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  • These bats use their penis as an “arm” during sex but not for penetration

    These bats use their penis as an “arm” during sex but not for penetration

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    Newswise — Mammals usually mate via penetrative sex, but researchers report November 20 in the journal Current Biology that a species of bat, the serotine bat, (Eptesicus serotinus) mates without penetration. This is the first time non-penetrative sex has been documented in a mammal. The bats’ penises are around seven times longer than their partners’ vaginas and have a “heart-shaped” head that is seven times wider than the vaginal opening. Both the penises’ size and shape would make penetration post-erection impossible, and the researchers show that, rather than functioning as a penetrative organ, the bats use their oversized penises like an extra arm to push the female’s tail sheath out of the way so that they can engage in contact mating—a behavior that resembles “cloacal kissing” in birds.

    “By chance, we had observed that these bats have disproportionately long penises, and we were always wondering ‘how does that work?’,” says first author Nicolas Fasel of the University of Lausanne. “We thought maybe it’s like in the dog where the penis engorges after penetration so that they are locked together, or alternatively maybe they just couldn’t put it inside, but that type of copulation hasn’t been reported in mammals until now.”

    Very little is known about how bats have sex, and most previous observations of bats mating have only perceived the backs of mating pairs. In this study, the researchers were able to observe the bats’ genitalia during copulation by using footage from cameras that were placed behind a grid that the bats could climb on.

    Fasel collaborated with a bat rehabilitation center in Ukraine that opportunistically filmed mating pairs and with a bat enthusiast and citizen scientist, Jan Jeucken, who filmed hours of footage of serotine bat in a church attic in the Netherlands. Altogether, the team analyzed 97 mating events—93 from the Dutch church and 4 from the Ukrainian bat rehabilitation center.

    The video recordings revealed that the bats do not engage in penetrative sex. The researchers did not observe penetration at any point during the recorded mating events and noted that the erectile tissues of the penis were enlarged before they made contact with the vulva. During mating, the male bats grasped their partners by the nape and moved their pelvises (and fully erect penises) in a probing fashion until they made contact with the female’s vulva, at which point they remained still and held the females in a long embrace. On average, these interactions lasted less than 53 minutes, but the longest event extended to 12.7 hours. Following copulation, the researchers observed that the female bats’ abdomens appeared wet, suggesting the presence of semen, but further research is needed to confirm that sperm was transferred during these putative mating events.

    The researchers also characterized the morphology of serotine bat genitalia by measuring the erect penises of live bats that were captured as part of other research studies (serotine and other vesper bats are conveniently known to get erections under anesthesia) and by performing necropsies on bats that died at bat rehabilitation centers. Their measurements showed that, when erect, serotine bat penises are around seven times longer and seven times wider than serotine bat vaginas, and about a fifth as long as the bats’ head-body length. The bats also have unusually long cervixes, which could help female bats select and store sperm.

    The researchers speculate that the bats may have evolved their oversized penises in order to push aside the female bats’ tail membranes, which females may use to avoid sex. “Bats use their tail membranes for flying and to capture the insects, and female bats also use them to cover their lower parts and protect themselves from males,” says Fasel, “but the males can then use these big penises to overcome the tail membrane and reach the vulva.”

    Next, the researchers plan to study bat mating behavior in more natural contexts, and they are also investigating penis morphology and mating behavior in other bat species. “We are trying to develop a bat porn box, which will be like an aquarium with cameras everywhere,” says Fasel.

     

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    This research was supported by the National Science Centre of Poland, the Swiss National Science Foundation, and the Oleksandr Feldman Foundation.

    Current Biology, Fasel et al., “Mating without intromission in a bat, a novel copulatory pattern in mammals” https://cell.com/current-biology/fulltext/S0960-9822(23)01304-0

    Current Biology (@CurrentBiology), published by Cell Press, is a bimonthly journal that features papers across all areas of biology. Current Biology strives to foster communication across fields of biology, both by publishing important findings of general interest and through highly accessible front matter for non-specialists. Visit: http://www.cell.com/current-biology. To receive Cell Press media alerts, contact [email protected].

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  • Magnet manipulation guides muscle fiber alignment in tissue.

    Magnet manipulation guides muscle fiber alignment in tissue.

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    Newswise — Stimulating muscle fibers with magnets causes them to grow in the same direction, aligning muscle cells within tissue, Massachusetts Institute of Technology (MIT) and Boston University investigators report October 20 in the journal Device. The findings offer a simpler, less time-consuming way for medical researchers to program muscle cell alignment, which is strongly tied to healthy muscle function.

    “The ability to make aligned muscle in a lab setting means that we can develop model tissues for understanding muscle in healthy and diseased states and for developing and testing new therapies that combat muscle injury or disease,” says senior author Ritu Raman (@DrRituRaman), an MIT engineer. A better understanding of the rules that govern muscle growth could also have applications in robotics, she adds.

    In a previous investigation, Raman and colleagues found that “exercising” muscle fibers by making them contract in response to electrical stimulation for 30 minutes a day over the course of 10 days made the fibers stronger. This time, the researchers wanted to explore whether mechanically stimulating the muscle fibers over the same time frame (rather than letting them respond on their own) would have the same result. To investigate, they developed a method to mechanically stimulate muscle tissue that differs from typical lab techniques.

    “Generally, when people want to mechanically stimulate tissues in a lab environment, they grasp the tissue at both ends and move it back and forth, stretching and compressing the whole tissue,” said Raman. “But this doesn’t really mimic how cells talk to each other in our bodies. We wanted to spatially control the forces between cells within a tissue, matching native systems.”

    To stimulate the muscle cells in a more true-to-life way, Raman and her team grew cells in a Petri dish on a soft gel that contained magnetic particles. When they would move a magnet back and forth under the gel, the particles moved back and forth, too, which “flexed” the cells. The researchers could precisely control the way the gel moved, and, in turn, the magnitude and direction of the forces the cells within experienced, by changing the strength and orientation of the magnet. To measure the alignment of the muscle fibers within the tissues and whether they contracted in synchrony, the team’s collaborators at Boston University developed a custom software that automatically tracked videos of the muscle and generated graphs of its movement.

    “We were very surprised by the findings of our study,” said Raman. While mechanically stimulating the muscle fibers over the 10-day period did not seem to make them any stronger, it did cause them all to grow in the same direction.

    “Furthermore, we were excited to find that, when we triggered muscle contraction, aligned muscle was beating synchronously, whereas non-aligned muscle was not beating rhythmically,” said Raman. “This confirmed our understanding that the form and function of muscle are intrinsically connected, and that controlling form can help us control function.”

    Raman and colleagues plan to take the study further by investigating how different mechanical stimulation regimens impact both healthy and diseased muscle fibers. Additionally, they plan to study how mechanical stimulation affects other types of cells.

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  • The mechanism of tuberculosis infection via cord-like bacterial aggregates.

    The mechanism of tuberculosis infection via cord-like bacterial aggregates.

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    Newswise — The ability of Mycobacterium tuberculosis (MTB), a serious respiratory infection, to form snake-like cords was first noted nearly 80 years ago. In a study published October 20 in the journal Cell, investigators report the biophysical mechanisms by which these cords form and demonstrate how several generations of dividing bacteria hang together to create these structures that enable resistance to antibiotics.

    “Our work clearly showed that cord formation is important for infection and why this highly ordered architecture might be important for pathogenesis,” says senior author Vivek Thacker (@DrVivekThacker), who led the work at the Global Health Institute at École Polytechnique Fédérale de Lausannen (EPFL) in Switzerland and is now based at the Department of Infectious Diseases at Heidelberg University in Germany.

    The study used a unique combination of technologies to address the role of MTB cord formation. One was a lung-on-chip model, which allowed the researchers to get a direct look at “first contact” between MTB and host cells at the air-liquid interface in the lungs. This revealed that cord formation is prominent in early infection. The researchers also used a mouse model that develops pathologies mimicking human tuberculosis, allowing them to obtain tissue that could be studied using confocal imaging and confirming that cording also occurs early in infection in vivo.

    The work yielded several new findings about how these cords interact with and compress the cell nucleus, how this compression affects the immune system and connections between host cells and epithelial cells, and how cord formation affects the alveoli in the lungs. The study also revealed how these cords retain their structural integrity and how they increase tolerance to antibiotic therapy.

    “There is an increasing understanding that these mechanical forces influence cellular behavior and responses, but this aspect has been overlooked since traditional cell culture models do not recapitulate the mechanical environment of a tissue,” says Melanie Hannebelle (@MelanieHanneb), formerly at EPFL’s Global Health Institute and now at Stanford University. “Understanding how forces at the cellular and tissue level or crowding at the molecular level affects cell and tissue function is therefore important to develop a complete picture of how biosystems work.”

    “By thinking of MTB in infection as aggregates and not single bacteria, we can imagine new interactions with host proteins for known effectors of MTB pathogenesis and a new paradigm in pathogenesis where forces from bacterial architectures affect host function,” says Thacker.

    Future research will focus on understanding whether cord formation enables new functionality to known effectors of MTB pathogenesis, many of which are located on the MTB cell wall. In addition, it will look at the consequence of tight-packing on the bacteria within the clump and how this may lead to a protective effect against antibiotics.

    “Antibiotic therapy is the mainstay of treatment for tuberculosis infections, but therapeutic regimens are long and complicated, with an increasing threat of drug resistance,” says Richa Mishra, the other first author who is currently at EPFL’s Global Health Institute. “There is a recognized need for host-directed therapies or therapies that inhibit specific virulence mechanisms that can shorten and improve antibiotic therapy.”

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  • Global consensus on ethical AI use measured by researchers.

    Global consensus on ethical AI use measured by researchers.

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    Newswise — To examine the global state of AI ethics, a team of researchers from Brazil performed a systematic review and meta-analysis of global guidelines for AI use. Publishing October 13 in in the journal Patterns, the researchers found that, while most of the guidelines valued privacy, transparency, and accountability, very few valued truthfulness, intellectual property, or children’s rights. Additionally, most of the guidelines described ethical principles and values without proposing practical methods for implementing them and without pushing for legally binding regulation.

    “Establishing clear ethical guidelines and governance structures for the deployment of AI around the world is the first step to promoting trust and confidence, mitigating its risks, and ensuring that its benefits are fairly distributed,” says social scientist and co-author James William Santos of the Pontifical Catholic University of Rio Grande do Sul.

    “Previous work predominantly centered around North American and European documents, which prompted us to actively seek and include perspectives from regions such as Asia, Latin America, Africa, and beyond,” says lead author Nicholas Kluge Corrêa of the Pontifical Catholic University of Rio Grande do Sul and the University of Bonn.

    To determine whether a global consensus exists regarding the ethical development and use of AI, and to help guide such a consensus, the researchers conducted a systematic review of policy and ethical guidelines published between 2014 and 2022. From this, they identified 200 documents related to AI ethics and governance from 37 countries and six continents and written or translated into five different languages (English, Portuguese, French, German, and Spanish). These documents included recommendations, practical guides, policy frameworks, legal landmarks, and codes of conduct.

    Then, the team conducted a meta-analysis of these documents to identify the most common ethical principles, examine their global distribution, and assess biases in terms of the type of organizations or people producing these documents.

    The researchers found that the most common principles were transparency, security, justice, privacy, and accountability, which appeared in 82.5%, 78%, 75.5%, 68.5%, and 67% of the documents, respectively. The least common principles were labor rights, truthfulness, intellectual property, and children/adolescent rights, which appeared in 19.5%, 8.5%, 7%, and 6% of the documents, and the authors emphasize that these principles deserve more attention. For example, truthfulness—the idea that AI should provide truthful information—is becoming increasingly relevant with the release of generative AI technologies like ChatGPT. And since AI has the potential to displace workers and change the way we work, practical measures are to avoid mass unemployment or monopolies.

    Most (96%) of the guidelines were “normative”—describing ethical values that should be considered during AI development and use—while only 2% recommended practical methods of implementing AI ethics, and only 4.5% proposed legally binding forms of AI regulation.

    “It’s mostly voluntary commitments that say, ‘these are some principles that we hold important,’ but they lack practical implementations and legal requirements,” says Santos. “If you’re trying to build AI systems or if you’re using AI systems in your enterprise, you have to respect things like privacy and user rights, but how you do that is the gray area that does not appear in these guidelines.”

    The researchers also identified several biases in terms of where these guidelines were produced and who produced them. The researchers noted a gender disparity in terms of authorship. Though 66% of samples had no authorship information, the authors of the remaining documents more often had male names (549 = 66% male, 281 = 34% female). 

    Geographically, most of the guidelines came from countries in Western Europe (31.5%), North America (34.5%), and Asia (11.5%), while less than 4.5% of the documents originated in South America, Africa, and Oceania combined. Some of these imbalances in distribution may be due to language and public access limitations, but the team says that these results suggest that many parts of the Global South are underrepresented in the global discourse on AI ethics. In some cases, this includes countries that are heavily involved in AI research and development, such as China, whose output of AI-related research increased by over 120% between 2016 and 2019.

    “Our research demonstrates and reinforces our call for the Global South to wake up and a plea for the Global North to be ready to listen and welcome us,” says co-author Camila Galvão of the Pontifical Catholic University of Rio Grande do Sul. “We must not forget that we live in a plural, unequal, and diverse world. We must remember the voices that, until now, haven’t had the opportunity to claim their preferences, explain their contexts, and perhaps tell us something that we still don’t know.”

    As well as incorporating more voices, the researchers say that future efforts should focus on how to practically implement principles of AI ethics. “The next step is to build a bridge between abstract principles of ethics and the practical development of AI systems and applications,” says Santos.

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  • Modeling Study Indicates Potential for US to Reduce Building Emissions by 91%, Resulting in $100 Billion Annual Savings in Energy Costs

    Modeling Study Indicates Potential for US to Reduce Building Emissions by 91%, Resulting in $100 Billion Annual Savings in Energy Costs

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    Newswise — The US has committed to reaching net-zero emissions by 2050. To accomplish this goal, large cuts in emissions are necessary, especially in high-emission sectors like the building industry. In an article publishing on August 18 in the journal One Earth, a team of researchers use a computational model to analyze several scenarios of future building energy use in the US. They find that by tackling emissions on multiple fronts and placing focus on “demand-side measures” that affect how power is drawn from the grid, such as technologies like electric heat pumps and smart thermostats, the US can achieve its climate goals, decrease building emissions by 91% from their 2005 peak, and save over $100 billion each year on energy costs.

    “Meeting the US 2050 net-zero emissions target requires a rapid and cost-effective low-carbon transition across the entire energy system,” writes the team of energy technology experts based at Lawrence Berkeley National Laboratory and energy consultants. “Commercial and residential buildings are a primary source of emissions and are key to this transition.”

    In the United States, the authors cite, buildings—including both public buildings, like offices, and private buildings, like homes—contribute 35% of the country’s total greenhouse gas emissions. In 2005, the US contributed 2,327 megatons of carbon dioxide in the buildings sector, setting a record for all-time high emissions. Since then, emissions have declined by 25%, and are projected to keep declining by up to another 41% by 2050. But we will need to keep cutting emissions to reach our climate goals, assert the authors.

    For their analysis, the authorship team defines three main ways to cut building-related emissions. They argue that we should focus on making buildings use energy more efficiently, making the power grid more reliable by increasing the flexibility of how energy is managed by the grid, and utilizing low-carbon energy sources. “There are no ‘silver bullet’ solutions for building decarbonization,” write the authors. “Achieving deeper levels of emissions reductions will require a comprehensive mix of solutions addressing both the generation and end uses of energy—a true ‘all-of-the-above’ menu of solutions to decarbonize the built environment.”

    The team modeled “low,” “moderate,” and “aggressive” scenarios of this “all-of-the-above menu” to determine the degree to which we can cut emissions. They found that it’s possible to reduce building emissions by 91% compared to 2005 levels by 2050, and that demand-side measures that increase the flexibility of the power grid, like heat pumps and smart thermostats, could contribute up to 45% of these emissions cuts.

    “Flexibility will play an increasingly important role as variable renewable energy accounts for a larger share of power generation and distribution networks are challenged by growing demand for clean electricity,” write the researchers.

    However, achieving this level of emissions cuts would require the “aggressive” level of intervention from the researchers’ model, and the authors emphasize that an “unprecedented scale and speed of building technology development and deployment” would be necessary, as well as a largescale commitment to changing how we consume energy.

    “Realizing this level of change in the building sector will require a rapid and sustained increase in investment alongside policy and regulatory support,” write the authors. “We hope that this study can inform concrete policy approaches that accelerate energy system decarbonization across both demand- and supply-side technologies to fulfill ambitious targets for climate change mitigation in the US.”

     

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  • Cockatoos know to bring along multiple tools when they fish for cashews

    Cockatoos know to bring along multiple tools when they fish for cashews

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    Newswise — Goffin’s cockatoos have been added to the short list of non-human animals that use and transport toolsets. In a study publishing in the journal Current Biology on February 10, researchers show that the cockatoos carry multiple tools to their worksite when the job calls for it. This behavior has only been previously reported in chimpanzees, our closest relatives.

    Goffin’s cockatoos are small white parrots that hail from the Tanimbar Islands archipelago in Indonesia. Captive Goffin’s cockatoos use and manufacture tools, and a recent study of wild-caught cockatoos reported that they can use up to three different tools to extract seeds from a particular fruit. Up until now, though, it wasn’t clear whether the cockatoos considered these tools as a “set”; it’s possible that what may look like a toolset is instead nothing more than a chain of single tool uses, with the need for each new tool appearing to the animal as the task evolves.

    Now, a team of researchers have used controlled experiments to clarify that the cockatoos do indeed recognize when a job requires more than one tool. “With this experiment we can say that, like chimpanzees, Goffin’s cockatoos not only appear to be to using toolsets, but they know that they are using toolsets,” says first author Antonio Osuna-Mascaró, an evolutionary biologist at the University of Veterinary Medicine Vienna. “Their flexibility of behavior is stunning.”

    Osuna-Mascaró was inspired by the termite-fishing Goualougo Triangle chimpanzees of northern Congo, the only other known non-human animal to use toolsets. These chimpanzees fish for termites via a two-step process: first, they use a blunt stick to break holes in the termite mound, and then they insert a long, flexible probe to “fish” the termites out of the holes. In this study, Osuna-Mascaró’s team tasked the cockatoos with fishing for cashews instead of termites.

    To mimic the termite-fishing set-up, the researchers presented the cockatoos with a box containing a cashew behind a transparent paper membrane. To reach the cashew, the cockatoos had to punch through the membrane and then “fish” the cashew out. They were provided with a short, pointy stick for punching holes and a vertically halved plastic straw for fishing.

    Seven of the ten cockatoos tested taught themselves to extract cashews successfully by punching through the membrane, and two of the cockatoos (Figaro and Fini) completed the task within 35 seconds on their first attempt. The cockatoos don’t have an equivalent foraging behavior in the wild, so there was no chance that their tool use was based on innate behaviors, and each cockatoo used a slightly different technique.

    Next, the team tested the cockatoos’ ability to change their tool use in a flexible manner depending on the situation. To do this, they presented each cockatoo with two different types of box: one with a membrane and one without. The cockatoos were given the same two tools, but they only needed the pointy stick when a membrane was in the way. “The cockatoos had to act according to the problem; sometimes the toolset was needed, and sometimes only one tool was enough,” says Osuna-Mascaró.

    All of the cockatoos mastered the test in a very short period of time and were able to recognize when a single tool was sufficient. However, the birds engaged in an interesting behavior during this choosing phase. “When making the choice between which tool to use first, they were picking one up, releasing it, then picking up the other one, releasing it, returning to the first one, and so on,” says Osuna-Mascaró. The researchers found that when cockatoos did this switching, they performed better on the tests.

    Next, the team tested the cockatoos’ ability to transport the tools as a set on an as-needed basis. They put the cockatoos through a series of increasingly challenging trials to reach the boxes: first they had to climb a short ladder while carrying their tools; then they had to fly horizontally with them; and in the final test, they had to carry the tools while flying vertically. As before, the birds were only sometimes presented with a box with a membrane barrier, so they had to decide whether the problem required one or both tools.

    Some cockatoos learned to carry the two tools together—by inserting the short punching stick into the groove of the halved straw—when they were presented with a box that required both. This meant they only had to make one trip, albeit while carrying a heavier toolset. Most of the cockatoos transported the toolset on an as-needed basis, further indicating that they knew ahead of time when two tools were required, though some made two trips when necessary. One cockatoo, Figaro, decided not to waste time thinking and instead carried both tools in almost every trial.

    “We really did not know whether the cockatoos would transport two objects together,” says Alice Auersperg, senior author on the study and a cognitive biologist at the University of Veterinary Medicine Vienna. “It was a little bit of a gamble because I have seen birds combining objects playfully, but they very rarely transport more than one object together in their normal behavior.”

    There’s a lot more to be learned about cockatoo tool use, the researchers say. “We feel that, in terms of technical cognition and tool use, parrots have been underestimated and understudied,” says Auersperg.

    “We’ve learned how dexterous the cockatoos are when using a toolset, and we have a lot of things to follow-up on,” says Osuna-Mascaró. “The switching behavior is very interesting to us, and we are definitely going to use it to explore their decision making and their metacognition—their ability to recognize their own knowledge.”

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    This research was supported by the Vienna Science and Technology Fund and the Austrian Science Fund.

    Current Biology, Osuna-Mascaró et al. “Flexible tool set transport in Goffin’s cockatoos,” https://www.cell.com/current-biology/fulltext/S0960-9822(23)00057-X

    Current Biology (@CurrentBiology), published by Cell Press, is a bimonthly journal that features papers across all areas of biology. Current Biology strives to foster communication across fields of biology, both by publishing important findings of general interest and through highly accessible front matter for non-specialists. Visit: http://www.cell.com/current-biology. To receive Cell Press media alerts, contact [email protected].

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  • Forests face fierce threats from multiple industries, not just agricultural expansion

    Forests face fierce threats from multiple industries, not just agricultural expansion

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    Newswise — Intact forests are important climate regulators and harbors of biodiversity, but they are rapidly disappearing. Agriculture is commonly considered to be the major culprit behind forest loss, but the authors of a new paper publishing on January 20 in the journal One Earth show that agriculture isn’t solely to blame. For forest loss associated with the 2014 world economy, over 60% was related to final consumption of non-agricultural products, such as minerals, metals and wood-related goods, and the authors argue that we must consider international trade markets when designing conservation strategies.

    “Regional land use change is no longer simply driven by local demand; it is also indirectly influenced by international markets and the surging consumption of land-based products,” say the authors, led by Bin Chen, a postdoctoral fellow at Fudan University. “Countries with forest conservation goals can import finished land-based products via global supply chains, displacing land-use pressure and related eco-environmental impacts outside their own territory borders.”

    The researchers used multi-source geographic information data and economic modeling to evaluate the direct and indirect causes of intact forest landscape loss. Intact forests support more diverse species, are more resilient to natural disturbances such as wildfires, and in Africa and South America, can store more than three times the amount of carbon per hectare compared to disturbed or managed forests.

    Previous studies have focused on deforestation—the complete removal of tree cover—but focusing on intact forests instead allowed the authors to shine a spotlight on the insidious roles played by degradation and fragmentation.

     “Even the removal of narrow tracts of forests can affect overall forest structure and composition,” say the authors. “Considering the exceptional conservation value of intact forest landscapes in terms of stabilizing terrestrial carbon stocks and harboring biodiversity, intact forest landscapes loss displacement can also reflect potential indirect driving forces behind carbon emissions and biodiversity loss.”

    “It is widely thought that beef production drives deforestation in the Amazon, but it is hard for consumers to realize that the production of highly processed equipment may involve timber and metals produced at the expense of intact forest and that services provided by tertiary sectors may be supported by electricity generated from oil and gas associated with this loss” the authors say. “The more dispersed nature of intact forest loss drivers and their indirect links to individual final consumers call for stronger government engagement and supply-chain interventions.”

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  • Humans continue to evolve with the emergence of new genes

    Humans continue to evolve with the emergence of new genes

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    Newswise — Modern humans evolutionarily split from our chimpanzee ancestors nearly 7 million years ago, yet we are continuing to evolve. 155 new genes have been identified within the human lineage that spontaneously arose from tiny sections of our DNA. Some of these new genes date back to the ancient origin of mammals, with a few of these “microgenes” predicted to be associated with human-specific diseases. This work is publishing on December 20th in the journal Cell Reports.

    “This project started back in 2017 because I was interested in novel gene evolution and figuring out how these genes originate,” says first author Nikolaos Vakirlis (@vakirlis), a scientist at the Biomedical Sciences Research Center “Alexander Fleming” in Vari, Greece. “It was put on ice for a few years, until another study got published that had some very interesting data, allowing us to get started on this work.”

    Taking the previously published dataset of functionally relevant new genes, the researchers created an ancestral tree comparing humans to other vertebrate species. They tracked the relationship of these genes across evolution and found 155 that popped up from regions of unique DNA. New genes can arise from duplication events that already exist in the genome; however, these genes arose from scratch.

    “It was quite exciting to be working in something so new,” says senior author Aoife McLysaght (@aoifemcl), a scientist at Trinity College Dublin. “When you start getting into these small sizes of DNA, they’re really on the edge of what is interpretable from a genome sequence, and they’re in that zone where it’s hard to know if it is biologically meaningful.”

    Of these 155 new genes, 44 of them are associated with growth defects in cell cultures, demonstrating the importance of these genes in maintaining a healthy, living system. Since these genes are human specific, it makes direct testing difficult. Researchers must seek another way to explore what effects these new genes may have on the body. Vakirlis and his team examined patterns found within the DNA that can hint at if these genes play a role in specific diseases.

    Three of these 155 new genes have disease-associated DNA markers that point to connections with ailments such as muscular dystrophy, retinitis pigmentosa, and Alazami syndrome. Apart from disease, the researchers also found a new gene that is associated with human heart tissue. This gene emerged in human and chimp right after the split from gorilla and shows just how fast a gene can evolve to become essential for the body.

    “It will be very interesting in future studies to understand what these microgenes might do and whether they might be directly involved in any kind of disease,” says Vakirlis.

    “These genes are convenient to ignore because they’re so difficult to study, but I think it’ll be increasingly recognized that they need to be looked at and considered,” says McLysaght. “If we’re right in what we think we have here, there’s a lot more functionally relevant stuff hidden in the human genome.”

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    Financial support provided by the European Research Council and by Greece and the European Union. Aoife McLysaght was a member of the journal’s Advisory Board at the time of this article’s initial submission.

    Cell Reports, Vakirlis et al., “De novo birth of functional microproteins in the human lineage.” https://www.cell.com/cell-reports/fulltext/S2211-1247(22)01696-5 

    Cell Reports (@CellReports), published by Cell Press, is a weekly open access journal that publishes high-quality papers across the entire life sciences spectrum. The journal features reports, articles, and resources that provide new biological insights, are thought-provoking, and/or are examples of cutting-edge research. Visit: http://www.cell.com/cell-reports. To receive Cell Press media alerts, contact [email protected].

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  • Human Expansion 1,000 Years Ago Linked to Madagascar’s Loss of Large Vertebrates

    Human Expansion 1,000 Years Ago Linked to Madagascar’s Loss of Large Vertebrates

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    Newswise — The island of Madagascar—one of the last large land masses colonized by humans—sits about 250 miles (400 kilometers) off the coast of East Africa. While it’s still regarded as a place of unique biodiversity, Madagascar long ago lost all its large-bodied vertebrates, including giant lemurs, elephant birds, turtles, and hippopotami. A human genetic study reported in the journal Current Biology on November 4 links these losses in time with the first major expansion of humans on the island, around 1,000 years ago.

    “This human demographic expansion was simultaneous with a cultural and ecological transition on the island,” says Denis Pierron, French National Centre for Scientific Research (CNRS) researcher in Toulouse, France. “Around the same period, cities appeared in Madagascar and all the vertebrates of more than 10 kilograms disappeared.”

    The origins of humans in Madagascar has long been an enigma, Pierron explained. Madagascar is home to 25 million people who speak an Asian language despite the island’s proximity to East Africa. Other groups who speak similar languages live more than 4,000 miles away. The people that live on Madagascar are known to trace their roots back to two small populations: one Bantu-speaking from Africa and another Austronesian-speaking from Asia. But, beyond that, the history remained rather murky.

    To retrace the history and understand more about the origin of Malagasy people, a multi-disciplinary consortium launched in 2007 a project known as Madagascar Genetic and Ethnolinguistic (MAGE). Over a 10-year period, Malagasy and international researchers visited more than 250 villages across the country to sample the cultural and genetic human diversity.

    In the new study, Pierron and his colleagues took a close look at the human genetic evidence. More specifically, they closely studied how various segments of human chromosomes were shared together with local ancestry information and computer-simulated genetic data. Together, they’ve inferred that the Malagasy ancestral Asian population was isolated on the island for more than 1,000 years with an effective population size of just a few hundred individuals.

    Their isolation ended about 1,000 years ago when a small group of Bantu-speaking African people came to Madagascar. Afterwards, the population continued to expand rapidly over generations. The growing human population led to extensive changes to the Madagascar landscape and the loss of all large-bodied vertebrates that once lived there, they suggest.

    The findings have important implications that may now be applied to studies of other human populations. For instance, it shows it’s possible to untangle the demographic history of ancient populations even well after two or more groups have mixed, by using genetic data and computer simulations to test the likelihood of different scenarios. The findings also offer new insights into how past changes in human populations led to changes in whole ecosystems.

    “Our study supports the theory that it was not directly the arrival of humans on the island that caused the disappearance of the megafauna, but rather a change in lifestyle that caused both a human population expansion and a reduction in biodiversity in Madagascar,” Pierron says.

    While these efforts have led to much better understanding of Madagascar’s history, many intriguing questions remain. For instance, Pierron asks, “If the ancestral Asian population was isolated for more than a millennium before mixing with the African population, where was this population? Already in Madagascar or in Asia? Why did the Asian population isolate itself over 2,000 years ago? Around 1,000 years ago, what triggered the observed cultural and demographic transition?” 

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    This work was supported by the Région Aquitaine “Project MAGE” (Madagascar Genétique et Ethnolinguistique) and the French National Research Agency (ANR) Grants “MADEOGEN.”

    Current Biology, Alva et al. “The loss of biodiversity in Madagascar is contemporaneous with major demographic events.” https://www.cell.com/current-biology/fulltext/S0960-9822(22)01602-5

    Current Biology (@CurrentBiology), published by Cell Press, is a bimonthly journal that features papers across all areas of biology. Current Biology strives to foster communication across fields of biology, both by publishing important findings of general interest and through highly accessible front matter for non-specialists. Visit http://www.cell.com/current-biology. 

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  • Scientists Find First Evidence That Marine Conservation Mitigates Climate Change

    Scientists Find First Evidence That Marine Conservation Mitigates Climate Change

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    Newswise — Marine protected areas act as a safeguard for oceans, seas, and estuaries. These zones help to preserve the plants and animals that call these waters home, but the benefits of protected areas extend far beyond their boundaries. In a review publishing October 21 in the journal One Earth, a team of researchers explain how marine protected areas help to sequester carbon and foster ecological and social adaption to climate change.

    “Marine protected areas are increasingly being promoted as an ocean-based climate solution. Yet such claims remain controversial due to the diffuse and poorly synthesized literature on climate benefits of marine protected areas,” write the authors. “To address this knowledge gap, we conducted a systematic literature review of 22,403 publications spanning 241 marine protected areas.”

    The authors found that carbon sequestration in marine protected areas increased significantly in seagrass areas, mangroves, and in areas where sediment wasn’t trawled. “Partial or full degradation of mangroves and seagrass both resulted in similar decreases of sequestered carbon, indicating that even low levels of human impact result in important carbon emissions,” they write.

    In addition to boosting carbon sequestration, preserved areas were more biodiverse, had increased species richness, and showed benefits for humans, too. Marine protected areas had greater food security, and fish stocks in waters adjacent to these protected areas swelled. The authors note that the mitigation and adaptation benefits of these protected areas were only achieved under high levels of protection, and that benefits increased the longer an area had been protected.

    “Across all four pathways analyzed, only full and high levels of protection resulted in mitigation or adaptation benefits,” they write. “In contrast, low levels of protection generated no benefits. Furthermore, increases in species richness and in fishers’ income only occurred for fully protected areas, where no fishing is allowed.”

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    One Earth, Jacquemont et al. “Ocean conservation boosts climate change mitigation and adaptation” https://www.cell.com/one-earth/fulltext/S2590-3322(22)00480-8

    One Earth (@OneEarth_CP), published by Cell Press, is a monthly journal that features papers from the fields of natural, social, and applied sciences. One Earth is the home for high-quality research that seeks to understand and address today’s environmental Grand Challenges, publishing across the spectrum of environmental change and sustainability science. A sister journal to Cell, Chem, and Joule, One Earth aspires to break down barriers between disciplines and stimulate the cross-pollination of ideas with a platform that unites communities, fosters dialogue, and encourages transformative research. Visit http://www.cell.com/one-earth. To receive Cell Press media alerts, contact [email protected].

    For the latest sustainability research and ideas from Cell Press follow @CellPressSust on Twitter.

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  • Viral infections are less frequent but more severe in people with Down syndrome due to oscillating immune response

    Viral infections are less frequent but more severe in people with Down syndrome due to oscillating immune response

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    Newswise — Individuals with Down syndrome have less-frequent viral infections, but when present, these infections lead to more severe disease. New findings publishing on October 14 in the journal Immunity show that this is caused by increased expression of an antiviral cytokine type I interferon (IFN-I), which is partially coded for by chromosome 21. Elevated IFN-I levels lead to hyperactivity of the immune response initially, but the body overcorrects for this to reduce inflammation, leading to increased vulnerability later in the viral attack.

    “Usually too much inflammation means autoimmune disease, and immune suppression usually means susceptibility to infections,” says senior study author Dusan Bogunovic of the Icahn School of Medicine at Mount Sinai. “What is unusual is that individuals with Down syndrome are both inflamed and immunosuppressed, a paradox of sorts. Here, we discovered how this is possible.”

    Down syndrome is typically caused by triplication of chromosome 21. This syndrome affects multiple organ systems, causing a mixed clinical presentation that includes intellectual disability, developmental delays, congenital heart and gastrointestinal abnormalities, and Alzheimer’s disease in older individuals.

    Recently, it has become clear that atypical antiviral responses are another important feature of Down syndrome. Increased rates of hospitalization of people with Down syndrome have been documented for influenza A virus, respiratory syncytial virus, and severe acute respiratory syndrome due to coronavirus (SARS-CoV-2) infections.

    While people with Down syndrome show clear signs of immune disturbance, it has yet to be elucidated how a supernumerary chromosome 21 leads to dysregulation of viral defenses. To address this knowledge gap, the researchers compared fibroblasts and white blood cells derived from individuals with and without Down syndrome, at both the mRNA and protein levels. They focused on the potent antiviral cytokine IFN-I receptor subunits IFNAR1 and IFNAR2, which are located on chromosome 21.

    The researchers found that increased IFNAR2 expression was sufficient for the hypersensitivity to IFN-I observed in Down syndrome, independent of trisomy 21. But subsequently, the hyper-active IFN-I signaling cascade triggered excessive negative feedback via a protein called USP18, which is a potent IFNAR negative regulator. This process, in turn, suppressed further responses to IFN-I and antiviral responses. Taken together, the findings unveil oscillations of hyper- and hypo-responses to IFN-I in Down syndrome, predisposing to both lower incidence of viral disease and increased infection-related morbidity and mortality.

    “We have a lot more to do to completely understand the complexities of the immune system in Down syndrome,” says first author Louise Malle of the Icahn School of Medicine at Mount Sinai. “We have here, in part, explained the susceptibility to severe viral disease, but this is only the tip of the iceberg.”

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