Adult coral can handle more heat and keep growing thanks to heat-evolved symbionts

 Adult fragments of a coral species can better tolerate bleaching and recover faster when treated with tougher heat-evolved symbionts, new research from the Australian Institute of Marine Science (AIMS) and the University of Melbourne indicates.

The study also found that treatment with the heat-evolved symbionts did not compromise the coral's ability to grow. This differs from previous studies on Great Barrier Reef corals which found that naturally heat tolerant symbionts could enhance heat resistance in adult corals, but at a cost to its growth.

Symbionts are the tiny cells of algae that live inside the coral tissue, providing corals with energy to grow. The survival of reef-building corals depends on this mutually beneficial relationship.

The symbionts used in this study had their heat tolerance bolstered in the lab by exposing multiple generations to elevated temperatures for 10 years. Adult coral fragments of a single species, Galaxea fascicularsis, that had been chemically bleached were then offered the heat-evolved symbionts. The scientists found the symbionts were able to maintain a symbiosis with adult corals for two years, promoting faster coral recovery from bleaching and enhancing their heat tolerance without trading off on growth.

Lead author on the study Dr Wing Yan Chan from AIMS and the University of Melbourne said the new findings suggest that heat-evolved algal symbionts are a potentially valuable resource for reef restoration applicable across coral species and life stages.

"These symbionts were still detected in the corals in moderate abundance two years after the corals were first inoculated, suggesting long-term stability of this symbiosis and potential long-term benefits to coral heat tolerance," she said.

"Strategies to enhance coral heat tolerance can buy time for reefs, which are threatened by climate change-driven marine heatwaves causing bleaching and sometimes mortality. The long-term stability of the symbiosis offers hope they may be able to provide benefits to their coral hosts for many years."

Professor Madeleine van Oppen from AIMS and the University of Melbourne, who is the senior author on the research, said earlier work in her group had shown the benefits of associating heat-evolved symbionts with coral larvae and juveniles.

"These new findings on adult coral close the circle and demonstrate the advantages are not lost in adulthood," she said.

"This approach is one of several referred to as 'assisted evolution', which involves active interventions to accelerate the rate of naturally occurring evolutionary processes."

Dr Chan said the next critical step of this research will be controlled field trials before it could be determined whether the intervention could work outside of the laboratory, with more than one coral type and at scale.

Dr Line Bay, a Research Program Director from AIMS who oversees AIMS' coral focussed work within the Reef Restoration and Adaptation Program (RRAP), said the work was an important step in the research on enhancing heat tolerance in corals.

"This study is part of the extensive work AIMS, our partners and collaborators are doing to protect corals from climate change," she said.

"To give coral reefs the best chance of survival, we need to reduce emissions, ensure coral reef systems are managed well, and develop interventions like heat-evolved symbionts to help boost climate tolerance and resilience for reefs."

The research was a collaboration between AIMS, the University of Melbourne, Monash Institute of Pharmaceutical Sciences and the Melbourne Centre for Nanofabrication.

The research was funded by the Australian Research Council, the Paul G. Allen Family Foundation and RRAP, which is funded by a partnership between the Australian Government's Reef Trust and the Great Barrier Reef Foundation.

Research connecting gut bacteria and oxytocin provides a new mechanism for microbiome-promoted health benefits

 The gut microbiome, a community of trillions of microbes living in the human intestines, has an increasing reputation for affecting not only gut health but also the health of organs distant from the gut. For most microbes in the intestine, the details of how they can affect other organs remain unclear, but for gut resident bacteria L. reuteri the pieces of the puzzle are beginning to fall into place.

"L. reuteri is one of such bacteria that can affect more than one organ in the body," said co-corresponding author Dr. Sara Di Rienzi, assistant professor of molecular virology and microbiology at Baylor. "Researchers have found that these bacteria reduce gut inflammation in adults and rodent models, suppress bone loss in animal models of osteoporosis and in a human clinical trial, promote skin wound healing in mice and humans and improve social behavior in six mouse models of autism spectrum disorder."

Of those effects of L. reuteri, the abilities to promote social behavior and wound healing have been shown to require signaling by the hormone oxytocin, but little was known about how this occurs.

"We investigated the link connecting L. reuteri, oxytocin and distant organs such as the brain and uncovered unexpected findings," said first author Dr. Heather Danhof, assistant professor of molecular virology and microbiology at Baylor. "Oxytocin is mostly produced in the hypothalamus, a brain region involved in regulating feeding and social behavior, as well as in other organs. Given that other brain-produced hormones also are made in the gut, we tested the novel idea that oxytocin itself was also produced in the intestinal epithelium where L. reuteri typically resides."

The researchers built up their case step by step. First, they reviewed single-cell RNA-Seq datasets of the intestinal epithelium, which show which genes are expressed in that tissue. They found that oxytocin genes are expressed in the epithelium of various species, including mice, macaques and humans. Then, using fluorescence microscopy, the team revealed the presence of oxytocin directly on human intestinal organoids, also called mini guts, which are laboratory models of intestinal tissue that recapitulate many of its functions and structure.

"Finally, a big moment was when we visualized oxytocin in human intestinal tissue samples, demonstrating oxytocin as an intestinal hormone," Di Rienzi said.

"We also determined a mechanism by which L. reuteri mediates oxytocin secretion from human intestinal tissue and human intestinal organoids," Danhof said. "L. reuteri stimulates enteroendocrine cells in the intestine to release the gut hormone secretin, which in turn stimulates another intestinal cell type, the enterocyte, to release oxytocin."

"We are excited about these findings," said co-corresponding author Dr. Robert Britton, professor of molecular virology and microbiology and member of the Dan L Duncan Comprehensive Cancer Center at Baylor. "These bacteria have positive effects in various parts of the body, but it was not understood how that happened. Our findings reveal that oxytocin is also produced in the gut and a new mechanism by which L. reuteri affects oxytocin secretion. Now, we are working to identify potential treatments for autism spectrum disorders using a new mouse model deficient in intestinal oxytocin to gain a new understanding of the connection between oxytocin produced in the gut, social behavior and the brain."

New antibiotic approach proves promising against lyme bacterium

 Using a technique that has shown promise in targeting cancer tumors, a Duke Health team has found a way to deploy a molecular warhead that can annihilate the bacterium that causes Lyme disease.

Tested in cell cultures using the Borrelia burgdoferi bacterium, the approach holds the potential to target not only bacteria, but also fungi such as yeast and viruses. The findings appear in the journal Cell Chemical Biology.

"This transport mechanism gets internalized in the bacterium and brings in a molecule that causes what we've described as a berserker reaction -- a programmed death response," said lead author Timothy Haystead, Ph.D., professor in Duke's Department of Pharmacology and Cancer Biology. "It wipes out the bacteria -- sterilizes the culture with a single dose of light. And then when you look at what occurs with electron microscopy, you see the collapse of the chromosome."

Haystead and colleagues used a molecular facilitator called high-temperature protein G (HtpG), which is involved in protecting cells that are undergoing heat stress. This family of proteins has been the focus of drug development programs for possible cancer therapies.

Studies of this protein as an antimicrobial have also been encouraging, but the Duke team's work appears to be the first to tether an HtpG inhibitor to a drug that enhances sensitivity to light.

The researchers found that the HtpG inhibitor, armed with the photosensitive drug, was rapidly absorbed into the cells of the Lyme bacteria. When hit with light, the bacteria's cells went into disarray and ultimately collapsed, killing them.

"Our findings point to a new, alternate antibiotic development strategy, whereby one

can exploit a potentially vast number of previously unexplored druggable areas within bacteria to deliver cellular toxins," Haystead said.

In addition to Haystead, study authors include Dave L. Carlson, Mark Kowalewski, Khaldon Bodoor, Adam D. Lietzan, Philip Hughes, David Gooden, David L. Loiselle, David Alcorta, Zoey Dingman, Elizabeth A. Mueller, Irnov Irnov, Shannon Modla, Tim Chaya, Jeffrey Caplan, Monica Embers, Jennifer C. Miller, Christine Jacobs-Wagner, Matthew R. Redinbo, and Neil Spector (deceased).

The study received funding support from the Steven and Alexander Cohen foundation and Bay Area Lyme Foundation.

Biodiversity time machine' provides insights into a century of loss

 Scientists have run the first proof of concept of their DNA 'time machine' to shed light on a century of environmental change in a freshwater lake -- including warming temperatures and pollution, leading to the potentially irreversible loss of biodiversity.

Their approach, which uses AI applied to DNA-based biodiversity, climate variables and pollution, could help regulators to protect the planet's existing biodiversity levels, or even improve them.

Researchers from the University of Birmingham, in collaboration with Goethe University in Frankfurt, used sediment from the bottom of a lake in Denmark to reconstruct a 100-year-old library of biodiversity, chemical pollution, and climate change levels. This lake has a history of well-documented shifts in water quality, making it a perfect natural experiment for testing the biodiversity time machine.

Publishing their findings today (7 Nov) in eLife, the experts reveal that the sediment holds a continuous record of biological and environmental signals that have changed over time -- from (semi)pristine environments at the start of the industrial revolution to the present.

The team used environmental DNA -- genetic material left behind by plants, animals, and bacteria -- to build a picture of the entire freshwater community. Assisted by AI, they analysed the information, in conjunction with climate and pollution data, to identify what could explain the historic loss of species that lived in the lake.

Principal investigator Luisa Orsini, Professor of Evolutionary Systems Biology and Environmental Omics at the University of Birmingham and Fellow of the Alan Turing Institute, explained: "We took a sediment core from the bottom of the lake and used biological data within that sediment like a time machine -- looking back in time to build a detailed picture of biodiversity over the last century at yearly resolution. By analysing biological data with climate change data and pollution levels we can identify the factors having the biggest impact on biodiversity.

"Protecting every species without impacting human production is unrealistic, but using AI we can prioritise the conservation of species that deliver ecosystem services. At the same time, we can identify the top pollutants, guiding regulation of chemical compounds with the most adverse effect. These actions can help us not only to preserve the biodiversity we have today, but potentially to improve biodiversity recovery. Biodiversity sustains many ecosystem services that we all benefit from. Protecting biodiversity mean protecting these services."

The researchers found that pollutants such as insecticides and fungicides, alongside increases in minimum temperature (a 1.2-1.5-degree increase) caused the most damage to biodiversity levels.

However, the DNA present in the sediment also showed that over the last 20 years the lake had begun to recover. Water quality improved as agricultural land use declined in the area surrounding the lake. Yet, whereas the overall biodiversity increased, the communities were not the same as in the (semi)pristine phase. This is concerning as different species can deliver different ecosystem services, and therefore their inability to return to a particular site can prevent the reinstatement of specific services.

Niamh Eastwood, lead author and PhD student at the University of Birmingham said: "The biodiversity loss caused by this pollution and the warming water temperature is potentially irreversible. The species found in the lake 100 years ago that have been lost will not all be able to return. It is not possible to restore the lake to its original pristine state, even though the lake is recovering. This research shows that if we fail to protect biodiversity, much of it could be lost forever."

Dr Jiarui Zhou, co-lead author and Assistant Professor in Environmental Bioinformatics at the University of Birmingham, said: "Learning from the past, our holistic models can help us to predict the likely loss of biodiversity under a 'business as usual' and other pollution scenarios. We have demonstrated the value of AI-based approaches for understanding historic drivers of biodiversity loss. As new data becomes available, more sophisticated AI models can be used to further improve our predictions of the causes of biodiversity loss."

Next the researchers are expanding their initial study on a single lake to lakes in England and Wales. This new study will help them understand how replicable the patters they observed are and, therefore, how they can generalise their findings on pollution and climate change on lake biodiversity.

Carbon-capture tree plantations threaten tropical biodiversity for little gain, ecologists say

The increasingly urgent climate crisis has led to a boom in commercial tree plantations in an attempt to offset excess carbon emissions. However, authors of a peer-reviewed opinion paper publishing October 3 in the journal Trends in Ecology and Evolution argue that these carbon-offset plantations might come with costs for biodiversity and other ecosystem functions. Instead, the authors say we should prioritize conserving and restoring intact ecosystems.

"Despite the broad range of ecosystem functions and services provided by tropical ecosystems, society has reduced value of these ecosystems to just one metric -- carbon," write the authors, led by Jesús Aguirre-Gutiérrez of the Environmental Change Institute at the University of Oxford. "Current and new policy should not promote ecosystem degradation via tree plantations with a narrow view on carbon capture."

Tropical ecosystems, which include forests, grasslands, and savannahs, are attractive sites for tree plantations because their climate and physical features promote rapid tree growth (and rapid tree growth means rapid carbon capture). Although some tree plantations involve reforestation of degraded land, in many cases they involve afforestation -- planting forests in undegraded and previously unforested regions such as grasslands.

It's often assumed that tree planting for carbon capture also benefits biodiversity and enhances socioeconomic benefits, but the authors argue that this is usually not the case. Tropical ecosystems are highly biodiverse, and they provide multiple ecosystem services, such as maintaining water quality, soil health, and pollination. In comparison, carbon-capture plantations are usually monocultures and are dominated globally by just five tree species -- teak, mahogany, cedar, silk oak, and black wattle -- that are grown for timber, pulp, or agroforestry.

Although these plantations might be economically valuable, they usually support a lower level of biodiversity. For example, in the Brazilian Cerrado savannah, a 40% increase in woody cover reduced the diversity of plants and ants by approximately 30%. These plantations can also directly degrade ecosystems by reducing stream flow, depleting groundwater, and acidifying soils.

The authors argue that even ambitious commitments to carbon-capture plantations will be limited in their ability to capture carbon. "The current trend of carbon-focused tree planting is taking us along the path of large-scale biotic and functional homogenization for little carbon gain," the authors write. "An area equivalent to the total summed area of USA, UK, China, and Russia would have to be forested to sequester one year of emissions."

And tropical grasslands and savannahs are already carbon sinks. When intact, tropical grasslands and savannahs store large quantities of carbon below ground. In contrast to carbon-capture tree plantations, which predominantly store carbon above ground, these below-ground carbon sinks -- which would be lost if afforested -- are less susceptible to disturbances such as drought and fire.

The authors say that there are considerable financial incentives for private companies to offset their carbon emissions by investing in carbon capture and that the boom in carbon-capture plantations is being driven by money, not ecology. Compared to parameters such as biodiversity and ecosystem services, carbon is easy to measure and monetize. But overemphasizing the benefits of tree planting for carbon capture "can disincentive the protection of intact ecosystems and can lead to negative trade-offs between carbon, biodiversity, and ecosystem function," the authors write.

Instead of focusing on commercial tree planting, the authors say we should prioritize conserving intact ecosystems. "An overarching view on maintaining original ecosystem functioning and maximizing as many ecosystem services as possible should be prioritized above the ongoing economic focus on carbon capture projects," they write. 

New pipeline makes valuable organic acid from plants -- saving money and emissions

 In a breakthrough for environmentally friendly chemical production, researchers at the Center for Advanced Bioenergy and Bioproducts Innovation (CABBI) have developed an economical way to make succinic acid, an important industrial chemical, from sugarcane.

The team of University of Illinois and Princeton University researchers created a cost-effective, end-to-end pipeline for this valuable organic acid by engineering a tough, acid-tolerant yeast as the fermenting agent, avoiding costly steps in downstream processing. Succinic acid is a widely used additive for food and beverages and has diverse applications in agricultural and pharmaceutical products.

This same pipeline can be used to produce other industrially important organic acids targeted by CABBI in its work to develop sustainable biofuels and biochemicals from crops, said co-author Huimin Zhao, CABBI's Conversion Theme Leader and Professor of Chemical and Biomolecular Engineering (ChBE) at Illinois. To reduce reliance on fossil fuels, Conversion researchers are deploying microbes to convert plant biomass into chemicals used in everyday products as an alternative to conventional petroleum-based production.

"This will serve as a blueprint for all the other metabolic engineering products in CABBI," said Zhao, one of several CABBI principal investigators on the project. Other PIs included Vijay Singh, CABBI's Deputy Director for Science & Technology, Distinguished and Founder Professor of Agricultural and Biological Engineering (ABE), and Executive Director of the Integrated Bioprocessing Research Laboratory (IBRL) at Illinois; Jeremy Guest, Associate Professor of Civil & Environmental Engineering (CEE) at Illinois and part of CABBI's Sustainability Theme; and Conversion Deputy Theme Leader Joshua Rabinowitz, Professor of Chemistry and the Lewis-Sigler Institute for Integrative Genomics at Princeton.

The study, published in Nature Communications, is led by CABBI -- a U.S. Department of Energy Bioenergy Research Center -- and funded by BioMADE, a Manufacturing Innovation Institute with more than 230 member organizations around the country, including companies, universities, and nonprofit organizations. BioMADE was catalyzed by the U.S. Department of Defense and works to secure America's future through bioindustrial manufacturing innovation, education, and collaboration.

The work builds on years of research on succinic acid production by Zhao and his colleagues using Issatchenkia orientalis, an unconventional yeast ideal for making organic acids.

I. orientalis has the unique ability to thrive in low-pH, or acidic, conditions. Most organisms require a neutral pH environment to survive, including Saccharomyces cerevisiae, a more conventional yeast, or Escherichia coli bacteria. Both have been used by companies and labs to produce succinic acid but proved to be too costly, so efforts to scale up production have failed, Zhao said.

Those microorganisms require the addition of a base to neutralize the toxic acidic conditions so they can continue making succinic acid. But that generates side products, such as gypsum or calcium sulfate, which have to be separated out at the end of the pipeline to purify the product, driving up downstream processing costs.

"One of the bottlenecks in the production of organic acids is the separation cost," Zhao said. "We have to add a lot of base to keep the pH near neutral, between 6 to 7."

With I. orientalis, however, "the organism lives happily at a pH of 3 to 4," so the additives are not required, Zhao said. "In the end, that significantly reduces costs."

The CABBI researchers also did extensive metabolic engineering to rewire I. orientalis to produce robust levels of succinic acid -- higher than either S. cerevisiae or E. coli, he said. Using metabolic flux analysis from Rabinowitz's lab, they identified the steps in the yeast's metabolism that limited the production of succinic acid. One key roadblock: Native I. orientalis can't utilize the sucrose from sugarcane. So an enzyme was added that could break down sucrose from the sugarcane juice into glucose and fructose to make succinic acid. Other genes were introduced to overproduce succinic acid.

Working with Singh's group at IBRL, the team then scaled up succinic acid production using industrially relevant equipment to conduct an end-to-end integration of the process. The pilot-scale work showed the new strains could produce up to 110 g/L of succinic acid and, after batch fermentation and downstream processing, an overall yield of 64% -- impressive results having commercial significance, Singh said.

The combination of higher production levels through genetic engineering and lower costs from the elimination of downstream separation makes the process "very attractive," Zhao said. "That's why the pipeline is so economical, at least at this pilot scale."

The final step was working with Guest to simulate a full end-to-end, low-pH succinic acid production pipeline, using the open-source software platform BioSTEAM developed by his group. The techno-economic analysis (TEA) and life cycle assessment showed the process was financially viable and could reduce greenhouse gas emissions by 34% to 90% relative to fossil fuel-based production processes

"These advancements in metabolic engineering could have large-scale benefits, simultaneously driving down costs and environmental impacts in support of a circular bioeconomy," Guest said.

The process emits less carbon dioxide (CO2) than conventional petroleum-based chemical processing. Plants like sugarcane also soak up carbon, and CO2 can be used as a substrate for the process, further reducing its carbon footprint.

"It's definitely more environmentally friendly. That's the premise for all the research in CABBI: using renewable resources to make chemicals and fuels," Zhao said.

Researchers plan further scale-up studies soon to support commercialization of the succinic acid production process.

The work will also be a template for production of other CABBI products using I. orientalis, including 3-hydroxypropionic acid (3-HP). The market for 3-HP, used in components of disposable diapers and sealants, exceeds $1 billion, and research to date shows huge promise, Zhao said.

"We expect I. orientalis can serve as a general industrial platform for the production of a wide variety of organic acids," said Vinh Tran, primary author on the paper and a Ph.D. student in ChBE.

The project involved several lab groups and contributions from all three themes of CABBI's research -- using sugarcane juice from the Feedstock Production research team, metabolic research and bioprocessing facilities from the Conversion team, and economic and environmental analysis from the Sustainability team.

Co-authors included CABBI researchers Sarang Bhagwat of CEE and Yihui Shen of the Department of Chemistry at Princeton; Somesh Mishra of ABE; Saman Shafaei, Shih-I Tan, Zia Fatma, and Benjamin Crosly of ChBE; and Jayne Allen of CEE.

Pheromones influence death feigning behavior in beetles

 Predation is a driving force in the evolution of anti-predator strategies, and death feigning, characterized by immobility in response to threats, is a common defensive mechanism across various animal species. While this behavior can enhance an individual's survival prospects by reducing a predator's interest, it also carries costs, such as limited opportunities for feeding and reproduction. Recently, researchers from Okayama University, Japan, investigated how pheromones, important chemical signals that affect foraging and reproduction, might influence death-feigning behavior in the red flour beetle, Tribolium castaneum.

"Male beetles release an aggregation pheromone called 4,8-dimethyldecanal (DMD), which attracts both males and females, aiding in successful foraging and mating. However, it remained unclear whether this pheromone could affect the duration of death feigning in these beetles," says Professor Takahisa Miyatake from the Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, Japan, who led the study. Prof. Miyatake collaborated with colleagues Motoya Ishikawa and Kentarou Matsumura from the same department on this study. Their findings were published on 13 September 2023 in the Journal of Ethnology.

The team used a population of T. castaneum that had undergone artificial selection for death-feigning duration for more than 40 generations. The study encompassed two distinct experimental schedules. In the first, beetles were initially exposed to the pheromone, following which their death-feigning duration was measured. In the second schedule, beetles were first evaluated for their death-feigning duration without the presence of the pheromone, and subsequently, the duration was measured with the pheromone introduced. In both scenarios, the researchers meticulously compared the death-feigning durations between the treatments.

The team found that T. castaneum beetles exposed to the DMD pheromone exhibited significantly shorter durations of death feigning compared to their counterparts that were not exposed to the pheromone. This discovery suggests that the mere presence of the aggregation pheromone played a pivotal role in shaping the behavior of these beetles, causing them to curtail their protracted death feigning.

Interestingly, while previous research has primarily focused on the triggers for initiating death feigning, little has been known so far about what cues awaken individuals from this state. The study suggests that aggregation pheromones, like DMD, may serve as one of these awakening factors. This adaptive response allows individuals to save precious time and increase their chances of survival when predators lose interest.

Furthermore, the study brough to light the potential sex-related differences in death-feigning behavior. Previous studies had already indicated that both male and female adult red flour beetles exhibit a strong attraction to DMD, with males even intensifying DMD release upon sensing it. Remarkably, during this investigation, researchers noted that males tended to have a longer duration of death feigning when compared to females. This observation raises intriguing questions about how the sexes allocate their time and energy, particularly in the context of dispersal and reproductive activities.

"Our study suggests that T. castaneum possesses the capacity to adapt its death-feigning duration when it detects the presence of an aggregation pheromone. This represents a remarkable example of behavioral plasticity in response to external chemical cues, as shown by previous studies. This may offer valuable insights into the intricate world of animal instincts, potentially paving the way for further exploration in the future," concludes Prof. Miyatake.

Red flour beetles are known pests. They commonly forage on food products such as flour, grains, cereal, and stored goods. Therefore, studying how they respond to pheromones such as DMD could have enormous agricultural significance.

How new plant cell walls change their mechanical properties after cell division

 Scientists reveal new plant cell walls can have significantly different mechanical properties compared to surrounding parental cell walls, enabling cells to change their local shape and influence the growth of plant organs.

This is the first time that scientists have related mechanics to cell wall "age" and was only made possible through a new method that follows the same cells over time and through successive rounds of division.

The Cambridge researchers were able to see new walls forming and then measure their mechanical properties. This pioneering work showed that new cell walls in some plants are 1.5 times stiffer than the surrounding parental cell walls -- an unexpected and surprising finding.

The size and shape of plant organs like leaves and flowers is the result of complex interactions between genetics, signalling, mechanical feedback, and environmental cues. While we have made a lot of progress in understanding these processes, it is not always easy to connect what happens at the cellular scale with what happens at the organ scale.

Research undertaken on two distantly related plant species at the Sainsbury Laboratory Cambridge University (SLCU) provides new evidence suggesting local level cell division has an active role to play in controlling organ size. The interdisciplinary project was a collaboration between three SLCU research teams (Robinson Group, Schornack Group and Jönsson Group) and the SLCU Microscopy Facilities Team, bringing together expertise in experimental biomechanics, genetics, imaging and computational modelling.

Combining advanced live microscopy imaging of individual cells, advanced material characterisation methods, and mathematical modelling, Sarah Robinson's research group has revealed the process of cell division locally alters the mechanical properties of the growing tissue, which potentially impacts on the final shape and size of the plant organ. The findings were published in Proceedings of the National Academy of Sciences (PNAS) this week (6 October 2023).

Compared to animal cells, plant cells are enclosed by a rigid box -- the cell wall. Cell division involves the addition of new cell walls, which alter the mechanical stress in the cell, its geometry and the mechanical properties of the surrounding tissue.

Scientists have been able to probe the mechanical properties of individual cell walls in the outer cell layer of a plant organ, but they did not know how old each wall is and could only guess if it had just divided. First author of the paper, former researcher in the Robinson Group and now a research fellow at Politecnico di Milano, Alessandra Bonfanti followed cells over time and could see new walls forming and therefore was able to relate mechanics to cell wall "age."

Dr Bonfanti developed a protocol that combines time-course imaging with atomic force microscopy measurements (AFM) to systematically map the age, growth and mechanical properties (stiffness) of individual cells walls and to follow the same cell walls through successive rounds of division.

"We have known for some time that the cell wall is a highly dynamic material. New material is added during cell division, while cell wall mechanical properties are modulated during growth to allow walls to undergo significant changes in shape and size without breakage," Dr Bonfanti said. "Yet, how the mechanical properties of new cell walls transiently change in space and time was still unknown until we developed a new protocol that allowed us to measure the mechanical properties of cell walls over time."

"We used this protocol to address how the stiffness of newly formed cell walls varies at 24-hours and 48-hours up until its mature stage, and how this affects local cell shapes," Dr Bonfanti said. "To do so we made use of two systems: gemmae of the liverwort Marchantia polymorpha, and the early-stage first true leaf of Arabidopsis thaliana."

The cells in the young tissues of the two plant species studied initially have a similar square-shaped geometry, which made them good models to compare.

"We first characterised the growth and cell division pattern in M. polymorpha gemmae, which was still unclear in the literature," said Dr Bonfanti. "Then, with the optomechanical measurements, using time course imaging combined with AFM measurements, we demonstrated that cell division in M. polymorpha gemmae results in the generation of a temporary stiffer and slower growing new wall. In contrast, this transient phenomenon is absent in A. thaliana leaves."

In fact, the new cell walls in M. polymorpha became 1.5 times stiffer than the parental cell walls.

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"We have shown that there are significant differences in the stiffness of new cells walls compared to parental walls and that these differences contribute to the cell's geometry and growth," Group Leader Dr Robinson said. "This suggests cell division and its varying mechanical properties alters the rate of tissue expansion and could impact final organ size."

Dr Robinson explained the significance of the discovery: "We already knew that cell walls loosen and become softer when cells are growing as the walls must stretch so the cells can expand as they grow. But we didn't know what would happen when a cell divides and what properties the resulting new cell wall would have. Would they be the same or different to the walls in the surrounding tissue and how this would this impact cell growth?

"The fact that the new cell walls are much stiffer results in organ growth being restricted as it impedes the growth and influences the shape of component cells.

"The M. polymorpha cells also change their geometry and develop a 120° junction angle quicker to form cell geometries closer to hexagonal shapes, which are thought to be the most efficient shapes in terms of forming a material to cover an area. The computational modelling done in this project by Euan Smithers and Ross Carter provided evidence that the presence of a stiff new wall accelerates the formation of these 120° angles."

"It is important to know that the new cell wall can be different to the parental wall and this gives us new questions to explore -- is that always the case, in what conditions, and why is this the case?"

Caribbean parrots thought to be endemic are actually relicts of millennial-scale extinction

 In a new study published in PNAS, researchers have extracted the first ancient DNA from Caribbean parrots, which they compared with genetic sequences from modern birds. Working with fossils and archaeological specimens, they showed that two species thought to be endemic to particular islands were once more widespread and diverse. The results help explain how parrots rapidly became the world's most endangered group of birds, with 28% of all species considered to be threatened. This is especially true for parrots that inhabit islands.

On his first voyage to the Caribbean in 1492, Christopher Columbus noted that flocks of parrots were so abundant they "obscured the sun." Today, more than half of parrot species in the Caribbean have gone extinct, from large particolored macaws to a parrotlet the size of a sparrow.

Biologists attempting to conserve the remaining parrot species are stymied by how little is known of their former distributions. This is due, primarily, to their complicated history with humans.

"People have always been obsessed with parrots," said lead author Jessica Oswald, a senior biologist with the U.S. Fish and Wildlife Service Forensics Lab. "Indigenous peoples have moved parrots across continents and between islands for thousands of years. Later, European colonists continued that practice, and we're still moving them around today."

Centuries of exchange and trade have made it difficult to know how parrots wound up where they are now. Half of the 24 parrot species that currently live in the Caribbean were introduced from other areas, and it's unclear whether native parrots evolved on the islands they inhabit or were similarly transported there.

Fortunately, their popularity with humans means parrots are occasionally found in archaeological sites as well. Their bones have been recovered from refuse piles -- called middens -- alongside shells, fish bones and other scraps from previous meals.

"There are records of parrots being kept in homes, where they were valued for their feathers and, in some cases, potentially as a source of food," said senior author Michelle LeFebvre, curator of South Florida archaeology and ethnography at the Florida Museum of Natural History.

Parrots also have an uncharacteristically good fossil record in the Caribbean, compared with other tropical regions. However, specimens are rarely found intact. More often, their bones are broken or isolated, and it's not always possible to determine which species they belonged to.

DNA can provide unequivocal answers where physical comparisons fall short, and co-author David Steadman was eager to see if they could extract any residual genetic material preserved in bone tissue. Oswald -- who worked as a graduate student and postdoctoral associate at the Florida Museum -- had recently completed a proof of concept, in which she successfully sequenced the first DNA from an extinct Caribbean bird that had been preserved in a blue hole for 2,500 years. Using the same methods, she later discovered that an extinct flightless bird from the Caribbean was most closely related to similarly bygone, ground-dwelling birds from Africa and New Zealand.

"For me, the single most satisfying thing about this project is we can use fossils in ways that weren't even imaginable when they came out of the ground," said Steadman, a retired curator of ornithology at the Florida Museum.

The authors pieced together the long history of parrots in the genus Amazona, focusing on two species -- the Cuban (A. leucocephala) and Hispaniolan (A. ventralis) parrots -- for which they could obtain ancient DNA samples.

Of the two, Cuban parrots are currently the most widespread, with isolated populations in Cuba and on a few islands in the Bahamas and Turks and Caicos. They're one of the only native parrots in the region not in imminent danger of extinction.

The Hispaniolan parrot has had a harder time adapting to human-wrought changes. It's listed as vulnerable to extinction on the International Union for Conservation of Nature's Red List and is entirely endemic to its eponymous island.

Most of the fragmentary fossils collected outside of Hispaniola and Puerto Rico were consequently identified as belonging to the more common Cuban parrots. But when the DNA results came back, they told a different story. The fossils from the Bahamian paleontological sites were actually from Hispaniolan parrots, indicating that this species formerly had a range that extended up through the Bahamas before human arrival to the islands.

Similarly, the results indicate that Cuban parrots once inhabited the largest island in the Turks and Caicos, from which they are now absent.

"One of the striking things about this study is the discovery of what could be considered dark extinctions," LeFebvre said. "We're learning about diversity we didn't even know existed until we took a closer look at museum specimens."

Bones from archaeological sites in the Turks and Caicos and from Montserrat -- an island far to the south in the Lesser Antilles -- were also determined to be from Hispaniolan parrots. These had likely been transported there by humans, and the species is no longer present on the islands.

According to Oswald, knowing where species once thrived -- both naturally by their own devices and artificially with the aid of humans -- is the first step to conserving what's left of their diversity.

"We have to think about what we consider to be natural," she said. "People have been altering the natural world for thousands of years, and species that we think are endemic to certain areas might be the product of recent range loss due to humans. It takes paleontologists, archaeologists, evolutionary biologists and museum scientists all working together to really understand the long-term role of humans on diversity change."

The authors published their study in the journal PNAS. Brian Smith of the American Museum of Natural History, Julie Allen of Virginia Tech and Robert Guralnick of the Florida Museum of Natural History are also co-authors on the study.

Theories about the natural world may need to change to reflect human impact

 New research, reported in Nature Ecology & Evolution, (25 September 2023) has for the first time validated at scale, one of the theories that has underpinned ecology for over half a century. In doing so, the findings raise further questions about whether models should be revised to capture human impacts on natural systems.

Scientists working in the 50's and 60's developed theories to predict the ecological distribution of species. These theories could be applied across a broad range of environments and variables such as food supply or temperature and when tested on a small scale they were found to be accurate. Amongst the earliest examples of these theories is the coral reef zonation theory which explains how different types of fish or corals for example are found on coral reefs at different depths.

Modern computing capabilities have now made it possible to test these theories at a larger scale, to see whether they 'hold water'.

To validate the depth zonation model on coral reefs, scientists at Bangor University and the US Government National Oceanic and Atmospheric Administration (NOAA), led by Dr Laura Richardson, of Bangor University, collected data from 5525 surveys at 35 Pacific Ocean islands. Their work has revealed that the model is correct and can predict the distribution of different fish species according to depth, but only on uninhabited islands where there is no and has never been any local human interference.

At islands and reefs with human habitation the pattern was not as marked or predictable.

The findings therefore suggest that our old 'models' of the natural world may no longer be valid in the face of mounting local human impacts.

As lead author, Dr Laura Richardson of Bangor University's School of Ocean Sciences, suggests, "Science is cumulative, building on past work. Now that we have greater computing capabilities, we should be testing these widely accepted but spatially under-validated theories at scale. Moreover the intervening years have seen human impacts on the environment increase to such an extent that these models may no longer predict the ecological distribution patterns we see today.

"This leads to more questions, both about the usefulness of models which represented a world less impacted by human activity, and about how to quantify or model our impact on the natural environment."

"The results show that now is the time to consider whether and how to include human impacts into our understanding of the natural world today."

Scientists reveal what fuels wildfires in Sierra Nevada Mountains

 Wildfires in California, exacerbated by human-driven climate change, are getting more severe. To better manage them, there's a growing need to know exactly what fuels the blazes after they ignite. In a study published in Environmental Research Letters, Earth system scientists at the University of California, Irvine report that one of the chief fuels of wildfires in California's Sierra Nevada mountains is the decades-old remains of large trees.

"Our findings support the idea that large-diameter fuel build-up is a strong contributor to fire severity," said Audrey Odwuor, a Ph.D. candidate in the UCI Department of Earth System Science and the lead author of the new study.

Researchers have known for decades that an increasing number of trees and an increasing abundance of dead plant matter on forest floors are the things making California wildfires more severe -- but until now it was unclear what kinds of plant debris contribute most to a fire.

To tackle the question, Odwuor and two of the study's co-authors -- James Randerson, professor of Earth system science at UCI, and Alondra Moreno from the California Air Resources Board -- drove a mobile lab owned and operated by the lab of study co-author and UCI alumna Francesca Hopkins at UC Riverside, to the southern Sierra Nevada mountains during 2021's KNP Complex Fire.

The KNP Complex Fire burned almost 90,000 acres in California's Sequoia and Kings Canyon National Parks. In the fire's smoke, the team took samples of particulate matter-laden air and analyzed the samples for their radiocarbon content at UCI's W.M. Keck Accelerator Mass Spectrometer facility with co-author and UCI Earth system science professor Claudia Czimczik.

Different fuel types, explained Czimczik, have different radiocarbon signatures, such that when they analyzed the smoke they discovered radiocarbon values associated with large fuel sources like fallen tree logs.

"What we did was pretty distinctive, as we were able to identify fuel sources by measuring the wildfire smoke," said Czimczik. "Our approach provides what we think of as an integrated picture of the fire because we're sampling smoke produced over the course of the fire that has been transported downwind."

The team also saw elevated levels of particulate matter that is 2.5 microns in diameter or less, which includes particles that, if inhaled, are small enough to absorb into the bloodstream.

The preponderance of large-diameter fuels is new in western forests. "We're really in a situation that's a consequence of both management strategies and climate warming since European-American settlement began in California," Odwuor said. "These fuels are building up on the forest floor over periods of decades, which is not typically how these forests were maintained."

It's information that, according to Odwuor, could help California better manage its wildfires.

"The knowledge that large-diameter fuels drive fires and fire emissions -- at least in the KNP Complex Fire -- can be useful for knowing which fuels to target with fuel treatments and what might end up in the smoke from both wildfires and prescribed fire," said Odwuor. "The idea is that because we can't control the climate, we can only do our best to manage the fuels, which will theoretically have an impact on fire severity and the composition of the smoke."

But the solution isn't as straightforward as removing trees from forest floors, because, among other things, they provide habitat for wildlife. That, and "once you get them out, where do you send them? There are only so many mills in California that can handle all the wood," Odwuor said.

Where the new knowledge could be helpful is with prescribed burns, wherein teams burn tracks of forest in a planned fashion with the aim of reducing the amount of fuel available for future wildfires.

"We're hoping to build some urgency for these management strategies," said Odwuor.

By air, rain and land: How microbes return after a wildfire

 The disruption brought by wildfires reaches everything that lives in or near a burning field or forest -- including microbes. A better understanding of how microbial communities change and grow after a fire could help researchers predict how bacteria and fungi will respond to major environmental changes.

A study published this week in mSystems suggests that dispersal -- through air or rain, for example -- plays a major role in microbial succession after a destructive fire. Researchers at the University of California, Irvine, spent a year tracking how bacterial and fungal communities returned to the leaf litter in a burned field. They found that the emerging microbial communities in the soil surface changed with the seasons and the reappearance of plants, and that the assembly of those communities was largely driven by dispersal.

The risk and extent of big, ecological disturbances like wildfires have been increasing in the last few decades.

"We know with climate change and human activity we're disturbing our ecosystems more and more," said Kristin Barbour, lead author on the new study and a Ph.D. student at the University of California, Irvine. "Microbes, especially those in the surface soil, perform a number of really key ecosystem processes, like carbon and nitrogen cycling." Bacteria and fungi, she said, break down the dead and decaying plant matter on the floor of a field or forest.

Barbour originally set out to study microbial dispersal in the context of droughts, but her plans changed after an unplanned wildfire burned a field site at Loma Ridge, near Irvine. What seemed like a setback became an opportunity. "We wanted to take advantage of this disturbance, especially since wildfire is becoming more frequent in many parts of the world," Barbour said.

The intense heat produced during a wildfire alters the chemical composition of the leaf litter, where microbes reside, and can shift the microbial communities in an ecosystem.

The researchers looked at 2 ecosystems that had been affected by the fire: a semi-arid grassland and a coastal sage scrub. To study the movement of microbes, they used 4 configurations of dispersal bags. For the first, they used burned leaf litter to fill small porous pouches that allowed microbes to pass in and out. For the second, a control group, they sealed leaf litter in bags that did not allow movement in or out. The third configuration was a porous bag filled with glass slides, to collect microbes as they moved through, and the fourth, another control group, included closed bags with glass slides.

At 5 times during the year after the fire, Barbour and her colleagues collected dispersal bags from both sites and identified bacteria and fungi on the leaf litter. They found that the effect of dispersal differed in the two environments, suggesting that microbial responses are dependent on their environment. "Which hurts our ability to make generalized statements," Barbour said.

They did see some recurring patterns. Overall, dispersal from the air contributed most significantly to the microbes entering the soil surface -- 34% of the bacteria and 42% of the fungi. They also found that in the first few months after the fire, before plants had re-emerged, bulk soil (the soil beneath the leaf litter) explained the largest share of immigrating bacteria.

The study of how microbes move through the environment is an emerging area of research, Barbour said, but one that's intimately connected to larger issues of how big disturbances change the environment.

"There's a lot of exciting work being done right now, looking at dispersal and at microbial communities out in the environment," she said.

Ag tech can cut billions of tons of greenhouse gas emissions

 As the Earth's human population grows, greenhouse gas emissions from the world's food system are on track to expand. A new study demonstrates that state-of-the-art agricultural technology and management can not only reduce that growth, but eliminate it altogether by generating net negative emissions -- reducing more greenhouse gas than food systems add.

In fact, employing additional agricultural technology could result in more than 13 billion tons of net negative greenhouse gas emissions each year, as the world seeks to avoid dangerous climate extremes, according to research published Sept. 6 in PLOS Climate.

The work was led by Benjamin Z. Houlton, the Ronald P. Lynch Dean of the College of Agriculture and Life Sciences at Cornell University, and Maya Almaraz, associate research scholar at Princeton University.

"Our study recognizes the food system as one of the most powerful weapons in the battle against global climate change," said Houlton. "We need to move beyond silver-bullet thinking and rapidly test, verify and scale local solutions by leveraging market-based incentives."

The world's food system network generates between 21% and 37% of the planet's greenhouse gas emissions each year. With the global population approaching 10 billion by mid-century, greenhouse gas emissions of the global food system -- if left unchecked -- could grow to 50% and 80% by 2050, according to the paper.

Previous research has indicated that changing diets around the world is a key to reducing greenhouse gas in the food-system sector. But Houlton and Almaraz believe the emission reduction could be much greater.

If the entire human population adopted a so-called "flexitarian" diet by 2050 -- which is promoted by the EAT-Lancet Commission (a group of world experts who established a nutritious, healthy and sustainable diet) -- the scientists estimated a gross reduction of 8.2 billion metric tons of greenhouse gas emissions, which falls far short of the net negative emissions goal.

"Our study examines both dietary change and agricultural technologies, as various options for slashing emissions," Almaraz said. "This included an analysis of carbon sequestration."

In contrast to the marked benefit of agricultural technology in realizing massive sector-wide negative emissions, dietary changes had little effect on carbon sequestration, according to the study. "We only looked at about a dozen technologies," Almaraz said. "But there are even more under development, which hold a lot of promise for the food system."

The new model showed that the most effective way to reduce emissions is to boost soil modifications for crops (biochar, compost and rock amendments), develop agroforestry, advance sustainable seafood harvesting practices and promote hydrogen-powered fertilizer production.

In a process called "enhanced weathering," for example, silicate rock dust can be added to crop soils every five years to accelerate the formation of carbonates. This process devours carbon dioxide, which can sequester several billion metric tons of carbon per year, according to the paper.

Through agroforestry, planting trees on unused farmland can impound up to 10.3 billion metric tons of carbon annually, while seaweed can be farmed at the ocean surface and then buried in the deep sea, removing up to 10.7 billion metric tons of carbon dioxide.

Supplementing livestock feed with additives could reduce methane emissions by 1.7 billion metric tons and applying biochar to croplands may reduce nitrous oxide emissions by 2.3 billion metric tons.

Food-system environmental action needs to start regionally. Houlton said that anaerobic digesters have been converting manure from New York's dairy farms into electricity since the mid-1970s, reducing emissions, supporting energy self-sufficiency, and assisting in water quality improvements. The biogas resulting from the waste becomes energy that local electric companies can easily use, but this approach must avoid gas leaks and financial incentives are still necessary. "We need a portfolio of solutions that are effective locally but have global impact," he said.

"If people choose to switch to healthier diets, as suggested by EAT-Lancet -- and if they can afford it -- great," Houlton said. "But to get the world to net negative greenhouse gas emission -- a global imperative to avoid the most dangerous climate impacts -- we need to rely heavily on agricultural technology and management techniques."

Early work on this research was conducted by Houlton when he was the director of the University of California, Davis Institute of the Environment while Almaraz was a postdoctoral researcher at the World Wildlife Fund/ National Center for Ecological Analysis and Synthesis at University of California, Santa Barbara.

In addition to Houlton and Almaraz, co-authors on the research, "Model-Based Scenarios For Achieving Net Negative Emissions in the Food System," are Xingen Lei, professor of animal science and associate dean of research and innovation (CALS); doctoral student Yanqiu Zhou; Michael Clark, University of Oxford; Iris Holzer, Erin Manaigo, Benjamin S. Halpern, Courtney Scarborough all from the University of California, Davis; Laura Rasmussen, University of Copenhagen,; Emily Moberg and Melissa Ho, World Wildlife Fund; Edward Allison, WorldFish, Penang, Malayasia; Lindiwe Sibanda, Alliance for a Green Revolution in Africa, Nairobi; and Andrew Salter, University of Nottingham.

Invasive spotted lanternfly may not damage hardwood trees as previously thought

 In 2012, when the spotted lanternfly (Lycorma delicatula) arrived in the U.S. from its home in China, scientists, land managers, and growers were understandably concerned that the sap-feeding insect would damage native and commercial trees. New long-term research led by Penn State has discovered that hardwood trees, such as maple, willow and birch, may be less vulnerable than initially thought.

"Since the lanternfly was first introduced to the northeastern U.S., the question has been, 'How at-risk are our forests?' said Kelli Hoover, professor of entomology at Penn State. "So far, we haven't had a good answer. Our study is the first to look at the long-term impacts of feeding pressure on northeastern hardwoods, and our results suggest that we are unlikely to see big impacts on the growth of trees."

The findings published in the journal Environmental Entomology on August 29.

To determine the long-term effects of spotted lanternfly (SLF) feeding on hardwood trees, the team built large enclosures containing multiple species of tree, including the insect's favorite food, the non-native tree-of-heaven (Ailanthus altissima), as well as native trees, including silver maple (Acer saccharinum), weeping willow (Salix babylonica) and river birch (Betula nigra). The team included tree-of-heaven in half of the enclosures to determine whether its presence would influence the feeding pressure on the native hardwoods.

Within the enclosures, the researchers reared different densities of spotted lanternflies for all or most of their lifecycle, from eggs through adults, to see if the number of insects feeding on a tree would impact its growth and survival. After the first two years, they reduced the density of the insects to see if trees would recover. They monitored leaf gas exchange and concentrations of nutrients that are important for photosynthesis and growth for the first two years and tree diameter growth for the full four years.

The team found that increased feeding pressure by spotted lanternfly resulted in reductions in key nutrients, which in turn, markedly impacted tree diameter growth during the first two years when feeding pressure was the most intense. However, in year three when the feeding pressure was reduced, the native trees recovered while tree-of-heaven's growth remained flat. Leaf gas exchange did not differ significantly among the treatments.

"In the wild, we have seen that spotted lanternfly population numbers vary greatly from year to year on individual trees, and they move frequently among host trees," Hoover said. "Our study represents a worst-case scenario in which the spotted lanternfly fed on the same trees for four consecutive growing seasons. While we did see reduced growth after two years of intense feeding, the native trees recovered when feeding was less intense. Importantly, over the four years, none of the trees died. Therefore, in a natural setting where the insects are constantly on the move, we would not expect significant negative impacts on forest or ornamental trees."

Hoover noted that these findings may come as a relief to growers.

She said, "If I had an apple or peach orchard, I wouldn't even treat my trees with insecticides because we've learned that the insects are not going to stick around, and the cost of treating and the potential non-target impacts of the insecticides are just not worth it."

Other authors on the paper include Lidiia Lavorivska, postdoctoral fellow, Penn State; Emily Lavely, tree fruit educator, Michigan State University; Osariyekemwen Uyi, research scientist, University of Georgia; Brian Walsh, extension educator, Penn State; Emelie Swackhamer, extension educator, Penn State; Anne Johnson, graduate student in entomology, Penn State; and David Eissenstat, professor emeritus of wo

Farms that create habitat key to food security and biodiversity

 It seems intuitive that forests would provide better habitat for forest-dwelling wildlife than farms. Yet, in one of the longest-running studies of tropical wildlife populations in the world, Stanford researchers found that over 18 years, smaller farms with varying crop types -- interspersed with patches or ribbons of forest -- sustain many forest-dependent bird populations in Costa Rica, even as populations decline in forests.

In a paper published Sept. 4 in the Proceedings of the National Academy of Sciences, Nicholas Hendershot and colleagues compared trends in specific bird populations across three landscape types in Costa Rica: forests, diversified farms, and intensive agriculture. The steepest declines were found in forests, then in intensive agriculture (and the species succeeding in intensive agriculture were often invasive). But on diversified farms, a significant subset of bird species typically found in forests, including some of conservation concern, actually increased over time.

"Birds are kind of a proxy we use to track the health of ecosystems. And the birds we're seeing today aren't the same as we saw 18 to 20 years ago. This paper really documents this pattern," said Hendershot, a postdoctoral fellow at the time of this research in Stanford's Department of Biology in the School of Humanities and Sciences (H&S), the Stanford Center for Conservation Biology (CCB), and the Stanford-based Natural Capital Project (NatCap).

Food security at stake

While this research implies that diversified farming could be key for biodiversity, the relationship goes both ways: biodiversity is key for food security. In this case, that means having a variety of types of birds feeding on insects and helping to pollinate crops.

"Identity does seem to matter a lot for pest control and other ecosystem services birds provide. These species are not interchangeable," said Hendershot.

"We need a constant stream of pollinators servicing farms. About three-quarters of the world's crops require pollinators to some extent, and that 75% is our most nutritious food -- think of all the vitamins and minerals packed into fruits, nuts, and veggies," explained Gretchen Daily, faculty director of NatCap and CCB, Bing Professor of Environmental Science in H&S, and a senior author on the paper. "We need a constant stream of birds, bats, and other wildlife to help control pests: they suppress the vast majority naturally. And we need to start building flood protection, water purification, carbon storage, and many other vital benefits back into agricultural landscapes, way beyond what can be achieved in protected areas alone."

Daily also noted that, in terms of food production, diversified farms are not necessarily lower yielding than intensive agriculture. "This is a recent assumption that is being overturned," she said.

Evolving elegance: Scientists connect beauty and safeguarding in ammonoid shells

 With 350 million years of evolution culminating in almost two centuries of scientific discourse, a new hypothesis emerges from the B CUBE -- Center for Molecular Bioengineering at TU Dresden University of Technology. B CUBE researchers propose a new explanation for why ammonoids evolved a highly elaborate, fractal-like geometry within their shells. Their analysis shows that the increasing complexity of shell structures provided a distinct advantage by offering improved protection against predators. The findings are published in the journal Science Advances.

Ammonoids are a group of extinct marine mollusk animals that are now an iconic fossil group often collected by amateurs. Over 350 million years of evolution, ammonoids developed increasingly elaborate shells with fractal-like geometry. For nearly 200 years, scientists have debated the reason why these animals show a trend of increasing complexity in their shell structures. Dr. Robert Lemanis and Dr. Igor Zlotnikov from the B CUBE -- Center for Molecular Bioengineering at TU Dresden created mechanical simulations of theoretical and computed tomography-based models to unveil a potential explanation: the intricate architecture of these shells may have been nature's ingenious defense strategy against a wide array of predators.

"Over the course of 350 million years of evolution, ammonoids repeatedly evolved shells with increasingly complex inner walls. The persistence and repetitiveness of this trend imply some driving force; the question that has long remained unanswered is: what driving force? Opposition to water pressure, muscle attachments, respiration, Cartesian devils. All of these have been proposed as explanations for this trend but evidence for them is scarce. So we decided to explore a neglected idea," explains Dr. Robert Lemanis, researcher in Dr. Zlotnikov's group at the B CUBE.

The team's findings propose a fascinating correlation between the evolving complexity of the ammonoid shell and its resilience against external forces. As these ancient creatures roamed the oceans, their shells shielded them against predators and other environmental factors. The intricate inner structures provided crucial reinforcement, making it progressively harder for predators to crack them.

"Consider that the ammonoid shell was a relatively thin structure and once it was fractured, the animal could not repair it. A robust shell -- one that can resist the damage -- provided higher chances of survival," explains Dr. Lemanis.

In essence, the shell's evolution could be a story of survival against the odds. Through countless years of adaptation and innovation, these ancient creatures crafted their defenses with remarkable precision. This new insight from the B CUBE researchers offers us a glimpse into the distant past, where the beauty of nature intertwines with the relentless pressures of survival.

"Our work bridges biology and engineering, underscoring how animals harness the power of fractal morphology to design more robust biomaterials. It can provide inspiration for resilient structural designs," summarizes Dr. Zlotnikov, research group leader at the B CUBE.

Hidden moles in hidden holes

 Scientists have identified two types of mole which they believe have been living undiscovered in the mountains of eastern Turkey for as many as 3 million years.

The new moles -- named Talpa hakkariensis and Talpa davidiana tatvanensis -- belong to a familiar group of subterranean, invertebrate-eating mammals found across Europe and Western Asia.

While only one species, Talpa europaea, is found in Britain, further east there are a number of different moles, many of which have very small geographical ranges.

The researchers -- using cutting edge DNA technology -- have confirmed the new forms are biologically distinct from others in the group.

Both inhabit mountainous regions in eastern Turkey, and are able to survive in temperatures of up to 50°C in summer and being buried under two metres of snow in winter.

The study, published in the Zoological Journal of the Linnean Society, was conducted by researchers from Ondokuz May's University (Turkey), Indiana University (USA), and the University of Plymouth (UK).

Senior author David Bilton, Professor of Aquatic Biology at the University of Plymouth, has previously been responsible for identifying almost 80 new species of animals, particularly insects, and said the new discoveries were notable for a number of reasons.

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"It is very rare to find new species of mammals today," he said. "There are only around 6,500 mammal species that have been identified across the world and, by comparison, there are around 400,000 species of beetles known, with an estimated 1-2 million on Earth. Superficially, the new moles we have identified in this study appear similar to other species, since living underground imposes serious constraints on the evolution of body size and shape -- there are a limited number of options available for moles really. Our study highlights how, in such circumstances, we can under-estimate the true nature of biodiversity, even in groups like mammals, where most people would assume we know all the species with which we share the planet."

The discoveries mean that the number of known Eurasian moles has been raised from 16 to 18, and each have their own distinct genetic and physical characteristics.

To identify their latest finds, the researchers studied the size and shape of various bodily structures, using advanced mathematical analyses, which also allowed them to include specimens collected in the 19th century that are still available in museum collections.

A complementary analysis of the moles' DNA, and a detailed comparison with known species, then confirmed their distinctiveness.

As a result, Talpa hakkariensis -- found in the Hakkari region of southeastern Turkey -- was identified as a new species of mole, highly distinctive in terms of both its morphology and DNA.

Talpa davidiana tatvanensis -- found near Bitlis, also in southeastern Turkey -- was also identified as being morphologically distinct but has been classified as a subspecies of Talpa davidiana. First identified in 1884, T. davidiana it is listed as data deficient by the International Union for Conservation of Nature (IUCN).

Professor Bilton added: "We have no doubt that further investigations will reveal additional diversity, and that more new species of mole remain undiscovered in this and adjacent regions. Amid increasing calls to preserve global biodiversity, if we are looking to protect species we need to know they exist in the first place. Through this study, we have established something of a hidden pocket of biodiversity and know far more about the species that live within it than previously. That will be critical for conservation experts, and society as a whole, when considering how best to manage this part of the planet."