groups in order to expose them to different combinations of six different bacterial species in each case in the larval stage first killed and then living bacteria. In some of the groups, the researchers used the same bacteria within one generation; in the other groups they confronted the beetles with a variety of different bacteria. 14 generations and three years later, they produced the results of the experiment: beetles which had been exposed to the same type of bacteria for "vaccination" and infection had developed a higher specificity over generations. This helped the beetles especially whenever they had to defend themselves against Bacillus thuringiensis, a natural insect pathogen.
The increased specificity was demonstrated by the fact that after "vaccination" with this natural pathogen, a greater activation of certain genes could be detected which play a role for the immune system and metabolism. At the same time, the survival chances of the beetles rose after being infected with the bacterium -- in contrast to beetles that had evolved towards a low specificity. "This means that for certain bacteria a high specificity can develop quickly during evolution -- probably caused by changes in the immune genes," say the lead authors, Dr. Kevin Ferro and Dr. Robert Peuß, who carried out the experiments as part of their PhDs at the Institute of Evolution and Biodiversity at Münster University. It was noticeable, however, that this change did not occur in all bacteria used in the experiment. One possible explanation for this might be the limited opportunities of insects to recognize and combat various antigens.
Relevance and prospects:
The molecular mechanisms identified in this experiment could be relevant for humans -- in so-called 'trained immunity', a possibility being discussed in medicine for training the memory not only of the acquired, but also of the innate part of the immune system. Based on the newly acquired genetic data, the researchers want to take a more precise look at the immune memory of insects and "deactivate" the relevant genes using molecular-biological methods. In future, the researchers also want to examine the bacteria to see whether for example they develop faster when their host is prepared for them. As flour beetles are seen as a pest in food production, among others, the researchers' results could help to find a new strategy to combat them.
Read more at Science Daily
Machu Picchu: Ancient Incan sanctuary intentionally built on faults
 |
| Machu Picchu, Peru |
On Monday, 23 Sept. 2019, at the GSA Annual meeting in Phoenix, Rualdo Menegat, a geologist at Brazil's Federal University of Rio Grande do Sul, will present the results of a detailed geoarchaeological analysis that suggests the Incas intentionally built Machu Picchu -- as well as some of their cities -- in locations where tectonic faults meet. "Machu Pichu's location is not a coincidence," says Menegat. "It would be impossible to build such a site in the high mountains if the substrate was not fractured."
Using a combination of satellite imagery and field measurements, Menegat mapped a dense web of intersecting fractures and faults beneath the UNESCO World Heritage Site. His analysis indicates these features vary widely in scale, from tiny fractures visible in individual stones to major, 175-kilometer-long lineaments that control the orientation of some of the region's river valleys.
Menegat found that these faults and fractures occur in several sets, some of which correspond to the major fault zones responsible for uplifting the Central Andes Mountains during the past eight million years. Because some of these faults are oriented northeast-southwest and others trend northwest-southeast, they collectively create an "X" shape where they intersect beneath Machu Picchu.
Menegat's mapping suggests that the sanctuary's urban sectors and the surrounding agricultural fields, as well as individual buildings and stairs, are all oriented along the trends of these major faults. "The layout clearly reflects the fracture matrix underlying the site," says Menegat. Other ancient Incan cities, including Ollantaytambo, Pisac, and Cusco, are also located at the intersection of faults, says Menegat. "Each is precisely the expression of the main directions of the site's geological faults."
Menegat's results indicate the underlying fault-and-fracture network is as integral to Machu Picchu's construction as its legendary stonework. This mortar-free masonry features stones so perfectly fitted together that it's impossible to slide a credit card between them. As master stoneworkers, the Incas took advantage of the abundant building materials in the fault zone, says Menegat. "The intense fracturing there predisposed the rocks to breaking along these same planes of weakness, which greatly reduced the energy needed to carve them."
In addition to helping shape individual stones, the fault network at Machu Picchu likely offered the Incas other advantages, according to Menegat. Chief among these was a ready source of water. "The area's tectonic faults channeled meltwater and rainwater straight to the site," he says. Construction of the sanctuary in such a high perch also had the benefit of isolating the site from avalanches and landslides, all-too-common hazards in this alpine environment, Menegat explains.
Read more at Science Daily
Did mosasaurs do the breast stroke?
 |
| Illustration of an extinct mosasaur |
Now, new research suggests that mosasaurs had yet another potent advantage: a muscular breast stroke that may have added ambush-worthy bursts of speed.
"We know that mosasaurs most likely used their tails for locomotion. Now we think that they also used their forelimbs, or their tail and forelimbs together," explains lead author Kiersten Formoso, a Ph.D. student in vertebrate paleontology at the University of Southern California. That dual swimming style, she says, could make mosasaurs unique among tetrapods (four limbed creatures), living or extinct.
Previous studies noted that mosasaurs had an unusually large pectoral girdle -- the suite of bones that support the forelimbs. But most assumed the creature's swimming was mainly driven by their long tails, something like alligators or whales. That smooth, long distance-adapted swimming style is called "cruising," as opposed to "burst" motion. "Like anything that swims or flies, the laws of fluid dynamics mean that burst versus cruising is a tradeoff," explains co-author Mike Habib, Assistant Professor of Anatomical Sciences at USC. "Not many animals are good at both."
To dive in more closely on whether mosasaurs were burst-adapted, cruise-adapted, or an unusual balance of both, Formoso and co-authors focused on the oversized pectoral girdle. They studied a fossil Plotosaurus, a type of mosasaur, at the Natural History Museum of Los Angeles County. In addition, they used measurements of mosasaur pectoral girdles published in other studies.
They determined that the mosasaurs' unusually large and low-placed pectoral girdle supported large muscle attachments. In addition, says Habib, asymmetry in the bone structure is a telltale sign of the strong, inward pull-down motion called adduction. These analyses suggest that mosasaurs used their forelimbs to swim, breast-stroke style, adding powerful bursts of propulsion to their ability to cruise.
The team continues to model bone structure, morphology, measurements, and fluid dynamics such as drag to learn exactly how, and how fast, these sea monsters swam. Along with applications to biomechanics, and even robotics, say Formoso and Habib, the study also sheds light on how evolution and ecosystems are affected by fluid dynamics.
Read more at Science Daily
Sep 23, 2019
Is theory on Earth's climate in the last 15 million years wrong?
A key theory that attributes the climate evolution of the Earth to the breakdown of Himalayan rocks may not explain the cooling over the past 15 million years, according to a Rutgers-led study.
The study in the journal Nature Geoscience could shed more light on the causes of long-term climate change. It centers on the long-term cooling that occurred before the recent global warming tied to greenhouse gas emissions from humanity.
"The findings of our study, if substantiated, raise more questions than they answered," said senior author Yair Rosenthal, a distinguished professor in the Department of Marine and Coastal Sciences in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick. "If the cooling is not due to enhanced Himalayan rock weathering, then what processes have been overlooked?"
For decades, the leading hypothesis has been that the collision of the Indian and Asian continents and uplifting of the Himalayas brought fresh rocks to the Earth's surface, making them more vulnerable to weathering that captured and stored carbon dioxide -- a key greenhouse gas. But that hypothesis remains unconfirmed.
Lead author Weimin Si, a former Rutgers doctoral student now at Brown University, and Rosenthal challenge the hypothesis and examined deep-sea sediments rich with calcium carbonate.
Over millions of years, the weathering of rocks captured carbon dioxide and rivers carried it to the ocean as dissolved inorganic carbon, which is used by algae to build their calcium carbonate shells. When algae die, their skeletons fall on the seafloor and get buried, locking carbon from the atmosphere in deep-sea sediments.
If weathering increases, the accumulation of calcium carbonate in the deep sea should increase. But after studying dozens of deep-sea sediment cores through an international ocean drilling program, Si found that calcium carbonate in shells decreased significantly over 15 million years, which suggests that rock weathering may not be responsible for the long-term cooling.
Meanwhile, the scientists -- surprisingly -- also found that algae called coccolithophores adapted to the carbon dioxide decline over 15 million years by reducing their production of calcium carbonate. This reduction apparently was not taken into account in previous studies.
Many scientists believe that ocean acidification from high carbon dioxide levels will reduce the calcium carbonate in algae, especially in the near future. The data, however, suggest the opposite occurred over the 15 million years before the current global warming spell.
Read more at Science Daily
The study in the journal Nature Geoscience could shed more light on the causes of long-term climate change. It centers on the long-term cooling that occurred before the recent global warming tied to greenhouse gas emissions from humanity.
"The findings of our study, if substantiated, raise more questions than they answered," said senior author Yair Rosenthal, a distinguished professor in the Department of Marine and Coastal Sciences in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick. "If the cooling is not due to enhanced Himalayan rock weathering, then what processes have been overlooked?"
For decades, the leading hypothesis has been that the collision of the Indian and Asian continents and uplifting of the Himalayas brought fresh rocks to the Earth's surface, making them more vulnerable to weathering that captured and stored carbon dioxide -- a key greenhouse gas. But that hypothesis remains unconfirmed.
Lead author Weimin Si, a former Rutgers doctoral student now at Brown University, and Rosenthal challenge the hypothesis and examined deep-sea sediments rich with calcium carbonate.
Over millions of years, the weathering of rocks captured carbon dioxide and rivers carried it to the ocean as dissolved inorganic carbon, which is used by algae to build their calcium carbonate shells. When algae die, their skeletons fall on the seafloor and get buried, locking carbon from the atmosphere in deep-sea sediments.
If weathering increases, the accumulation of calcium carbonate in the deep sea should increase. But after studying dozens of deep-sea sediment cores through an international ocean drilling program, Si found that calcium carbonate in shells decreased significantly over 15 million years, which suggests that rock weathering may not be responsible for the long-term cooling.
Meanwhile, the scientists -- surprisingly -- also found that algae called coccolithophores adapted to the carbon dioxide decline over 15 million years by reducing their production of calcium carbonate. This reduction apparently was not taken into account in previous studies.
Many scientists believe that ocean acidification from high carbon dioxide levels will reduce the calcium carbonate in algae, especially in the near future. The data, however, suggest the opposite occurred over the 15 million years before the current global warming spell.
Read more at Science Daily
Green tea could hold the key to reducing antibiotic resistance
Scientists at the University of Surrey have discovered that a natural antioxidant commonly found in green tea can help eliminate antibiotic resistant bacteria.
The study, published in the Journal of Medical Microbiology, found that epigallocatechin (EGCG) can restore the activity of aztreonam, an antibiotic commonly used to treat infections caused by the bacterial pathogen Pseudomonas aeruginosa.
P. aeruginosa is associated with serious respiratory tract and bloodstream infections and in recent years has become resistant to many major classes of antibiotics. Currently a combination of antibiotics is used to fight P. aeruginosa.
However, these infections are becoming increasingly difficult to treat, as resistance to last line antibiotics is being observed.
To assess the synergy of EGCG and aztreonam, researchers conducted in vitro tests to analyse how they interacted with the P. aeruginosa, individually and in combination. The Surrey team found that the combination of aztreonam and EGCG was significantly more effective at reducing P. aeruginosa numbers than either agent alone.
This synergistic activity was also confirmed in vivo using Galleria mellonella (Greater Wax Moth larvae), with survival rates being significantly higher in those treated with the combination than those treated with EGCG or aztreonam alone. Furthermore, minimal to no toxicity was observed in human skin cells and in Galleria mellonella larvae.
Researchers believe that in P. aeruginosa, EGCG may facilitate increased uptake of aztreonam by increasing permeability in the bacteria. Another potential mechanism is EGCG's interference with a biochemical pathway linked to antibiotic susceptibility.
Lead author Dr Jonathan Betts, Senior Research Fellow in the School of Veterinary Medicine at the University of Surrey, said:
"Antimicrobial resistance (AMR) is a serious threat to global public health. Without effective antibiotics, the success of medical treatments will be compromised. We urgently need to develop novel antibiotics in the fight against AMR. Natural products such as EGCG, used in combination with currently licenced antibiotics, may be a way of improving their effectiveness and clinically useful lifespan."
Professor Roberto La Ragione, Head of the Department of Pathology and Infectious Diseases in the School of Veterinary Medicine at the University of Surrey, said:
"The World Health Organisation has listed antibiotic resistant Pseudomonas aeruginosa as a critical threat to human health. We have shown that we can successfully eliminate such threats with the use of natural products, in combination with antibiotics already in use. Further development of these alternatives to antibiotics may allow them to be used in clinical settings in the future."
From Science Daily
The study, published in the Journal of Medical Microbiology, found that epigallocatechin (EGCG) can restore the activity of aztreonam, an antibiotic commonly used to treat infections caused by the bacterial pathogen Pseudomonas aeruginosa.
P. aeruginosa is associated with serious respiratory tract and bloodstream infections and in recent years has become resistant to many major classes of antibiotics. Currently a combination of antibiotics is used to fight P. aeruginosa.
However, these infections are becoming increasingly difficult to treat, as resistance to last line antibiotics is being observed.
To assess the synergy of EGCG and aztreonam, researchers conducted in vitro tests to analyse how they interacted with the P. aeruginosa, individually and in combination. The Surrey team found that the combination of aztreonam and EGCG was significantly more effective at reducing P. aeruginosa numbers than either agent alone.
This synergistic activity was also confirmed in vivo using Galleria mellonella (Greater Wax Moth larvae), with survival rates being significantly higher in those treated with the combination than those treated with EGCG or aztreonam alone. Furthermore, minimal to no toxicity was observed in human skin cells and in Galleria mellonella larvae.
Researchers believe that in P. aeruginosa, EGCG may facilitate increased uptake of aztreonam by increasing permeability in the bacteria. Another potential mechanism is EGCG's interference with a biochemical pathway linked to antibiotic susceptibility.
Lead author Dr Jonathan Betts, Senior Research Fellow in the School of Veterinary Medicine at the University of Surrey, said:
"Antimicrobial resistance (AMR) is a serious threat to global public health. Without effective antibiotics, the success of medical treatments will be compromised. We urgently need to develop novel antibiotics in the fight against AMR. Natural products such as EGCG, used in combination with currently licenced antibiotics, may be a way of improving their effectiveness and clinically useful lifespan."
Professor Roberto La Ragione, Head of the Department of Pathology and Infectious Diseases in the School of Veterinary Medicine at the University of Surrey, said:
"The World Health Organisation has listed antibiotic resistant Pseudomonas aeruginosa as a critical threat to human health. We have shown that we can successfully eliminate such threats with the use of natural products, in combination with antibiotics already in use. Further development of these alternatives to antibiotics may allow them to be used in clinical settings in the future."
From Science Daily
Soap from straw: Scientists develop eco friendly ingredient from agricultural waste
A scientist has discovered a way of using one of the world's most abundant natural resources as a replacement for humanmade chemicals in soaps and thousands of other household products.
An innovative research project, published this month and led by the University of Portsmouth, has demonstrated that bails of rice straw could create a 'biosurfacant', providing an alternative non-toxic ingredient in the production of a vast variety of products that normally include synthetic materials which are often petroleum based.
The biotechnology project set out to solve one of the planet's most pressing environmental problems, looking for a way of reducing the amount of humanmade chemicals in everyday life. It has been co-supervised by the University of Portsmouth's Centre for Enzyme Innovation, working in conjunction with Amity University in India and the Indian Institute of Technology.
The study was looking for a natural replacement for chemical surfactants, a main active ingredient in the production of cleaning products, medicine, suncream, make-up and insecticides. The surfactant holds oil and water together, helping to lower the surface tension of a liquid, aiding the cleaning power and penetration of the product.
Dr Pattanathu Rahman, microbial biotechnologist from the University of Portsmouth and Director of TeeGene, worked with academics and PhD Scholar Mr Sam Joy from 2015 to create a biosurfacant by brewing rice straw with enzymes. The scientists believe this environmentally friendly method results in a high quality ingredient that manufacturing industries are crying out for.
Dr Rahman said: "Surfactants are everywhere, including detergent, fabric softener, glue insecticides, shampoo, toothpaste, paint, laxatives and make up. Imagine if we could make and manufacture biosurfacants in sufficient quantities to use instead of surfactants, taking the humanmade chemical bonds out of these products. This research shows that with the use of agricultural waste such as rice straws, which is in plentiful supply, we are a step closer."
Scientists behind the research believe the use of biosurfactants created from rice straw or other agricultural waste could have a positive ecological effect in a number of ways:
Dr Rahman explains: "The levels of purity needed for biosurfactants in the industries in which they're used is extremely high. Because of this, they can be very expensive. However, the methods we have of producing them make it much more economical and cost efficient. It's a very exciting technology with tremendous potential for applications in a range of industries."
The study shows that biosurfactants could be a potential alternative for the synthetic surfactant molecules, with a market value of $US2.8 billion in 2023. The considerable interest in biosurfactants in recent years is also due to their low toxicity, biodegradable nature and specificity, which would help them meet the European Surfactant Directive.
Dr Rahman says the process of producing biosurfacants calls for new attitudes to soap and cleaning products.
Read more at Science Daily
An innovative research project, published this month and led by the University of Portsmouth, has demonstrated that bails of rice straw could create a 'biosurfacant', providing an alternative non-toxic ingredient in the production of a vast variety of products that normally include synthetic materials which are often petroleum based.
The biotechnology project set out to solve one of the planet's most pressing environmental problems, looking for a way of reducing the amount of humanmade chemicals in everyday life. It has been co-supervised by the University of Portsmouth's Centre for Enzyme Innovation, working in conjunction with Amity University in India and the Indian Institute of Technology.
The study was looking for a natural replacement for chemical surfactants, a main active ingredient in the production of cleaning products, medicine, suncream, make-up and insecticides. The surfactant holds oil and water together, helping to lower the surface tension of a liquid, aiding the cleaning power and penetration of the product.
Dr Pattanathu Rahman, microbial biotechnologist from the University of Portsmouth and Director of TeeGene, worked with academics and PhD Scholar Mr Sam Joy from 2015 to create a biosurfacant by brewing rice straw with enzymes. The scientists believe this environmentally friendly method results in a high quality ingredient that manufacturing industries are crying out for.
Dr Rahman said: "Surfactants are everywhere, including detergent, fabric softener, glue insecticides, shampoo, toothpaste, paint, laxatives and make up. Imagine if we could make and manufacture biosurfacants in sufficient quantities to use instead of surfactants, taking the humanmade chemical bonds out of these products. This research shows that with the use of agricultural waste such as rice straws, which is in plentiful supply, we are a step closer."
Scientists behind the research believe the use of biosurfactants created from rice straw or other agricultural waste could have a positive ecological effect in a number of ways:
- There is significant concern about the impact of the chemical surfactants used in household products, most of which ends up in the oceans.
- Rice straw is a natural by-product of the rice harvest, with millions of tonnes created worldwide every year.
- Farmers often burn the waste producing harmful environmental emissions. Using it to create another product could be an efficient and beneficial recycling process.
- There could also be an economic advantage to using biosurfacants produced from agricultural waste.
Dr Rahman explains: "The levels of purity needed for biosurfactants in the industries in which they're used is extremely high. Because of this, they can be very expensive. However, the methods we have of producing them make it much more economical and cost efficient. It's a very exciting technology with tremendous potential for applications in a range of industries."
The study shows that biosurfactants could be a potential alternative for the synthetic surfactant molecules, with a market value of $US2.8 billion in 2023. The considerable interest in biosurfactants in recent years is also due to their low toxicity, biodegradable nature and specificity, which would help them meet the European Surfactant Directive.
Dr Rahman says the process of producing biosurfacants calls for new attitudes to soap and cleaning products.
Read more at Science Daily
Cats are securely bonded to their people, too
Cats have a reputation for being aloof and independent. But a study of the way domestic cats respond to their caregivers suggests that their socio-cognitive abilities and the depth of their human attachments have been underestimated.
The findings reported in the journal Current Biology on September 23 show that, much like children and dogs, pet cats form secure and insecure bonds with their human caretakers. The findings suggest that this bonding ability across species must be explained by traits that aren't specific to canines, the researchers say.
"Like dogs, cats display social flexibility in regard to their attachments with humans," said Kristyn Vitale of Oregon State University. "The majority of cats are securely attached to their owner and use them as a source of security in a novel environment."
One revealing way to study human attachment behavior is to observe an infant's response to a reunion with their caregiver following a brief absence in a novel environment. When a caregiver returns, secure infants quickly return to relaxed exploration while insecure individuals engage in excessive clinging or avoidance behavior.
Similar tests had been run before with primates and dogs, so Vitale and her colleagues decided to run the same test, only this time with cats.
During the test, an adult cat or kitten spent two minutes in a novel room with their caregiver followed by two minutes alone. Then, they had a two-minute reunion. The cats' responses to seeing their owners again were classified into attachment styles.
The results show that cats bond in a way that's surprisingly similar to infants. In humans, 65 percent of infants are securely attached to their caregiver.
"Domestic cats mirrored this very closely," Vitale says. In fact, they classified about 65 percent of both cats and kittens as securely bonded to their people.
The findings show that cats' human attachments are stable and present in adulthood. This social flexibility may have helped facilitate the success of the species in human homes, Vitale says.
The researchers are now exploring the importance of this work in relation to the thousands of kittens and cats that wind up in animal shelters. "We're currently looking at several aspects of cat attachment behavior, including whether socialization and fostering opportunities impact attachment security in shelter cats," Vitale said.
From Science Daily
The findings reported in the journal Current Biology on September 23 show that, much like children and dogs, pet cats form secure and insecure bonds with their human caretakers. The findings suggest that this bonding ability across species must be explained by traits that aren't specific to canines, the researchers say.
"Like dogs, cats display social flexibility in regard to their attachments with humans," said Kristyn Vitale of Oregon State University. "The majority of cats are securely attached to their owner and use them as a source of security in a novel environment."
One revealing way to study human attachment behavior is to observe an infant's response to a reunion with their caregiver following a brief absence in a novel environment. When a caregiver returns, secure infants quickly return to relaxed exploration while insecure individuals engage in excessive clinging or avoidance behavior.
Similar tests had been run before with primates and dogs, so Vitale and her colleagues decided to run the same test, only this time with cats.
During the test, an adult cat or kitten spent two minutes in a novel room with their caregiver followed by two minutes alone. Then, they had a two-minute reunion. The cats' responses to seeing their owners again were classified into attachment styles.
The results show that cats bond in a way that's surprisingly similar to infants. In humans, 65 percent of infants are securely attached to their caregiver.
"Domestic cats mirrored this very closely," Vitale says. In fact, they classified about 65 percent of both cats and kittens as securely bonded to their people.
The findings show that cats' human attachments are stable and present in adulthood. This social flexibility may have helped facilitate the success of the species in human homes, Vitale says.
The researchers are now exploring the importance of this work in relation to the thousands of kittens and cats that wind up in animal shelters. "We're currently looking at several aspects of cat attachment behavior, including whether socialization and fostering opportunities impact attachment security in shelter cats," Vitale said.
From Science Daily
Sep 22, 2019
Atlantic Ocean may get a jump-start from the other side of the world
 |
| Ocean waves crashing on beach. |
Think of it as ocean-to-ocean altruism in the age of climate change.
The new study, from Shineng Hu of the Scripps Institution of Oceanography at the University of California-San Diego and Alexey Fedorov of Yale University, appears Sept. 16 in the journal Nature Climate Change. It is the latest in a growing body of research that explores how global warming may alter global climate components such as the Atlantic meridional overturning circulation (AMOC).
AMOC is one of the planet's largest water circulation systems. It operates like a liquid escalator, delivering warm water to the North Atlantic via an upper limb and sending colder water south via a deeper limb.
Although AMOC has been stable for thousands of years, data from the past 15 years, as well as computer model projections, have given some scientists cause for concern. AMOC has showed signs of slowing during that period, but whether it is a result of global warming or only a short-term anomaly related to natural ocean variability is not known.
"There is no consensus yet," Fedorov said, "but I think the issue of AMOC stability should not be ignored. The mere possibility that the AMOC could collapse should be a strong reason for concern in an era when human activity is forcing significant changes to the Earth's systems.
"We know that the last time AMOC weakened substantially was 15,000 to 17,000 years ago, and it had global impacts," Fedorov added. "We would be talking about harsh winters in Europe, with more storms or a drier Sahel in Africa due to the downward shift of the tropical rain belt, for example."
Much of Fedorov and Hu's work focuses on specific climate mechanisms and features that may be shifting due to global warming. Using a combination of observational data and sophisticated computer modeling, they plot out what effects such shifts might have over time. For example, Fedorov has looked previously at the role melting Arctic sea ice might have on AMOC.
For the new study, they looked at warming in the Indian Ocean.
"The Indian Ocean is one of the fingerprints of global warming," said Hu, who is first author of the new work. "Warming of the Indian Ocean is considered one of the most robust aspects of global warming."
The researchers said their modeling indicates a series of cascading effects that stretch from the Indian Ocean all way over to the Atlantic: As the Indian Ocean warms faster and faster, it generates additional precipitation. This, in turn, draws more air from other parts of the world, including the Atlantic, to the Indian Ocean.
With so much precipitation in the Indian Ocean, there will be less precipitation in the Atlantic Ocean, the researchers said. Less precipitation will lead to higher salinity in the waters of the tropical portion of the Atlantic -- because there won't be as much rainwater to dilute it. This saltier water in the Atlantic, as it comes north via AMOC, will get cold much quicker than usual and sink faster.
"This would act as a jump-start for AMOC, intensifying the circulation," Fedorov said. "On the other hand, we don't know how long this enhanced Indian Ocean warming will continue. If other tropical oceans' warming, especially the Pacific, catches up with the Indian Ocean, the advantage for AMOC will stop."
Read more at Science Daily
US and Canada have lost more than 1 in 4 birds in the past 50 years
 |
| Three swallows on a branch. |
"Multiple, independent lines of evidence show a massive reduction in the abundance of birds," said Ken Rosenberg, the study's lead author and a senior scientist at the Cornell Lab of Ornithology and American Bird Conservancy. "We expected to see continuing declines of threatened species. But for the first time, the results also showed pervasive losses among common birds across all habitats, including backyard birds."
The study notes that birds are indicators of environmental health, signaling that natural systems across the U.S. and Canada are now being so severely impacted by human activities that they no longer support the same robust wildlife populations.
The findings showed that of nearly 3 billion birds lost, 90 percent belong to 12 bird families, including sparrows, warblers, finches, and swallows -- common, widespread species that play influential roles in food webs and ecosystem functioning, from seed dispersal to pest control.
Among the steep declines noted:
- Grassland birds are especially hard hit, with a 53 percent reduction in population -- more than 720 million birds -- since 1970.
- Shorebirds, most of which frequent sensitive coastal habitats, were already at dangerously low numbers and have lost more than one-third of their population.
- The volume of spring migration, measured by radar in the night skies, has dropped by 14 percent in just the past decade.
"These data are consistent with what we're seeing elsewhere with other taxa showing massive declines, including insects and amphibians," said coauthor Peter Marra, senior scientist emeritus and former head of the Smithsonian Migratory Bird Center and now director of the Georgetown Environment Initiative at Georgetown University. "It's imperative to address immediate and ongoing threats, both because the domino effects can lead to the decay of ecosystems that humans depend on for our own health and livelihoods -- and because people all over the world cherish birds in their own right. Can you imagine a world without birdsong?"
Evidence for the declines emerged from detection of migratory birds in the air from 143 NEXRAD weather radar stations across the continent in a period spanning over 10 years, as well as from nearly 50 years of data collected through multiple monitoring efforts on the ground.
"Citizen-science participants contributed critical scientific data to show the international scale of losses of birds," said coauthor John Sauer of the U.S. Geological Survey (USGS). "Our results also provide insights into actions we can take to reverse the declines." The analysis included citizen-science data from the North American Breeding Bird Survey coordinated by the USGS and the Canadian Wildlife Service -- the main sources of long-term, large-scale population data for North American birds -- the Audubon Christmas Bird Count, and Manomet's International Shorebird Survey.
Although the study did not analyze the causes of declines, it noted that the steep drop in North American birds parallels the losses of birds elsewhere in the world, suggesting multiple interacting causes that reduce breeding success and increase mortality. It noted that the largest factor driving these declines is likely the widespread loss and degradation of habitat, especially due to agricultural intensification and urbanization.
Other studies have documented mortality from predation by free-roaming domestic cats; collisions with glass, buildings, and other structures; and pervasive use of pesticides associated with widespread declines in insects, an essential food source for birds. Climate change is expected to compound these challenges by altering habitats and threatening plant communities that birds need to survive. More research is needed to pinpoint primary causes for declines in individual species.
"The story is not over," said coauthor Michael Parr, president of American Bird Conservancy. "There are so many ways to help save birds. Some require policy decisions such as strengthening the Migratory Bird Treaty Act. We can also work to ban harmful pesticides and properly fund effective bird conservation programs. Each of us can make a difference with everyday actions that together can save the lives of millions of birds -- actions like making windows safer for birds, keeping cats indoors, and protecting habitat."
The study also documents a few promising rebounds resulting from galvanized human efforts. Waterfowl (ducks, geese, and swans) have made a remarkable recovery over the past 50 years, made possible by investments in conservation by hunters and billions of dollars of government funding for wetland protection and restoration. Raptors such as the Bald Eagle have also made spectacular comebacks since the 1970s, after the harmful pesticide DDT was banned and recovery efforts through endangered species legislation in the U.S. and Canada provided critical protection.
"It's a wake-up call that we've lost more than a quarter of our birds in the U.S. and Canada," said coauthor Adam Smith from Environment and Climate Change Canada. "But the crisis reaches far beyond our individual borders. Many of the birds that breed in Canadian backyards migrate through or spend the winter in the U.S. and places farther south -- from Mexico and the Caribbean to Central and South America. What our birds need now is an historic, hemispheric effort that unites people and organizations with one common goal: bringing our birds back."
Organizations Behind the Study
American Bird Conservancy (ABC) is a nonprofit organization dedicated to conserving birds and their habitats throughout the Americas. With an emphasis on achieving results and working in partnership, we take on the greatest problems facing birds today, innovating and building on rapid advancements in science to halt extinctions, protect habitats, eliminate threats, and build capacity for bird conservation.
Bird Conservancy of the Rockies (Bird Conservancy) is a Colorado-based nonprofit that works to conserve birds and their habitats through an integrated approach of science, education, and land stewardship. Our work extends from the Rockies to the Great Plains, Mexico, and beyond. Together, we are improving native bird populations, the land, and the lives of people. Bird Conservancy's vision is a future where birds are forever abundant, contributing to healthy landscapes and inspiring human curiosity and love of nature.
The Cornell Lab of Ornithology is a nonprofit member-supported organization dedicated to interpreting and conserving the earth's biological diversity through research, education, and citizen science focused on birds.
Environment and Climate Change Canada is Canada's lead federal department for a wide range of environmental issues. It informs Canadians about protecting and conserving our natural heritage, and ensuring a clean, safe, and sustainable environment for present and future generations.
Advancing Georgetown's commitment to the environment, sustainability, and equitability, the Georgetown Environment Initiative brings together students, faculty, and staff from across disciplines -- from the natural sciences, social sciences, humanities, public policy, law, medicine, and business -- to contribute to global efforts to deepen understanding of our world and to transform the Earth's stewardship.
Read more at Science Daily
Subscribe to:
Posts (Atom)