Novel technique decodes mechanisms controlling executive functions of the primate brain

Researchers devise a new technique to identify specific neural pathways involved in executive functions of the brain

THE NATIONAL INSTITUTES FOR QUANTUM AND RADIOLOGICAL SCIENCE AND TECHNOLOGY

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IMAGE: IMAGE-GUIDED CHEMOGENETIC SYNAPTIC SILENCING CAN BE USED TO STUDY COGNITIVE FUNCTIONS. view more 

CREDIT: NATIONAL INSTITUTES FOR QUANTUM AND RADIOLOGICAL SCIENCE AND TECHNOLOGY

The human brain is a wonderfully enigmatic organ, helping to juggle multiple tasks efficiently to help us get through a long day! This feature, called executive function, seats primates like us at the pinnacle of evolution. The prospect of losing the spectacular flow of neural information in our brains because of an accident or disease is, thus, unnerving. In the event of such an unfortunate occurrence, to restore the brain to its previous working condition with full functionality--to reboot it, so to speak--would need a better understanding of the specific neural pathways involved in our daily activities that rely on working memory and decision-making--two important executive functions.

To achieve this objective, a group of researchers from National Institutes for Quantum and Radiological Science and Technology (QST), Japan, were hard at work at devising a technique they call "imaging-guided chemogenetic synaptic silencing" to decipher the specific neural pathways involved in high-order executive functions. In a pioneering study published in Science Advances, the researchers now report successfully delineating specific neural pathways involved in working memory and decision-making using this technique.

The group, led by eminent researcher Dr. Takafumi Minamimoto from the Department of Functional Brain Imaging, QST, focused on studying the dorsolateral part of the prefrontal cortex (dlPFC) in the monkey brain, to apply their novel technique, and further identify the neural pathways of interest. It is interesting to note this choice, not only because it is the brain region partially responsible for controlling executive functions, but also since this specialized region is only present in primates.

Importantly, the role of dlPFC is supported by brain regions like the dorsal caudate (dCD) and lateral mediodorsal thalamus (MDl) too. This intricate association is further explained by Dr. Kei Oyama, who is the first author of the study, as follows, "The primate prefrontal cortex (PFC), especially its dorsolateral part (dlPFC), is well known to serve as the center of higher-order executive functions; it is uniquely developed in primates and underlies their distinctive cognitive abilities. These functions, however, do not solely rely on dlPFC neurons but also on their cooperative interactions with subcortical structures, including the dorsal caudate (dCD) nucleus and lateral mediodorsal thalamus (MDl)."

Next, the researchers wanted to understand the who-does-what for working memory and decision-making. Given that the dlPFC, MDI, and dCD neurons are connected, they selectively silenced specific neuronal synapses to disrupt the flow of information, and achieve just dlPFC-dCD and dlPFC-MDl projections, either unilaterally (involving just one side of the brain), or bilaterally (involving both sides). To achieve this, they made the dlPFC neurons express designer receptors exclusively activated by designer drugs (DREADDs). Further, the monkeys involved in the study were analyzed for behavioral changes, to understand the effect of chemogenetic silencing.

Interestingly, the researchers observed that silencing the bilateral dlPFC-MDl projections in the monkeys, but not their dlPFC-dCD projections, caused problems in the working memory related to their surroundings. On the contrary, silencing their unilateral dlPFC-dCD projections, but not their unilateral dlPFC-MDl projections, altered their preference in decision-making. These results reveal that the two higher-brain functions, working memory and decision-making, which are essential for our daily lives, are controlled by different neural pathways linking specific brain areas.

Overall, this study lays the foundation for further explorations of the intricacies of the complex primate brain. In this regard, Dr. Oyama explains the potential clinical and research applications of these findings, "Many psychiatric disorders, including depression, are thought to be associated with disturbances in the transmission of neural information through neural circuits between specific brain regions. Our findings are expected to deepen our understanding of mental disorders and lead to the discovery of treatments and remedies. The successful development of a novel technique in our study will serve as a key technology for the next-generation of researchers to investigate primate brain functions, which will contribute to broad areas in life by dramatically deepening our understanding of the mechanism of higher-brain functions."

The world will indeed wait with bated breath for future mysteries to unravel as explorations take researchers deeper into the labyrinthine maze that is the mind.

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Research Article:
"Chemogenetic dissection of the primate prefronto-subcortical pathways for working memory and decision-making"
Kei Oyama, Yukiko Hori, Yuji Nagai, Naohisa Miyakawa, Koki Mimura, Toshiyuki Hirabayashi, Ken-ichi Inoue, Tetsuya Suhara, Masahiko Takada, Makoto Higuchi and Takafumi Minamimoto
Science Advances: June 23, 2021, DOI: https://doi.org/10.1126/sciadv.abg4246

About National Institutes for Quantum and Radiological Science and Technology:

The National Institutes for Quantum and Radiological Science and Technology (QST) was established in April 2016 to promote quantum science and technology in a comprehensive and integrated manner. QST's mission is to raise the level of quantum and radiological sciences and technologies through its commitment to research and development into quantum science and technology, the effect of radiation on humans, radiation emergency medicine, and the medical use of radiation. To ensure that research and development delivers significant academic, social and economic impacts, and to maximize benefits from global innovation, QST is striving to establish world-leading research and development platforms and explore new fields.

Website: https://www.qst.go.jp/site/qst-english/

About Dr. Kei Oyama from National Institutes for Quantum and Radiological Science and Technology, Japan:

Dr. Kei Oyama is a reputed researcher at the Department of Functional Brain Imaging. Specifically, Dr. Oyama is an active member of the Neural Systems and Circuits Research Group. He is an expert in different facets of behavioral and cognitive neuroscience, like learning and memory, behavior analyses, neuropharmacology, electrophysiology etc. His expertise is bolstered by around 20 publications in these fields, in reputed journals.

Funding information:

This study was funded by MEXT/JSPS KAKENHI grant numbers JP18K15353 and JP21K07268, JP17H02219, JP19H05467, JP15H05917 and JP18H04037, JP18H05018, and JP19K07811; QST President's Strategic Grant (Creative Research); AMED grant numbers JP20dm0307007, JP20dm0307021, JP18dm0207003, and JP20dm0107146; JST PRESTO grant number JPMJPR1683; cooperative research program at PRI, Kyoto University; and National Bio-Resource Project "Japanese Monkeys" of MEXT, Japan

 

Last ice-covered parts of summertime Arctic Ocean vulnerable to climate change

UNIVERSITY OF WASHINGTON

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IMAGE: THE STUDY LOOKED AT THE WANDEL SEA NORTH OF GREENLAND, WHICH IS INSIDE WHAT'S KNOWN AS THE "LAST ICE AREA " OF THE ARCTIC OCEAN. view more 

CREDIT: SCHWEIGER ET AL./COMMUNICATIONS EARTH & ENVIRONMENT

In a rapidly changing Arctic, one area might serve as a refuge - a place that could continue to harbor ice-dependent species when conditions in nearby areas become inhospitable. This region north of Greenland and the islands of the Canadian Arctic Archipelago has been termed the Last Ice Area. But research led by the University of Washington suggests that parts of this area are already showing a decline in summer sea ice.

Last August, sea ice north of Greenland showed its vulnerability to the long-term effects of climate change, according to a study published July 1 in the open-access journal Communications Earth & Environment.

"Current thinking is that this area may be the last refuge for ice-dependent species. So if, as our study shows, it may be more vulnerable to climate change than people have been assuming, that's important," said lead author Axel Schweiger, a polar scientist at the UW Applied Physics Laboratory.

How the last ice-covered regions will fare matters for polar bears that use the ice to hunt for seals that use the ice for building dens for their young, and for walruses that use the ice as a platform for foraging.

"This area has long been expected to be the primary refuge for ice-dependent species because it is one of the last places where we expect summer sea ice to survive in the Arctic," said co-author Kristin Laidre, a principal scientist at the UW Applied Physics Laboratory.

The study focused on sea ice in August 2020 in the Wandel Sea, an area that used to be covered year-round in thick, multi-year ice.

"Sea ice circulates through the Arctic, it has a particular pattern, and it naturally ends up piling up against Greenland and the northern Canadian coast," Schweiger said. "In climate models, when you spin them forward over the coming century, that area has the tendency to have ice survive in the summer the longest."

Like other parts of the Arctic Ocean, the ice here has been gradually thinning, though last spring's sea ice in the Wandel Sea was on average slightly thicker than previous years. But satellite images showed a record low of just 50% sea ice concentration on Aug. 14, 2020.

The new study uses satellite data and sea ice models to determine what caused last summer's record low. It finds that about 80% was due to weather-related factors, like winds that break up and move the ice around. The other 20%, or one-fifth, was from the longer-term thinning of the sea ice due to global warming.

The model simulated the period from June 1 to Aug. 16 and found that unusual winds moved sea ice out of the area, but that the multiyear thinning trend also contributed, by allowing more sunlight to warm the ocean. Then, when winds picked up, this warm water was able to melt the nearby ice floes.

The record-low ice concentration in 2020 was surprising because the average ice thickness at the beginning of summer was actually close to normal.

"During the winter and spring of 2020 you had patches of older, thicker ice that had drifted into there, but there was enough thinner, newer ice that melted to expose open ocean," Schweiger said. "That began a cycle of absorbing heat energy to melt more ice, in spite of the fact that there was some thick ice. So in years where you replenish the ice cover in this region with older and thicker ice, that doesn't seem to help as much as you might expect."

The results raise concerns about the Last Ice Area but can't immediately be applied to the entire region, Schweiger said. Also unknown is how more open water in this region would affect ice-dependent species over the short and long terms.

"We know very little about marine mammals in the Last Ice Area," said Laidre, who is also an associate professor in the School of Aquatic and Fishery Sciences. "We have almost no historical or present-day data, and the reality is that there are a lot more questions than answers about the future of these populations."

CAPTION

This photo of sea ice on the Wandel Sea north of Greenland was taken Aug. 16, 2020, from the German icebreaker Polarstern, which passed through the area as part of the year-long MOSAiC Expedition. This area used to remain fully covered in ice throughout the year. Satellite images show that Aug. 14, 2020, was a record low sea ice concentration for this region, at 50%.

CREDIT

Felix Linhardt/Kiel University

Other co-authors are Michael Steele and Jinlun Zhang at the UW; and Kent Moore at the University of Toronto. The research was funded by the U.S. National Science Foundation, NASA, the Natural Sciences and Engineering Research Council of Canada; the National Oceanic and Atmospheric Administration; the Office of Naval Research; and the World Wildlife Fund Canada.

CAPTION

A polar bear is perched on a thick chunk of sea ice north of Greenland in March 2016. These thicker, older pieces of sea ice don't fully protect the larger region from losing its summer ice cover.

CREDIT

Kristin Laidre/University of Washington

 

Fecal records show Maya population affected by climate change

Findings suggest that Maya settlement in city of Itzan started earlier and lasted longer than previously known

MCGILL UNIVERSITY

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IMAGE: FECAL RECORDS FROM LAKE SEDIMENT SHOW THAT MAYA LIVED IN THE AREA FOR LONGER THAN PREVIOUSLY BELIEVED. view more 

CREDIT: ANDY BRECKENRIDGE

A McGill-led study has shown that the size of the Maya population in the lowland city of Itzan (in present-day Guatemala) varied over time in response to climate change. The findings, published recently in Quaternary Science Reviews, show that both droughts and very wet periods led to important population declines.

These results are based on using a relatively new technique involving looking at stanols (organic molecules found in human and animal faecal matter) taken from the bottom of a nearby lake. Measurements of stanols were used to estimate changes in population size and to examine how they align with information about climate variability and changes in vegetation drawn from other biological and archaeological sources.

By using the technique, the researchers were able to chart major Maya population changes in the area over a period starting 3,300 years before the present (BP). They were also able to identify shifts in settlement patterns that took place over the course of hundreds of years that are associated with changes in land use and agricultural practices.

They discovered, moreover, that the land had been settled earlier than previously suggested by archaeological evidence.

New tool provides surprising information about human presence in Maya lowlands

The evidence from faecal stanols suggests that humans were present on the Itzan escarpment about 650 years before the archaeological evidence confirms it. It also shows that that the Maya continued to occupy the area, albeit in smaller number, after the so-called "collapse" between 800-1000 AD, when it had previously been believed that drought or warfare caused the entire population to desert the area. There is further evidence of a large population spike around the same time as a historical record of refugees fleeing the Spanish attack of 1697 AD on the last Maya stronghold in the southern Maya lowlands (Nojpeten, or modern-day Flores in Guatemala) - something that had not been known before.

Estimates of ancient population size in the Maya lowlands have traditionally been obtained through ground inspection and excavation. To reconstruct population dynamics, archaeologists locate, map, and count residential structures, and they excavate them to establish dates of occupation. They compare population trends at the site and regional levels. And they then use techniques such as pollen analysis and indicators of soil erosion into lakes to reconstruct the ecological changes that took place at the same time.

"This research should help archaeologists by providing a new tool to look at changes that might not be seen in the archaeological evidence, because the evidence may never have existed or may have since been lost or destroyed," said Benjamin Keenan, a PhD candidate in the Department of Earth and Planetary Sciences at McGill, and the first author on the paper. "The Maya lowlands are not very good for preserving buildings and other records of human life because of the tropical forest environment."

CAPTION

Diagram showing how fecal stanol molecules are transported from human intestines to lake sediments, where they are then recovered in sediment cores.

CREDIT

Benjamin Keenan et al.

Maya population size affected by both droughts and wet periods

The faecal stanol from the sediment in Laguna Itzan confirms that the Maya population in the area declined due to drought at three different periods; between 90-280 AD, between 730-900 AD and during the much less well studied drought between 1350-950 BC. The researchers also found that the population declined during a very wet period from 400--210 BC, something which has received little attention until now. The population decline in response to both dry and wet periods shows that there were climatic effects on population at both climate extremes, and not only during dry periods.

"It is important for society generally to know that there were civilisations before us that were affected by and adapted to climate change," said Peter Douglas, an assistant professor in the Department of Earth and Planetary Sciences and the senior author on the paper. "By linking evidence for climate and population change we can begin to see a clear link between precipitation and the ability of these ancient cities to sustain their population."

The research also suggests that the Maya people may have adapted to environmental issues such as soil degradation and nutrient loss by using techniques such as the application of human waste (also known as night soil) as a fertiliser for crops. This is suggested by a relatively low amount of fecal stanols in the lake sediment at a time when there is archaeological evidence for the highest human populations. One explanation for this is that human waste was applied to soils as fertilizer and therefore the stanols were not washed into the lake.

CAPTION

Benjamin Keenan, the lead researcher, collecting a lake sediment core on Lake Izabal, the largest lake in Guatemala.

CREDIT

Elisandra Hernández

About this study

"Molecular evidence for human population change associated with climate events in the Maya lowlands" by Benjamin Keenan et al. was published in Quaternary Science Reviews. The research was funded by the Eric Mountjoy Fellowship, McGill startup funds, and an NSERC Discovery Grant.

DOI: https://doi.org/10.1016/j.quascirev.2021.106904

About McGill University

Founded in Montreal, Quebec, in 1821, McGill University is Canada's top ranked medical doctoral university. McGill is consistently ranked as one of the top universities, both nationally and internationally. It?is a world-renowned?institution of higher learning with research activities spanning two campuses, 11 faculties, 13 professional schools, 300 programs of study and over 40,000 students, including more than 10,200 graduate students. McGill attracts students from over 150 countries around the world, its 12,800 international students making up 31% of the student body. Over half of McGill students claim a first language other than English, including approximately 19% of our students who say French is their mother tongue.

https://www.mcgill.ca/newsroom/

 

UMaine-led study: Imaging spectroscopy can predict water stress in wild blueberry fields

UNIVERSITY OF MAINE

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Imaging spectroscopy can help predict water stress in wild blueberry barrens, according to a University of Maine-led study.

The technology involves measuring the light reflected off of objects depicted in images captured by drones, satellites and other remote sensing technology to classify and gather pertinent information about the objects. According to researchers, it can precisely measure light across dozens, if not hundreds, of bands of colors. The reflectance spectra can depict nutrient levels, chlorophyll content and other indicators of health for various crops, according to researchers.

Scientists from UMaine, the Schoodic Institute and Wyman's, one of the world's largest purveyors of wild blueberries and the number one brand of frozen fruit in the country, found in their research that when incorporated into models, imaging spectroscopy can help predict whether wild blueberry fields will lack sufficient water for growing. Not only can the technology help inform growers as they evaluate irrigation routines and manage their water resources in a way that avoids damaging the crop, researchers say.

The team collected imaging spectroscopy data by deploying a drone equipped with a spectrometer for capturing visible and near-infrared light to photograph wild blueberry fields owned by Wyman's in Debois, Maine. Researchers then processed the images to measure reflected light spectra from the plants for indications of chlorophyll levels and other properties that would help estimate their water potential, which, they say, is the primary force driving water flow and an indicator of water stress. At the same time, the group collected small branches with leaves from wild blueberry plants in the plots to assess their water potential and validate the spectra-based estimation. Pictures and samples were collected in the spring and summer of 2019 when the plants experienced peak bloom, green fruit and color break.

The data from both drone images and ground samples were incorporated into models, which they developed using machine learning and statistical analysis, to estimate water potential, and thereby predict water stress, of the plants in the barrens. Models from the ground sample data were used to help guide the development of and validate the model created with data from the images. The results of both sets of models were comparable, demonstrating that imaging spectroscopy can accurately predict water stress in wild blueberry barrens at different times of the growing season. With the efficacy of the technology confirmed, researchers say scientists can capitalize on the benefits of it, such as conducting repeated measurements on small objects like blueberry leaves with ease.

Graduate student Catherine Chan led the study, joined by UMaine faculty Daniel Hayes and Yongjiang Zhang, Schoodic Institute forest ecologist Peter Nelson and Wyman's agronomist Bruce Hall. The journal Remote Sensing published a report of their findings.

"We couple spectral data and areas of known water potential in wild blueberry fields through machine learning, creating a model to further predict areas that may be water stressed," Chan says.

Understanding how to sustainably manage water resources to mitigate risk associated with current and increasing drought frequency is crucial to wild blueberry growers, researchers say.

"This research provides key learnings to ensure the continued viability of wild blueberry crops for generations to come," Hall says.

Warming and drought exacerbated by climate change have compounded their struggles in recent years, alongside freezing and pathogens. Researchers say as a result, there has been an increased need for predictive tools, like imaging spectroscopy and models that rely on it, for land conditions to inform mitigation strategies.

Nelson says the study was conducted in cooperation with his laboratory of ecological spectroscopy (lecospec) at the Schoodic Institute, which was financed by the Maine Economic Improvement Fund, Maine Space Grant Consortium, the National Aeronautics and Space Administration (NASA) and other University of Maine System funds. The research team used a software he developed with Chan and other students that allows drones and spectrometers to measure light across dozens or hundreds of more bands of color than an average camera, Nelson says.

"We envisioned and continue to promote this as a research and application tool to produce data and algorithms applied to questions and problems in forest, agricultural and marine sectors of Maine's economy," he says.

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Cleaner air has boosted US corn and soybean yields, Stanford-led research shows

STANFORD UNIVERSITY

Research News

 

IMAGE: SOY BEANS IN A FIELD READY FOR HARVEST IN FENTON, ILLINOIS. view more 

CREDIT: KELLY SIKKEMA / UNSPLASH

A key factor in America's prodigious agricultural output turns out to be something farmers can do little to control: clean air. A new Stanford-led study estimates pollution reductions between 1999 and 2019 contributed to about 20 percent of the increase in corn and soybean yield gains during that period - an amount worth about $5 billion per year.

The analysis, published this week in Environmental Research Letters, reveals that four key air pollutants are particularly damaging to crops, and accounted for an average loss of about 5 percent of corn and soybean production over the study period. The findings could help inform technology and policy changes to benefit American agriculture, and underscore the value of reducing air pollution in other parts of the world.

"Air pollution impacts have been hard to measure in the past, because two farmers even just 10 miles apart can be facing very different air quality. By using satellites, we were able to measure very fine scale patterns and unpack the role of different pollutants," said study lead author David Lobell, the Gloria and Richard Kushel Director of the Center on Food Security and the Environment.

The research highlights the considerable power of satellites to illuminate pollution impacts at a scale not possible otherwise. That power could be of even greater value in countries with less access to air monitors and yield data.

Reading the air

Scientists have long known that air pollution is toxic to plant life in high doses, but not how much farmers' yields are actually hurt at current levels. The impact of pollution on agriculture overall, as well as the effects of individual pollutants, has also remained unknown.

Focusing on a nine-state region (Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, South Dakota and Wisconsin) that produces roughly two-thirds of national maize and soybean output, Lobell and study co-author Jennifer Burney, an associate professor of environmental science at the University of California, San Diego, set out to measure the impact on crop yields of ozone, particulate matter, nitrogen dioxide and sulfur dioxide.

Ozone is the result of heat and sunlight-driven chemical reactions between nitrogen and hydrocarbons, such as those found in car exhaust. Particulate matter refers to large particles of dust, dirt, soot or smoke. Nitrogen dioxide and sulfur dioxide are gases released into the atmosphere primarily through the burning of fossil fuels at power plants and other industrial facilities.

"This has been a tricky problem to untangle because historically our measurements of different types of air pollutants and our measurements of agricultural yields haven't really overlapped spatially at the necessary resolution," explained Burney. "With the new high spatial resolution data, we could look at crop yields near both pollution monitors and known pollutant emissions sources. That revealed evidence of different magnitudes of negative impacts caused by different pollutants."

Lobell and Burney extended their analysis back to 1990, when Congress passed Clean Air Act amendments that resulted in significant air quality improvements across the country. The researchers looked through air pollution data from hundreds of monitoring stations around the region, federal data on power plant emissions, satellite-based observations of nitrogen dioxide around those power plants, crop yield data from federal surveys and satellite imagery, as well as weather data to account for growing season conditions known to explain crop yield variations.

Surprising findings

What Lobell and Burney discovered surprised them. Among their findings: negative effects of each of the four pollutants on corn and soybean yields, and a clear yield increase the farther away from power plants - particularly coal-burning facilities - crops were grown. The unique spatial patterns of each pollutant allowed them to disentangle the effect of each pollutant in a way that past studies could not.

The researchers estimated that total yield losses from the four pollutants averaged 5.8 percent for maize and 3.8 percent for soybean over the past two decades. Those losses declined over time as the air grew cleaner. In fact, the reduction in air pollution contributed to an estimated 4 percent growth in corn yields and 3 percent growth in soybean yields - increases that equal 19 percent of corn's overall yield gains during the timeframe and 23 percent of soybeans' overall yield gains.

"We already know that the Clean Air Act resulted in trillions of dollars of benefits in terms of human health, so I think of these billions in agricultural benefits as icing on the cake," Lobell said. "But even if it's a small part of the benefits of clear air, it has been a pretty big part of our ability to continue pushing agricultural productivity higher."

CAPTION

A farmer plants soybeans using a no-till planter in Vincennes, Indiana.

CREDIT

Brandon O'Connor / Natural Resources Conservation Service

Lobell is also a professor of Earth system science in Stanford's School of Earth, Energy & Environmental Sciences, the William Wrigley Senior Fellow at the Stanford Woods Institute for the Environment and a senior fellow at the Freeman Spogli Institute for International Studies and the Stanford Institute for Economic Policy Research. Burney also holds the Marshall Saunders Chancellor's Endowed Chair in Global Climate Policy and Research at UC San Diego and is a research affiliate at UC San Diego's Policy Design and Evaluation Laboratory, a fellow at the Stanford Center on Food Security and the Environment, and head of the Science Policy Fellows Program at UC San Diego.

This research was funded by NASA and the National Science Foundation.

 

Better predicting how plants and animals will weather climate extremes

Leading scientists argue the need to consider biomechanics

UNIVERSITY OF CALIFORNIA - RIVERSIDE

Research News

 

IMAGE: TREES AND OTHER ORGANISMS FACING AIR OR WATER FLOW WILL EXPERIENCE FORCES THAT COULD BEND, BREAK, OR DISLODGE THEM. BY UNDERSTANDING THE VARIABLES THAT HELP RESIST THOSE FORCES, AS WELL... view more 

CREDIT: (TIM HIGHAM/UCR)

A team of scientists has devised a more accurate way to predict the effects of climate change on plants and animals -- and whether some will survive at all.

Frequently, ecologists assess an organism's fitness relative to the climate by quantifying its functional traits.

"These are physical properties you can measure -- height, diameter, the thickness of a tree," said UC Riverside biologist Tim Higham. "We believe more information is needed to understand how living things will respond to a changing world."

The team, led by Higham, outlines an alternative model for researchers in an article published today in the journal Trends in Ecology and Evolution.

This new model incorporates the functional traits of an organism as well as environmental variables, such as temperature, habitat structure, and the speed of wind or water an organism interacts with. The team calls these "ecomechanical models."

As oceans rise, strong storms will reach farther inland. The intensity of hurricanes, and the proportion of hurricanes that reach very intense levels, will likely increase with climate change. As a result, Higham said that fluids will exert greater forces on anything in their path. These forces could cause organisms with roots, such as trees, to break or be uprooted.

"If you measure the functional traits of a tree, and we know the speed of the wind, we can predict how much bending will occur," Higham said. "At certain wind speeds, the tree will potentially come down."

The way wind disperses seeds, or how insects and birds fly in the face of strong winds, can potentially influence their fitness. When considering the fate of living things, the physics governing the way they move through space is another important factor accounted for by this new framework. In this sense, ecomechanical models are not limited to understanding the impacts of climate change.

"They can help scientists understand evolutionary patterns and how animals interact differently with their environment as they grow," Higham said.

Environmental conditions can affect how some animals attach to surfaces. For example, geckos can use their famous adhesive system to attach to smooth surfaces. However, the real-world is not often smooth. Therefore, understanding how geckos attach requires knowledge of both the animal's functional traits and the environment's texture, for example.

In order to facilitate use of this model by many different types of scientists, the research team urges the expansion of freely available online databases in which functional traits of organisms have been described in a uniform, standardized way.

This work was years in the making, the product of a working group funded by the National Science Foundation. The group is composed of 24 scientists from Arizona State University; Claremont Colleges; University of British Columbia; University of Illinois, Clark University; the University of Calgary, The State University of Northern Rio de Janeiro, Brazil; Rutgers University; University of Waterloo in Ontario, Canada; University of Washington; George Washington University; Trinity University; UC Berkeley; Cornell University; Towson University, and the American Museum of Natural History.

Many of the participating faculty identify as members of underrepresented groups in science. "Including faculty in early career stages, and from a diversity of backgrounds and lived experiences was of paramount importance to us as we created the working group," said Lara Ferry, biologist and President's Professor from Arizona State University. "We know the best results come from the collective contributions of many different perspectives."

Should these recommendations become widely adopted, the research team feels there will be profound impacts on multiple areas of biology.

"The use of ecomechanical models can help us understand the rules of life," Higham said.

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Microbes in cow stomachs can break down plastic

Bacteria found in the rumen, one of the compartments that make up the cow stomach, can break down plastics, representing an eco-friendly way to reduce litter

FRONTIERS

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Plastic is notoriously hard to break down, but researchers in Austria have found that bacteria from a cow's rumen - one of the four compartments of its stomach - can digest certain types of the ubiquitous material, representing a sustainable way to reduce plastic litter.

The scientists suspected such bacteria might be useful since cow diets already contain natural plant polyesters. "A huge microbial community lives in the rumen reticulum and is responsible for the digestion of food in the animals," said Dr Doris Ribitsch, of the University of Natural Resources and Life Sciences in Vienna, "so we suspected that some biological activities could also be used for polyester hydrolysis," a type of chemical reaction that results in decomposition. In other words, these microorganisms can already break down similar materials, so the study authors thought they might be able to break down plastics as well.

Ribitsch and her colleagues looked at three kinds of polyesters. One, polyethylene terephthalate, commonly known as PET, is a synthetic polymer commonly used in textiles and packaging. The other two consisted of a biodegradable plastic often used in compostable plastic bags (polybutylene adipate terephthalate, PBAT), and a biobased material (Polyethylene furanoate, PEF) made from renewable resources.

They obtained rumen liquid from a slaughterhouse in Austria to get the microorganisms they were testing. They then incubated that liquid with the three types of plastics they were testing (which were tested in both powder and film form) in order to understand how effectively the plastic would break down.

According to their results, which were recently published in Frontiers in Bioengineering and Biotechnology, all three plastics could be broken down by the microorganisms from cow stomachs, with the plastic powders breaking down quicker than plastic film. Compared to similar research that has been done on investigating single microorganisms, Ribitsch and her colleagues found that the rumen liquid was more effective, which might indicate that its microbial community could have a synergistic advantage - that the combination of enzymes, rather than any one particular enzyme, is what makes the difference.

While their work has only been done at a lab scale, Ribitsch says, "Due to the large amount of rumen that accumulates every day in slaughterhouses, upscaling would be easy to imagine." However, she cautions that such research can be cost-prohibitive, as the lab equipment is expensive, and such studies require pre-studies to examine microorganisms.

Nevertheless, Ribitsch is looking forward to further research on the topic, saying that microbial communities have been underexplored as a potential eco-friendly resource.

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