ReportWire

Tag: Marine Science

  • OceanGate Faces Federal Investigation a Year After the Titan Submersible Implosion

    OceanGate Faces Federal Investigation a Year After the Titan Submersible Implosion

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    The apparent success of the leaseback arrangement might explain how Rush was able to attract what was OceanGate’s largest ever investment in 2020, at a time when the company was working on the expensive task of replacing the Titan’s first hull that had cracked during testing. The $18 million in equity funding allowed OceanGate to rebuild the Titan and move forward with its first Titanic expedition in 2021. Around this time, documents indicate that OceanGate may have had more control in the taken-over ownership of Cyclops 2 LLC.

    But by 2023, OceanGate seemed to be on a much shakier financial footing. Several witnesses at the Coast Guard hearings testified to what they perceived to be OceanGate’s financial difficulties in the run-up to the final Titanic expedition, including Rush foregoing his salary and occasionally loaning the company money from his personal funds.

    Demand for the $250,000 Titanic dives appeared to be tailing off. As late as May 2023, one of OceanGate’s affiliate sellers was advertising that there were still “some very limited dates and spots available at a 40 percent discount” for that summer’s expeditions. This has not been reported previously.

    If the federal investigation results in any criminal charges, they would proceed alongside a civil lawsuit currently in a federal court in Washington state. In that case, the family of famed Titanic explorer Paul-Henri Nargeolet is seeking $50 million for his death aboard the Titan, with the lawsuit naming as defendants OceanGate, Rush’s estate, and a number of other individuals and companies connected to the ill-fated submersible. Rush’s estate recently filed a motion to dismiss the complaint against it, stating: “As Rush’s employer, OceanGate is liable for Rush’s alleged negligence.”

    Maritime lawyer Alton Hall is skeptical that Nargeolet’s family will recover anything close to the $50 million they are seeking. A 1920 law, the Death on the High Seas Act, generally limits damages to pecuniary losses, such as future earnings. One exception would be if Nargeolet and his fellow Titan passengers, whom OceanGate dubbed “mission specialists,” qualified as seamen under another piece of legislation called the Jones Act. “There are literally books and books written on who is and who isn’t a Jones Act seaman,” says Hall. The passengers who died onboard the Titan “are not Jones Act seamen,” he believes.

    An unknown question in these cases—and other cases that might be brought by the families of the two billionaires who also died on the Titan—is who might face legal consequences. The civil case against OceanGate and Rush’s estate also names as defendants OceanGate’s original director of engineering, Tony Nissen, and three companies that manufactured the Titan’s hull and viewport. However, multiple witnesses at the Coast Guard hearings testified to Stockton Rush having the final say in many commercial, engineering, and operational decisions, and his company is likely all but bankrupt. In the end, there might be little to salvage from the wreckage of OceanGate.

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    Mark Harris

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  • The Sea Is Swallowing This Mexican Town

    The Sea Is Swallowing This Mexican Town

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    “That’s why my husband hardly ever goes out anymore. You have to go far out to sea,” says Florencia Hernandez, 81, grandmother of Otsoa and Ramón, known locally as Pola. In a wheelchair surrounded by memories—black and white portraits, lead hooks, the fishing line she holds in her hands—she is the longest-lived witness of the transformation that her land has undergone. She learned the fishing trade in her youth.

    “My father taught me. Like my grandfather, he was a fisherman. He had a little wooden boat, and he took me when I was a child,” says Hernandez while showing a photo album. “Later, I fished with my brother Salvador. I was the one who grabbed the motor. We would go out at night. When I got married, I accompanied my husband. I would get up very early in the morning, leave the clothes washed and laid out for when we returned from the day’s work. In a short time, we would fill baskets with fish that we would sell in the afternoon,” she says.

    An abandoned boat in the fishing community of Las Barrancas, Mexico.Photograph: Seila Montes

    Hernandez and her husband raised their children with what they earned from the sea. “The sea that has given me everything and now takes everything away,” she says with a broken voice. In Las Barrancas they live every day with the fear of the arrival of a hurricane like Roxanne, which landed in 1995. “I was only 8 years old but I remember it very well. That one hit very hard. It took a lot of houses,” says Ramón.

    Climate Change and Poorly Planned Projects

    Between the storm surges, the sea level continues to gradually rise. In the waters of the Gulf of Mexico, that increase is about three times faster than the global average, according to a 2023 study published in Nature. “This could be due to the loss of important habitats, such as seagrasses and reefs, natural barriers that protect the coast,” says Patricia Moreno-Casasola, a biologist at the Institute of Ecology.

    “Here it’s already taken 100 meters of beach,” says Otsoa. “The impact has not only been environmental and on fishing, on which we live, but it has also had a great social impact. The beach was our means of communication with the other neighboring communities,” explains the fisherwoman. The tourism that her town used to attract has also fallen off.

    “My mother had a little food stand by the beach that was crowded at Easter, a business that sold snacks. We lived on that income almost all year round,” Ramón says. Even horse races were organized there on the beach.”

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    Andrea J. Arratibel

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  • Some mosquitoes like it hot

    Some mosquitoes like it hot

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    Newswise — Certain populations of mosquitoes are more heat tolerant and better equipped to survive heat waves than others, according to new research from Washington University in St. Louis.

    This is bad news in a world where vector-borne diseases are an increasingly global health concern. Most models that scientists use to estimate vector-borne disease risk currently assume that mosquito heat tolerances do not vary. As a result, these models may underestimate mosquitoes’ ability to spread diseases in a warming world.

    Researchers led by Katie M. Westby, a senior scientist at Tyson Research Center, Washington University’s environmental field station, conducted a new study that measured the critical thermal maximum (CTmax), an organism’s upper thermal tolerance limit, of eight populations of the globally invasive tiger mosquito, Aedes albopictus. The tiger mosquito is a known vector for many viruses including West Nile, chikungunya and dengue.

    “We found significant differences across populations for both adults and larvae, and these differences were more pronounced for adults,” Westby said. The new study is published Jan. 8 in Frontiers in Ecology and Evolution.

    Westby’s team sampled mosquitoes from eight different populations spanning four climate zones across the eastern United States, including mosquitoes from locations in New Orleans; St. Augustine, Fla.; Huntsville, Ala.; Stillwater, Okla.; St. Louis; Urbana, Ill.; College Park, Md.; and Allegheny County, Pa.

    The scientists collected eggs in the wild and raised larvae from the different geographic locations to adult stages in the lab, tending the mosquito populations separately as they continued to breed and grow. The scientists then used adults and larvae from subsequent generations of these captive-raised mosquitoes in trials to determine CTmax values, ramping up air and water temperatures at a rate of 1 degree Celsius per minute using established research protocols.

    The team then tested the relationship between climatic variables measured near each population source and the CTmax of adults and larvae. The scientists found significant differences among the mosquito populations.

    The differences did not appear to follow a simple latitudinal or temperature-dependent pattern, but there were some important trends. Mosquito populations from locations with higher precipitation had higher CTmax values. Overall, the results reveal that mean and maximum seasonal temperatures, relative humidity and annual precipitation may all be important climatic factors in determining CTmax.

    “Larvae had significantly higher thermal limits than adults, and this likely results from different selection pressures for terrestrial adults and aquatic larvae,” said Benjamin Orlinick, first author of the paper and a former undergraduate research fellow at Tyson Research Center. “It appears that adult Ae. albopictus are experiencing temperatures closer to their CTmax than larvae, possibly explaining why there are more differences among adult populations.”

    “The overall trend is for increased heat tolerance with increasing precipitation,” Westby said. “It could be that wetter climates allow mosquitoes to endure hotter temperatures due to decreases in desiccation, as humidity and temperature are known to interact and influence mosquito survival.”

    Little is known about how different vector populations, like those of this kind of mosquito, are adapted to their local climate, nor the potential for vectors to adapt to a rapidly changing climate. This study is one of the few to consider the upper limits of survivability in high temperatures — akin to heat waves — as opposed to the limits imposed by cold winters.

    “Standing genetic variation in heat tolerance is necessary for organisms to adapt to higher temperatures,” Westby said. “That’s why it was important for us to experimentally determine if this mosquito exhibits variation before we can begin to test how, or if, it will adapt to a warmer world.”

    Future research in the lab aims to determine the upper limits that mosquitoes will seek out hosts for blood meals in the field, where they spend the hottest parts of the day when temperatures get above those thresholds, and if they are already adapting to higher temperatures. “Determining this is key to understanding how climate change will impact disease transmission in the real world,” Westby said. “Mosquitoes in the wild experience fluctuating daily temperatures and humidity that we cannot fully replicate in the lab.”

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    Washington University in St. Louis

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  • First Study of its Kind Reveals Impact of River Sediment on US Coastline

    First Study of its Kind Reveals Impact of River Sediment on US Coastline

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    Newswise — As sea level continues to rise, threatening ecosystems, communities and infrastructure, experts are searching for ways to better understand how coastal environments may change in the future. A new research breakthrough published in Science reveals a novel way to study these changes by measuring how much sediment from the nation’s rivers makes it to the coastline. 

     

    Measuring, Mapping and Modeling 

    After testing many approaches in many different watersheds, UNCW Department of Earth and Ocean Sciences Professor Joanne Halls and co-authors Scott Ensign (Stroud Water Research Center) and Erin Peck (Northeast Climate Adaptation Science Center and USGS Woods Hole Coastal and Marine Science Center) developed a solution to measure the rate of river sediment accumulation across all watersheds of the contiguous United States.

    Using her expertise in Geographic Information Science (GIS), Halls developed a new web application called Sediment Pancakes. The app uses publicly available geospatial data to create digital models and interactive maps of the entire continental U.S. coast, including 4,972 rivers and streams. This is the first continent-wide examination of its kind. 

    “We tend to know much more about our large rivers and very little about the amount of river sediment in the smaller creeks and tributaries, even though these smaller systems are the majority of the landscape,” Halls said. “To our knowledge, this new web application is the only tool that provides local estimates of riverine sediment for all rivers of the contiguous U.S.”  

    The published paper, “Watershed Sediment Cannot Offset Sea Level Rise in Most US Tidal Wetlands,” concluded that 72% of all rivers do not provide adequate sediment, on an annual basis, to keep up with current estimates of sea level rise. In other words, river-borne sediment alone is insufficient to provide the elevation gain needed to offset increasing sea levels found in tidal wetlands like marshes, swamps and bogs. 

     

    Planning for the Future 

    As many local government agencies are building coastal resilience plans, and researchers nationwide are designing monitoring strategies to study and protect the coastal environments, the Sediment Pancakes app is a tool they can use to inform their planning.  

    “The more we leverage the enormous amount of map data toward principles of ‘smart growth,’ the better we can make our local communities,” Halls said. “My goal is to deliver map tools that assist local residents and planners so that we empower people to be engaged, exchange ideas in a meaningful and equitable way, and inspire students to be creative problem-solvers.” 

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    University of North Carolina Wilmington

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  • Separating out signals recorded at the seafloor

    Separating out signals recorded at the seafloor

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    Newswise — Blame it on plate tectonics. The deep ocean is never preserved, but instead is lost to time as the seafloor is subducted. Geologists are mostly left with shallower rocks from closer to the shoreline to inform their studies of Earth history.

    “We have only a good record of the deep ocean for the last ~180 million years,” said David Fike, the Glassberg/Greensfelder Distinguished University Professor of Earth, Environmental, and Planetary Sciences in Arts & Sciences at Washington University in St. Louis. “Everything else is just shallow-water deposits. So it’s really important to understand the bias that might be present when we look at shallow-water deposits.”

    One of the ways that scientists like Fike use deposits from the seafloor is to reconstruct timelines of past ecological and environmental change. Researchers are keenly interested in how and when oxygen began to build up in the oceans and atmosphere, making Earth more hospitable to life as we know it.

    For decades they have relied on pyrite, the iron-sulfide mineral known as “fool’s gold,” as a sensitive recorder of conditions in the marine environment where it is formed. By measuring the bulk isotopic composition of sulfur in pyrite samples — the relative abundance of sulfur atoms with slightly different mass — scientists have tried to better understand ancient microbial activity and interpret global chemical cycles.

    But the outlook for pyrite is not so shiny anymore. In a pair of companion papers published Nov. 24 in the journal Science, Fike and his collaborators show that variations in pyrite sulfur isotopes may not represent the global processes that have made them such popular targets of analysis.

    Instead, Fike’s research demonstrates that pyritte responds predominantly to local processes that should not be taken as representative of the whole ocean. A new microanalysis approach developed at Washington University helped the researchers to separate out signals in pyrite that reveal the relative influence of microbes and that of local climate.

    For the first study, Fike worked with Roger Bryant, who completed his graduate studies at Washington University, to examine the grain-level distribution of pyrite sulfur isotope compositions in a sample of recent glacial-interglacial sediments. They developed and used a cutting-edge analytical technique with the secondary-ion mass spectrometer (SIMS) in Fike’s laboratory.

    “We analyzed every individual pyrite crystal that we could find and got isotopic values for each one,” Fike said. By considering the distribution of results from individual grains, rather than the average (or bulk) results, the scientists showed that it is possible to tease apart the role of the physical properties of the depositional environment, like the sedimentation rate and the porosity of the sediments, from the microbial activity in the seabed.

    “We found that even when bulk pyrite sulfur isotopes changed a lot between glacials and interglacials, the minima of our single grain pyrite distributions remained broadly constant,” Bryant said. “This told us that microbial activity did not drive the changes in bulk pyrite sulfur isotopes and refuted one of our major hypotheses.”

    “Using this framework, we’re able to go in and look at the separate roles of microbes and sediments in driving the signals,” Fike said. “That to me represents a huge step forward in being able to interpret what is recorded in these signals.”

    In the second paper, led by Itay Halevy of the Weizmann Institute of Science and co-authored by Fike and Bryant, the scientists developed and explored a computer model of marine sediments, complete with mathematical representations of the microorganisms that degrade organic matter and turn sulfate into sulfide and the processes that trap that sulfide in pyrite.

    “We found that variations in the isotopic composition of pyrite are mostly a function of the depositional environment in which the pyrite formed,” Halevy said. The new model shows that a range of parameters of the sedimentary environment affect the balance between sulfate and sulfide consumption and resupply, and that this balance is the major determinant of the sulfur isotope composition of pyrite.

    “The rate of sediment deposition on the seafloor, the proportion of organic matter in that sediment, the proportion of reactive iron particles, the density of packing of the sediment as it settles to the seafloor — all of these properties affect the isotopic composition of pyrite in ways that we can now understand,” he said.

    Importantly, none of these properties of the sedimentary environment are strongly linked to the global sulfur cycle, to the oxidation state of the global ocean, or essentially any other property that researchers have traditionally used pyrite sulfur isotopes to reconstruct, the scientists said.

    “The really exciting aspect of this new work is that it gives us a predictive model for how we think other pyrite records should behave,” Fike said. “For example, if we can interpret other records — and better understand that they are driven by things like local changes in sedimentation, rather than global parameters about ocean oxygen state or microbial activity — then we can try to use this data to refine our understanding of sea level change in the past.”

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    Washington University in St. Louis

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  • AI discovers formula for anticipating giant waves.

    AI discovers formula for anticipating giant waves.

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    Newswise — Long considered myth, freakishly large rogue waves are very real and can split apart ships and even damage oil rigs. Using 700 years’ worth of wave data from more than a billion waves, scientists at the University of Copenhagen and University of Victoria have used artificial intelligence to find a formula for how to predict the occurrence of these maritime monsters. The new knowledge can make shipping safer.

    EMBARGOED CONTENT UNTIL MONDAY 20 NOVEMBER 2023 3 PM US EASTERN TIME
    Stories about monster waves, called rogue waves, have been the lore of sailors for centuries. But when a 26-metre-high rogue wave slammed into the Norwegian oil platform Draupner in 1995, digital instruments were there to capture and measure the North Sea monster. It was the first time that a rogue had been measured and provided scientific evidence that abnormal ocean waves really do exist.

    Since then, these extreme waves have been the subject of much study. And now, researchers from the University of Copenhagen’s Niels Bohr Institute have used AI methods to discover a mathematical model that provides a recipe for how – and not least when – rogue waves can occur.

    With the help of enormous amounts of big data about ocean movements, researchers can predict the likelihood of being struck by a monster wave at sea at any given time.

    “Basically, it is just very bad luck when one of these giant waves hits. They are caused by a combination of many factors that, until now, have not been combined into a single risk estimate. In the study, we mapped the causal variables that create rogue waves and used artificial intelligence to gather them in a model which can calculate the probability of rogue wave formation,” says Dion Häfner.

    Häfner is a former PhD student at the Niels Bohr Institute and first author of the scientific study, which has just been published in the prestigious journal Proceedings of the National Academy of Sciences (PNAS). 

    Rogue waves happen every day

    In their model, the researchers combined available data on ocean movements and the sea state, as well as water depths and bathymetric information. Most importantly, wave data was collected from buoys in 158 different locations around US coasts and overseas territories that collect data 24 hours a day. When combined, this data – from more than a billion waves – contains 700 years’ worth of wave height and sea state information.

    The researchers analyzed the many types of data to find the causes of rogue waves, defined as being waves that are at least twice as high as the surrounding waves – including extreme rogue waves that can be over 20 meters high. With machine learning, they transformed it all into an algorithm that was then applied to their dataset.

    “Our analysis demonstrates that abnormal waves occur all the time. In fact, we registered 100,000 waves in our dataset that can be defined as rogue waves. This is equivalent around 1 monster wave occurring every day at any random location in the ocean. However, they aren’t all monster waves of extreme size,” explains Johannes Gemmrich, the study’s second author.

    Artificial intelligence as a scientist

    In the study, the researchers were helped by artificial intelligence. They used several AI methods, including symbolic regression which gives an equation as output, rather than just returning a single prediction as traditional AI methods do.

    By examining more than 1 billion waves, the researchers’ algorithm has analyzed its own way into finding the causes of rogue waves and condensed it into equation that describes the recipe for a rogue wave. The AI learns the causality of the problem and communicates that causality to humans in the form of an equation that researchers can analyze and incorporate into their future research.

    “Over decades, Tycho Brahe collected astronomical observations from which Kepler, with lots of trial and error, was able to extract Kepler’s Laws. Dion used machines to do with waves what Kepler did with planets. For me, it is still shocking that something like this is possible,” says Markus Jochum.

    Phenomenon known since the 1700s

    The new study also breaks with the common perception of what causes rogue waves. Until now, it was believed that the most common cause of a rogue wave was when one wave briefly combined with another and stole its energy, causing one big wave to move on.

    However, the researchers establish that the most dominant factor in the materialization of these freak waves is what is known as “linear superposition”. The phenomenon, known about since the 1700s, occurs when two wave systems cross over each other and reinforce one another for a brief period of time.

    “If two wave systems meet at sea in a way that increases the chance to generate high crests followed by deep troughs, the risk of extremely large waves arises. This is knowledge that has been around for 300 years and which we are now supporting with data,” says Dion Häfner. 

    Safer shipping

    The researchers’ algorithm is good news for the shipping industry, which at any given time has roughly 50,000 cargo ships sailing around the planet. Indeed, with the help of the algorithm, it will be possible to predict when this “perfect” combination of factors is present to elevate the risk of a monster wave that could pose a danger for anyone at sea.

    “As shipping companies plan their routes well in advance, they can use our algorithm to get a risk assessment of whether there is a chance of encountering dangerous rogue waves along the way. Based on this, they can choose alternative routes,” says Dion Häfner.

    Both the algorithm and research are publicly available, as are the weather and wave data deployed by the researchers. Therefore, Dion Häfner says that interested parties, such as public authorities and weather services, can easily begin calculating the probability of rogue waves. And unlike many other models created using artificial intelligence, all of the intermediate calculations in the researchers’ algorithm are transparent.

    “AI and machine learning are typically black boxes that don’t increase human understanding. But in this study, Dion used AI methods to transform an enormous database of wave observations into a new equation for the probability of rogue waves, which can be easily understood by people and related to the laws of physics,” concludes Professor Markus Jochum, Dion’s thesis supervisor and co-author.

    Links:

    Read the scientific paper “Machine-Guided Discovery of a Real-World Rogue Wave Model” published in PNAS: https://www.pnas.org/cgi/doi/10.1073/pnas.2306275120

    Read the Wikipedia-list of registered rogue waves: https://en.wikipedia.org/wiki/List_of_rogue_waves

    Dion Häfner’s research continues at Pasteur Labs.

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    University of Copenhagen, Faculty of Science

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  • Mosasaurs had discriminating taste, palaeo-CSI finds

    Mosasaurs had discriminating taste, palaeo-CSI finds

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    Joint press release Utrecht University and Natural History Museum Maastricht

    Newswise — The cradle of palaeontology – the study of fossil remains of animals and plants – lies in the Maastricht limestones, where the first Mosasaurus was discovered in 1766. The Dutch-Belgian border area around the Limburg capital is one of the best-explored areas in the world where Cretaceous rocks are concerned, the era that came to an abrupt end 66 million years ago. New data can now be added to all previous knowledge: the Maastricht mosasaurs turned out to be quite picky in their choice of diet. This is the conclusion of researchers from Utrecht University and the Natural History Museum Maastricht. In collaboration with English colleagues from the University of Leicester, they were the first in the world to study the wear marks on mosasaur teeth.

    “We were curious whether different species of mosasaurs around Maastricht were really getting in each other’s way in their choice of food, or whether this was not so much of a problem,” explains Dr Femke Holwerda, palaeontologist at the Utrecht University Faculty of Geosciences. In the absence of data on stomach contents of the Maastricht monitor lizards, the researchers therefore looked at minute scratches on the teeth of these animals from southern Limburg (the Netherlands) and in the vicinity of Eben-Emael (province of Liège, Belgium).

    Seafood banquet

    “It seems that the various species of mosasaur reveal differences in diet. We noted these differences mainly between the smaller species – by mosasaur standards – of about three to seven metres in overall size, and the larger ones, eight to fifteen metres in length.” But there were also some differences between the larger species. “Prognathodon in particular, with its large cone-shaped teeth, appears to have had a surprising amount of shellfish in its diet, so it apparently loved its seafood buffet. Another species, Plioplatecarpus, with narrow pointed teeth, showed a striking number of signs of wear. Perhaps this species was also fond of fish with strongly scaled bodies.”

    First

    The researchers first made casts of the teeth in silicone rubber and put them in the 3D scanner. “This technique had already been used in dinosaurs, but we were the first to look at the teeth of mosasaurs in the same way,” explains fellow palaeontologist Anne Schulp, also affiliated with Utrecht University.

    Diversity

    With this research, some missing pieces of the puzzle from the long-gone latest Cretaceous world are found. “We wish to understand diversity better,” says Schulp. “And that is made easier for us because the animals studied all come from the same rocks, and therefore the same period. So instead of describing just one species, we look at the ecosystem as a whole.”

    Soft limestone

    The limestone deposits around Maastricht are a goldmine for palaeontologists. Schulp: “Nowhere else in the world is the habitat of mosasaurus as well preserved as here. You can find them in very soft limestone, so wear and tear of the teeth from other causes may be ruled out.”

    Attraction

    Of course, such an abundance of potential finds also exerts a great attraction on amateur palaeontologists. “There’s nothing wrong with that,” emphasises John Jagt, curator at the Natural History Museum Maastricht. “Amateur literally means ‘enthusiast’ and thanks to 250 years of intensive research by these enthusiasts, we have learnt a lot about mosasaurs and other extinct life forms. A museum like ours benefits greatly from this. What also helps is that this kind of amateur science is stimulated in the Netherlands: it is simply allowed by law. That’s not the case everywhere.”

    Article

    Femke M. Holwerda, Jordan Bestwick, Mark A. Purnell, John W.M. Jagt, Anne S. Schulp, ‘Three-dimensional dental microwear in type-Maastrichtian mosasaur teeth (Reptilia, Squamata)’, Scientific Reports, https://doi.org/10.1038/s41598-023-42369-7

     

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    Universiteit Utrecht, Faculteit Geowetenschappen

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  • FSU-led research shows shifting nesting timing not enough to prevent fewer sea turtle hatchlings

    FSU-led research shows shifting nesting timing not enough to prevent fewer sea turtle hatchlings

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    By: Bill Wellock | Published: | 8:20 am | SHARE: Tweet

    Newswise — New research led by a Florida State University professor shows that potential adaptive responses by sea turtles, such as shifting the timing of when they nest, may not be enough to counteract the projected impacts from climate change on hatchling production.

    Warmer temperatures cause lower hatchling success and a greater percentage of female turtles, both of which can disrupt the viability of a species. Sand temperatures at sea turtle nesting sites globally are projected to increase by about 0.6 degrees Celsius to about 4.2 degrees Celsius by 2100.

    To examine how sea turtles might cope with higher temperatures, researchers with the study, led by Department of Earth, Ocean and Atmospheric Science Associate Professor Mariana Fuentes, gathered data from 24 nesting sites across the world used by four species of sea turtles: green, loggerhead, hawksbill and olive ridley turtles.

    They used their data to predict how turtles might shift the timing of nesting and what hatchling success they might expect. The research was published today in Global Change Biology.

    “We have already observed that sea turtles are nesting earlier to align with optimal environmental conditions,” Fuentes said. “Sea turtles in the past have adapted to climate changes by changing the timing of their nesting or the distribution of their nesting sites, but we have found that even if they do change the timing of their nesting, that’s not going to be sufficient to maintain the temperatures of current nesting grounds.”

    To maintain incubation temperatures in the sites the researchers examined, sea turtles will have to nest between 20 to 191 days earlier, or 54 to 180 days later. But in about half the sites, median incubation temperature will always be warmer than the 75th percentile of current ranges.

    Turtles nesting further from the equator will be more able to counteract the impacts of warming. Those that nest closer to the equator will be most affected.

    Because temperature is so important to sea turtle egg incubation, scientists have long studied them for insight into how wildlife might adapt as temperatures rise. Different sea turtle species have existed for millions of years and adapted to previous changes in the Earths’ climate, but the rate of change is much faster now. Researchers did not examine population viability in this study, but if fewer hatchlings are being produced, in 100 years there will be some locations that have lower hatchling productivity.

    “Skeptics may say that sea turtles have been around for a long time and have adapted, but we’re showing that the adaptations that they might undertake are not going to be sufficient to counteract projected impacts,” Fuentes said.

    The study involved 52 collaborators from universities in the U.S., Mexico, Qatar, France, Australia, Turkey, Cyprus, Brazil, India, Malaysia, Guinea-Bissau, Indonesia, South Africa, Spain, French Polynesia, El Salvador and the United Kingdom. The research was supported by the National Science Foundation and by several other institutions that funded the field component of the work.

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    Florida State University

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  • Underwater robot finds new circulation pattern in Antarctic ice shelf

    Underwater robot finds new circulation pattern in Antarctic ice shelf

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    Newswise — ITHACA, N.Y. – More than merely cracks in the ice, crevasses play an important role in circulating seawater beneath Antarctic ice shelves, potentially influencing their stability, finds Cornell University-led research based on a first-of-its-kind exploration by an underwater robot.

    The remotely operated Icefin robot’s climb up and down a crevasse in the base of the Ross Ice Shelf produced the first 3D measurements of ocean conditions near where it meets the coastline, a critical juncture known as the grounding zone.

    The robotic survey revealed a new circulation pattern – a jet funneling water sideways through the crevasse – in addition to rising and sinking currents, and diverse ice formations shaped by shifting flows and temperatures. Those details will improve modeling of ice shelf melting and freezing rates at grounding zones, where few direct observations exist, and of their potential contribution to global sea-level rise.

    “Crevasses move water along the coastline of an ice shelf to an extent previously unknown, and in a way models did not predict,” said Peter Washam, a polar oceanographer and research scientist at Cornell University. “The ocean takes advantage of these features, and you can ventilate the ice shelf cavity through them.”

    Washam is the lead author of “Direct Observations of Melting, Freezing and Ocean Circulation in an Ice Shelf Basal Crevasse,” published in Science Advances.

    The scientists in late 2019 deployed the Icefin vehicle – roughly 12 feet long and less than 10 inches around – on a tether down a 1,900-foot borehole drilled with hot water, near where Antarctica’s largest ice shelf meets the Kamb Ice Stream. Such so-called grounding zones are key to controlling the balance of ice sheets, and the places where changing ocean conditions can have the most impact.

    On the team’s last of three dives, Matthew Meister, a senior research engineer, drove Icefin into one of five crevasses found near the borehole. Equipped with thrusters, cameras, sonar and sensors for measuring water temperature, pressure and salinity, the vehicle climbed nearly 150 feet up one slope and descended the other.

    The survey detailed changing ice patterns as the crevasse narrowed, with scalloped indentations giving way to vertical runnels, then green-tinted marine ice and stalactites. Melting at the crevasse base and salt rejection from freezing near the top moved water up and down around the horizontal jet, driving uneven melting and freezing on the two sides, with more melting along the lower downstream wall.

    “Each feature reveals a different type of circulation or relationship of the ocean temperature to freezing,” Washam said. “Seeing so many different features within a crevasse, so many changes in the circulation, was surprising.”

    The researchers said the findings highlight crevasses’ potential to transport changing ocean conditions – warmer or colder – through an ice shelf’s most vulnerable region.

    “If water heats up or cools off, it can move around in the back of the ice shelf quite vigorously, and crevasses are one of the means by which that happens,” Washam said. “When it comes to projecting sea-level rise, that’s important to have in the models.”

    The research was funded by Project RISE UP (Ross Ice Shelf and Europa Underwater Probe), part of NASA’s Planetary Science and Technology from Analog Research program, with logistical support provided by the National Science Foundation through the U.S. Antarctic Program. It was facilitated by the New Zealand Antarctic Research Institute, Aotearoa New Zealand Antarctic Science Platform and the Victoria University of Wellington Hot Water Drilling initiative.

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    Cornell University

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  • Climate elevates toxin risk in Northern US lakes.

    Climate elevates toxin risk in Northern US lakes.

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    Newswise — Washington, DC— As climate change warms the Earth, higher-latitude regions will be at greater risk for toxins produced by algal blooms, according to new research led by Carnegie’s Anna Michalak, Julian Merder, and Gang Zhao. Their findings, published in Nature Water, identify water temperatures of 20 to 25 degrees Celsius (68 to 77 degrees Fahrenheit) as being at the greatest risk for developing dangerous levels of a common algae-produced toxin called microcystin.  

    Harmful algal blooms result when bodies of water get overloaded with nitrogen and phosphorus runoff from agriculture and other human activities. These excess nutrients can allow blue-green algae populations to grow at an out-of-control rate.

    Some blue-green algal species produce a toxin called microcystin, which can pose a serious health hazard to people and the environment, as well as pose economic risks for fishing and tourism. Microcystin affects liver function and can cause death in wild and domestic animals, including humans in rare instances. It is also classified as a potential carcinogen in cases of chronic exposure.

    “In 2014 an algal bloom in Lake Erie led to high levels of microcystin in water intakes, and residents in Ohio and Ontario were instructed not to drink tap water due to risk of exposure,” Merder cautioned.

    Merder, Michalak, and their colleagues—Carnegie’s Gang Zhao, University of Kansas’s Ted Harris, and Dimitrios Stasinopoulos and Robert Rigby of the University of Greenwich—analyzed samples taken from 2,804 U.S. lakes between 2007 and 2017. They assessed how water temperature affects the occurrence and concentration of microcystin as part of an effort to better understand the risks to water quality posed by climate change.

    Michalak’s lab has taken a leading role in understanding the intersection of climate change and water quality impairments for more than a decade. Previous work has shown that lakes worldwide are already experiencing more severe algal blooms and that nutrient pollution is being exacerbated by changes in rainfall patterns.

    “Lakes are sentinels of climate change,” Michalak said. “They hold the vast majority, 87 percent, of the liquid freshwater on the Earth’s surface, and the warming and precipitation shifts associated with climate change pose some of the greatest threats to water quality around the world and to the health of aquatic ecosystems.”

    The surface temperatures of lakes have already been warming at 0.34 degrees Celsius (0.61 degrees Fahrenheit) per decade and Merder and Michalak set out to determine what this, as well as future warming, would mean in terms of risk for elevated toxin concentrations.

    “The abundance of blue-green algae is predicted to increase due to climate change as they outcompete other species,” Merder explained. “But previous field studies came to various conclusions about what this means for microcystin concentrations.”

    To inform land and water management strategies, it was important to quantitatively tie toxin levels to water temperature, which Merder and Michalak were able to accomplish through their extensive analysis of lake water samples, revealing that water temperatures in the 20 to 25 degrees Celsius (68 to 77 degrees Fahrenheit) range were most dangerous in terms of elevated microcystin concentrations. They also found that the impact of temperature is amplified when nutrient concentrations are high.

    By incorporating information from climate models, they were able to demonstrate that areas most susceptible to high toxin concentrations will continue to move northward. In some areas, the relative risk of exceeding water quality guidelines will increase by up to 50 percent in the coming decades. Additionally, they showed that toxin hazards will decrease in a small number of regions further south, as water temperatures begin to exceed those associated with the highest risk.

    “These findings should help demonstrate the serious risk to safe water for drinking, fishing, recreation, and other societal needs in many parts of the United States and the urgency for developing management strategies to prepare,” Michalak concluded. “When we think about water sustainability in the context of global change, we need to focus on the quality of the water as much as we focus on the amount of water.”

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    Carnegie Institution for Science

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  • Ancient sea monster discovery reveals oldest mega-predator

    Ancient sea monster discovery reveals oldest mega-predator

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    Newswise — The fossils were found 40 years ago in north-eastern France. An international team of palaeontologists from the Naturkunde-Museum Bielefeld in Germany, the Institute of Paleobiology of the Polish Academy of Sciences in Warsaw, Poland, the Natural History Museum in Luxembourg and The Museum of Evolution at Uppsala University in Sweden have now analysed them and identified them as a new pliosaur genus: Lorrainosaurus.

    Pliosaurs were a type of plesiosaur with short necks and massive skulls. They appeared over 200 million years ago, but remained minor components of marine ecosystems until suddenly developing into enormous apex predators. The new study shows that this adaptive shift followed feeding niche differentiation and the global decline of other predatory marine reptiles over 170 million years ago.

    Lorrainosaurus is the oldest large-bodied pliosaur represented by an associated skeleton. It had jaws over 1.3 m long with large conical teeth and a bulky ‘torpedo-shaped’ body propelled by four flipper-like limbs.

    “Lorrainosaurus was one of the first truly huge pliosaurs. It gave rise to a dynasty of marine reptile mega-predators that ruled the oceans for around 80 million years,” explains Sven Sachs, a researcher at the Naturkunde-Museum Bielefeld, who led the study.

    This giant reptile probably reached over 6 m from snout to tail, and lived during the early Middle Jurassic period. Intriguingly, very little is known about plesiosaurs from that time.

    “Our identification of Lorrainosaurus as one of the earliest mega-predatory pliosaurs demonstrates that these creatures emerged immediately after a landmark restructuring of marine predator ecosystems across the Early-to-Middle Jurassic boundary, some 175 to 171 million years ago. This event profoundly affected many marine reptile groups and brought mega-predatory pliosaurids to dominance over ‘fish-like’ ichthyosaurs, ancient marine crocodile relatives, and other large-bodied predatory plesiosaurs”, adds Daniel Madzia from the Institute of Paleobiology of the Polish Academy of Sciences, who co-led the study.

    Pliosaurs were some of the most successful marine predators of their time.

    “Famous examples, such as Pliosaurus and Kronosaurus – some of the world’s largest pliosaurs – were absolutely enormous with body-lengths exceeding 10 m. They were ecological equivalents of today’s Killer whales and would have eaten a range of prey including squid-like cephalopods, large fish and other marine reptiles. These have all been found as preserved gut contents”, said senior co-author Benjamin Kear, Curator of Vertebrate Palaeontology and Researcher in Palaeontology at The Museum of Evolution, Uppsala University.

    The recovered bones and teeth of Lorrainosaurus represent remnants of what was once a complete skeleton that decomposed and was dispersed across the ancient sea floor by currents and scavengers.

    “The remains were unearthed in 1983 from a road cutting near Metz in Lorraine, north-eastern France. Palaeontology enthusiasts from the Association minéralogique et paléontologique d’Hayange et des environs recognised the significance of their discovery and donated the fossils to the Natural History Museum in Luxembourg”, said co-author Ben Thuy, Curator at the Natural History Museum in Luxembourg.

    Other than a brief report published in 1994, the fossils of Lorrainosaurus remained obscure until this new study re-evaluated the finds. Lorrainosaurus indicates that the reign of gigantic mega-predatory pliosaurs must have commenced earlier than previously thought, and was locally responsive to major ecological changes affecting marine environments covering what is now western Europe during the early Middle Jurassic.

    “Lorrainosaurus is thus a critical addition to our knowledge of ancient marine reptiles from a time in the Age of Dinosaurs that has as yet been incompletely understood”, says Benjamin Kear.

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    Uppsala University

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  • Whaling decimated more fin whales than previously estimated

    Whaling decimated more fin whales than previously estimated

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    Key takeaways

    • Whaling in the 20th century destroyed 99% of the Eastern North Pacific fin whale breeding  population.
    • Because there is enough genetic diversity, current conservation measures should help the population rebound without becoming inbred.
    • The future of fin whales in the Gulf of California depends on the recovery of the Eastern North Pacific population.

    Newswise — A new genomic study by UCLA biologists shows that whaling in the 20th century destroyed 99% of the Eastern North Pacific fin whale breeding, or “effective,” population — 29% more than previously thought.

    But there is also some good news: Genes among members of this endangered species are still diverse enough that current conservation measures should be be enough to help the population rebound without becoming inbred. The study also found that the health of this group is essential for the survival of highly isolated, genetically distinct fin whales in the Gulf of California.

    The study, published in Nature Communications, is among the first to use whole genome information to get a picture of the size and genetic diversity of today’s population. Previous studies had to rely on whaling records or mitochondrial DNA, which is inherited only from the mother, providing limited genetic information.

    In the 19th century, whaling decimated most whale species around the world but left the largest ones — blue and fin whales — largely untouched. That changed with the advent of industrial whaling in the 20th century. By midcentury, close to a million fin whales worldwide had been slaughtered, at least 75,000 of these in the Eastern North Pacific.

    “When you look at whaling records, you can only tell how many were killed. You can’t tell how many there were to begin with,” said corresponding author Meixi Lin, who worked on the project as a UCLA doctoral student and is now a Carnegie Institution for Science postdoctoral fellow at Stanford University. “We know 20th century whaling was severe, but we didn’t know how severe it was for fin whales.”

    To find out, then-postdoctoral researcher and corresponding author Sergio Nigenda-Morales extracted DNA from tissue samples taken from wild fin whales in the Eastern North Pacific and the Gulf of California. He rounded this out with DNA provided by colleagues at the National Oceanic and Atmospheric Administration. In all, 50 whales were studied. Fin whales from the Gulf of California were included because the population there had been undisturbed by whaling, enabling researchers to assess their genetic diversity and learn how they were related to the Eastern North Pacific population.

    “Getting samples from live whales is hard, because you don’t know where they’re going to be —and when they come up, you only have a moment to take the sample before they go back underwater,” said Nigenda-Morales, now an assistant professor at Cal State San Marcos. “It is a humbling experience to conduct field research and interact with the second-largest animal on the planet.”

    The genome analyses revealed that the Gulf of California population diverged around 16,000 years ago, with a population that hovered around 114 adults of reproductive age. The population of breeding adults is a key indicator of a species’ ability to sustain itself. The Eastern North Pacific effective population remained at around 24,000 individuals for thousands of years, until a severe decline happened between 26 and 52 years ago — a period that coincides with 20th century whaling — to only about 305 individuals.

    Past ecological studies had suggested a 70% reduction in fin whale populations, while earlier genetic studies estimated a much larger pre-whaling population.

    “It’s usually hard to detect such strong recent reductions in the genome. But in this case, fin whales were really abundant before, which made the sudden reduction very obvious in our data. If the reduction hadn’t been so strong, we wouldn’t have been able to detect it,” Nigenda-Morales said.

    When a population suffers such a drastic decline, harmful genes left in the remaining organisms can become amplified over time as the small population size inevitably forces individuals carrying those genes to breed together. These harmful genes can reduce the health of the overall population and cause it to die out. Genetic diversity is still high among Eastern North Pacific whales, meaning that multiple versions of many genes are still plentiful and harmful genes have not yet become common.

    “Most of this variation originated long, long ago, so genetic diversity in the small number of surviving individuals comes from their ancient history,” said co-author Kirk Lohmueller, a UCLA professor of ecology and evolutionary biology.

    Luckily, thanks to the slow pace of fin whale reproduction, the population reduction caused by whaling at its strongest point lasted for only two fin whale generations — a 50-year span — and ended with the implementation of the international whaling moratorium in 1985. Since then, the population has slowly recovered, and harmful genes have not had time to pile up.

    However, computer simulations show that if the population remains at its current size, the diversity will begin to vanish. The study’s authors write that the most important thing governments can do to aid fin whale recovery is to continue to enforce the whaling ban so that fin whales have time to increase their numbers.

    The future of fin whales in the Gulf of California also depends on the recovery of the Eastern North Pacific population. The genomic analysis showed that many harmful genes have become common in the former group, and that the only source of new genetic variants is the occasional Eastern North Pacific whale who wanders into their territory about once in every three generations. This infusion of new genetic material, however, has been enough to keep the population going.

    For now, current protections for both populations appear sufficient, though they will need to remain in place for a long time. But climate change, ship strikes and other human-caused disturbances could jeopardize the species’ recovery. The authors expect that ongoing research will help identify additional conservation measures.

    “With improvement in computational models, we can incorporate factors like climate change and relate the risk of extinction from human-mediated processes with what’s happening at the genomic level,” said Lohmueller. “Continuing to develop such models is as important as collecting more data.”

    Nigenda-Morales and Lin undertook the research as doctoral students of UCLA professor and senior author Robert Wayne, who continued working on the project until he passed away late last year. The authors have dedicated the paper to him.

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    University of California Los Angeles (UCLA)

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  • Antarctic fur seals face new threat.

    Antarctic fur seals face new threat.

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    Newswise — Antarctic fur seals that were hunted to near extinction have recovered but now face dangerous decline because of a lack of food, new research suggests.

    The study of fur seals, almost all of which live on the sub-Antarctic islands of South Georgia, shows that the modern-day population peaked in 2009 at about 3.5 million – a healthy number, although significantly less than previously estimated. But a more detailed count of animals living on a particular South Georgia island called Bird Island also shows the seals are finding it harder to find krill – a small shrimp-like crustacean – with numbers crashing in the last decade.

    The research is carried out by scientists at the British Antarctic Survey (BAS) and colleagues and is published in the journal Global Change Biology.

    Jaume Forcada, a BAS scientist who led the new study and is lead author on the paper, says:

    “We found both good and bad news about the fur seals. The population has recovered very impressively throughout the twentieth century when seal hunting was banned. But twenty-first century changes to the abundance of krill in the Southern Ocean are now threatening these iconic animals all over again.” 

    Prized and hunted for their pelts in the 1700s and 1800s, by the early 1900s there were too few animals left to hunt commercially. Combined with stronger conservation protections, plenty of food and fast breeding, the population boomed and recovered much more quickly than other previously hunted species in the region, including humpback whales. By the year 2000, South Georgia was reportedly home to between 4.5 million and 6.2 million fur seals. However, re-examination of this data and the methods used suggests that these booming population numbers were not accurate – offering a further challenge to scientists now trying to understand the current decline.

    Forcada continues: “Our new results show this was a massive overestimation. That matters because the fur seal population size is used to judge the overall health of the species and the wider Antarctic ecosystems. And it turns out that neither were as robust as people thought.”

    Counting seals is harder than it may appear. Surveys typically assess numbers at seal breeding beaches, but these figures are skewed because most male fur seals at South Georgia don’t usually breed until they are ten-years old, and then only for two to three years. That means some 80% of the male population is missing from surveys, and how researchers account for this can overstate the overall count.  

    The new estimate of 3.5 million animals comes from several week-long helicopter surveys of South Georgia from 2007 to 2009 and improved population assessment methods.

    Fur seal populations at Bird Island, a well-studied location in the northwest of South Georgia, showed among the fastest rebounds over the last century or so. But the new survey identified a worrying reversal: numbers peaked in 2009 and have declined by 7% each year since. That takes the island’s current population down to a level not seen since the 1970s, when the population was still recovering.

    Scientists looked for evidence of krill fishing pressure on fur seal population dynamics, but this was not found to be significant. However, initial analysis of climate data shows that that rapidly rising sea temperatures in the region correlate with the seal population decline – pointing to a loss of krill as the most likely cause. 

    “Krill can make up to 80% or more of the diet of fur seals at South Georgia, so they experience catastrophic declines in the number of pups produced and survival of individuals when environmental conditions remove the krill from their immediate foraging areas,” Forcada says.

    This sensitivity of fur seals to krill availability, along with the existence of longer-term population data, is what makes them an important known indicator for the ecosystems around Bird Island. More detailed research is needed to establish why krill around Bird Island is now less available, and how widespread the change could be across the rest of the Southern Ocean.

    “If the pressure on the fur seals at Bird Island also applies to the greater South Georgia population there could be an ongoing decline there as well. So even though there were three and a half million of them there, the fast decline at Bird Island tells us they could be in trouble,” Forcada says.

    Ninety years of change, from commercial extinction to recovery, range expansion and decline for Antarctic fur seals at South Georgia, by Jaume Forcada, Joseph I. Hoffman, Olivier Gimenez, Iain J. Staniland, Pete Bucktrout, Andrew G. Wood is published in Global Change Biology on Monday 16 October.

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  • 70 Extinct Fish Thriving Again

    70 Extinct Fish Thriving Again

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    Newswise — The houting, a fish species that lived in North Sea estuaries and is officially extinct, turns out to be alive and well. Researchers from the University of Amsterdam and the Natural History Museum London extracted DNA from multiple houtings conserved in the museum, up to 250+ years old. Next they compared the DNA of these museum fish with DNA from various currently occurring sibling species. The biologists found hardly any genetic difference between houting and a species called European whitefish. Since this species is still common, houting also isn’t extinct.

    In a recent publication in the journal BMC Ecology and Evolution, the researchers describe how they isolated mitochondrial DNA from the fish. They even managed to obtain a small piece of DNA from a dried North Sea houting from 1754 that was used by Linnaeus for the official species description. Next they used the DNA to create a phylogenetic tree, in which all examined houting (Coregonus oxyrinchus) ended up in the same group as the European whitefish (Coregonus lavaretus).

    Not extinct

    According to the researchers, houting is therefore not a separate species. First author Rob Kroes of the University of Amsterdam comments: ‘The European whitefish is fairly widespread in Western and Northern Europe, both in freshwater rivers and lakes, estuaries and the sea. Because we found no species difference between houting of the past and today’s European whitefish, we do not consider the houting to be extinct.’

    External traits vs DNA

    So, how is it possible that the houting was officially declared extinct in 2008? Kroes: ‘It often happens that there is confusion as to whether animals are one species or not. Especially when fish are involved. They often have a lot of variation in morphological traits within a species. In this case, biologists long thought that houting is a different species from the European whitefish due to the length of the snout and the number of gill rakers. But these traits are simply not suitable to say that houting is a different species. Our DNA research now clearly shows that it isn’t.’

    Name change

    A change of the official Latin species name seems to be in order. However, a definitive adjustment of the name requires a bit of additional research on the DNA of the dried fish from 1754. According to the researchers, this will be difficult to do. Kroes: ‘The DNA is old and damaged, but I think we should try. At the moment, the protected status of various coregonids is a mess. According to the IUCN, North Sea houting is extinct; at the same time, there are various European nature laws that state that both houting and European whitefish must be protected. So we are actually protecting an extinct species that is just swimming around at the moment.’

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    Universiteit van Amsterdam

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  • Florida Keys’ new “margarita snails” are bright yellow

    Florida Keys’ new “margarita snails” are bright yellow

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    Newswise — The “Margaritaville” in Jimmy Buffett’s famous song isn’t a real place, but it’s long been associated with the Florida Keys. This string of tropical islands is home to the only living coral barrier reef in the continental US, along with many animals found nowhere else in the world. One of them is a newly-discovered, bright yellow snail, named in honor of Margaritaville. The lemon- (or, key-lime-) colored snail, along with its lime-green cousin from Belize, is the subject of a study published in the journal PeerJ.

    These marine snails are distant relatives of the land-dwelling gastropods you might find leaving slimy trails in your garden. Nicknamed “worm snails,” they spend most of their lives in one place. “I find them particularly cool because they are related to regular free-living snails, but when the juveniles find a suitable spot to live, they hunker down, cement their shell to the substrate, and never move again,” says Rüdiger Bieler, curator of invertebrates at the Field Museum in Chicago and the study’s lead author. “Their shell continues to grow as an irregular tube around the snail’s body, and the animal hunts by laying out a mucus web to trap plankton and bits of detritus.”

    Bieler has spent the past four decades studying invertebrate animals living in the Western Atlantic, but these particular snails “are so small and so well-hidden that we’ve not encountered them before during our scuba diving surveys. We had to look very closely,” he says. The new species belong to the same family of marine snails as the invasive “Spider-Man” snail that the same team described from the Vandenberg shipwreck off the Florida Keys in 2017.  

    He and his colleagues, including fellow Field Museum curator Petra Sierwald, came across the lemon-yellow snails in the Florida Keys National Marine Sanctuary, and they found a similar, lime-colored snail in Belize. “Many snails are polychromatic– within the same species, you get different colors,” says Bieler. “In a single population, even a single little cluster, one might be orange, one might be gray. I think they do it to confuse fish and not give them a clear target, and some have warning coloration.”

    “Initially, when I saw the lime-green one and the lemon-yellow one, I figured they were the same species,” says Bieler. “But when we sequenced their DNA, they were very different.”

    Based on these molecular data, Bieler, Sierwald, and their co-authors Timothy Collins, Rosemary Golding, Camila Granados-Cifuentes, John Healy and Timothy Rawlings, placed the snails in a new genus, Cayo, after the Spanish word for a small, low island. The yellow snail was named Cayo margarita after the citrusy drinks in Jimmy Buffet’s “Margaritaville.” The lime snail’s name, Cayo galbinus, means “greenish-yellow.” 

    The Cayo snails have a key trait in common with another worm snail genus, Thylacodes, for which the team described a new species from Bermuda and named Thylacodes bermudensis. While only distantly related, these snails all have brightly colored heads poking out of their tubular shells. “Our thought is this is a warning color,” says Bieler. “They have some nasty metabolites in their mucus. That also might help explain why they’re able to have exposed heads– on the reef, everybody is out to eat you, and if you don’t have any defensive mechanism, you will be overgrown by the corals and sea anemones and all the stuff around you. It seems like the mucus might help deter the neighbors from getting too close.”

    Bieler says that the study is important because it helps illuminate the biodiversity of coral reefs, which are under severe threat due to climate change. “There have been increases in global water temperatures, and some species can handle them much better than others,” says Bieler. The Cayo snails have a tendency to live on pieces of dead coral, and as more coral is killed off, the snails might spread. 

    Moreover, says Bieler, “it’s another indication that right under our noses, we have undescribed species. This is in snorkeling depth in a heavily touristed area, and we’re still finding new things  all around us.”

    This study was contributed to by scientists at the Field Museum, Florida International University, Queensland Museum, and Cape Breton University. 

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  • New study shows signs of early creation of modern human identities

    New study shows signs of early creation of modern human identities

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    BYLINE: Wits University

    Newswise — A new study confirms previous scant evidence and supports a multistep evolutionary scenario for the culturalization of the human body.

    The new study, which was conducted by Francesco d’Errico, Karen Loise van Niekerk, Lila Geis and Christopher Stuart Henshilwood, from Bergen University in Norway and the University of the Witwatersrand (Wits) in Johannesburg, South Africa, is newly published in the Journal of Human Evolution. Its significant findings provide vital information about how and when we may have started developing modern human identities.

    “The discovery of eye-catching unmodified shells with natural holes from 100 to 73 years ago confirms previous scant evidence that marine shells were collected, taken to the site and, in some cases, perhaps worn as personal ornaments. This was before a stage in which shells belonging to selected species were systematically, and intentionally perforated with suitable techniques to create composite beadworks,” says van Niekerk.

    The shells were all found in the Blombos Cave, on the southern Cape of South Africa’s coastline. Similar shells have been found in North Africa, other sites in South Africa and the Mediterranean Levant, which means that the argument is supported by evidence from other sites, not just Blombos Cave.

    Confirms scant evidence of early beadwork

    In other words, the unperforated and naturally perforated shells provide evidence that marine shells were collected and possibly used as personal ornaments before the development of more advanced techniques to modify the shells for use in beadworks at around 70 years ago.

    Van Niekerk says that they know for sure that these shells are not the remains of edible shellfish species that could have been collected and brought to the site for food.

    “We know this because they were already dead when collected, which we can see from the condition of most of the shells, as they are waterworn or have growths inside them, or have holes made by a natural predator or from abrasion from wave action.”

    The researchers measured the size of the shells and the holes made in them, as well as the wear on the edges of the holes that developed while the shells were worn on strings by humans. They also looked at where the shells came from in the site to see whether they could be included in different groups of beads found close together that could have belonged to single items of beadwork. These techniques provide insights into the potential use of these shells for symbolic purposes.

    Early signs of possibly creation of identity

    Van Niekerk says that they identified 18 new marine snail shells from 100 to 70 years ago, that could have been used for symbolic purposes, and proposed a multistep progression for the culturalisation of the human body with roots in the deep past.

    “With this study we specifically show that humans gradually complexified practices of modifying their appearance and transformed themselves into tools for communication and storage of information. We also think we can possibly see a creation of identity that gradually but radically changed the way we look at ourselves and others, and the nature of our societies,” says van Niekerk.

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    University of the Witwatersrand, Johannesburg

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  • MSU finds genetic rescue is underused for endangered species recovery

    MSU finds genetic rescue is underused for endangered species recovery

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    Newswise — EAST LANSING, Mich. – During a recent review of the U.S. Fish and Wildlife Service’s recovery plans for more than 200 endangered and threatened vertebrate species in the United States, Michigan State University researchers made an interesting discovery. They found that two-thirds of these species could benefit from a gene-boosting diversity strategy known as genetic rescue. Surprisingly, just three of these plans to support species recovery currently use this approach.

    Genetic rescue is an increase in population size caused by the movement of new genetic material from one population to another. This can happen through either human-assisted intervention or natural migration. As a conservation tool, this strategy can increase the genetic diversity of small, isolated populations and help them recover from inbreeding.

    “These small, isolated populations are becoming more frequent, fragmented and in trouble,” said Sarah Fitzpatrick, an associate professor in the Department of Integrative Biology in the College of Natural Science and a W.K. Kellogg Biological Station faculty member. “They might benefit from some human-assisted migration to help infuse deteriorating populations with more genetic variation, which can help them respond to changes in the environment as well.”

    Translocating, or the act of moving individuals from one place to another, is a common practice that has most often been used outside the context of genetic rescue. 

    “This is pretty common in fish management,” said Cinnamon Mittan-Moreau, an MSU Ecology, Evolution and Behavior Presidential Postdoctoral Fellow based at KBS. “Managers have been moving animals and plants around for more than a century, just not with the intention of increasing genetic variation.”

    The good news is that, in many cases, the logistics of carrying out these translocations have already been overcome, and so the time is ripe for more attempts at genetic rescue. Despite this, however, this strategy continues to be left out of species recovery plans.

    “We found that over two-thirds of the 222 species we evaluated would be good candidates for consideration of genetic rescue,” said Fitzpatrick. “And yet, we found only three examples of implementation of genetic rescue. As genomic resources become available for more species, we hope to see increased incorporation of genetic information in recovery planning, including informed translocation actions for the purpose of genetic rescue.”

    Along with Fitzpatrick and Mittan-Moreau, co-authors on this study include post-doctoral researcher Jessica Judson and former laboratory manager Madison Miller.

    “There’s a lot of opportunity for this to help, but we don’t see it very often,” said Mittan-Moreau. “No one had done this full review to see if this could be considered more often for endangered species plans.”

    The paper was published in the Journal of Heredity.

    Read on MSUToday.  

    ###

    Michigan State University has been advancing the common good with uncommon will for more than 165 years. One of the world’s leading research universities, MSU pushes the boundaries of discovery to make a better, safer, healthier world for all while providing life-changing opportunities to a diverse and inclusive academic community through more than 400 programs of study in 17 degree-granting colleges. 

    For MSU news on the Web, go to MSUToday. Follow MSU News on Twitter at twitter.com/MSUnews.

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    Michigan State University

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  • Richard W. Mies awarded Livermore’s 2023 John S. Foster Medal

    Richard W. Mies awarded Livermore’s 2023 John S. Foster Medal

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    Newswise — Lawrence Livermore National Laboratory Director Kim Budil today announced that the 2023 John S. Foster, Jr. Medal is awarded to retired U.S. Navy Admiral Richard W. Mies. The 8th recipient of the prestigious Foster Award, Mies has served as a member of the LLNL Board of Governors since 2004 and is being recognized for his exceptional and inspirational career dedicated to national security, nuclear deterrence, and scientific innovation. Mies will be recognized at ceremony in his honor in Livermore on Oct.18. 

    “Admiral Mies embodies the highest ideals of service to our nation,” Budil said. “His dedication to national security and innovation – and nuclear deterrence in particular – has had a profound impact. He continues to act as a bridge between the Department of Defense, National Nuclear Security Administration, and the nuclear security enterprise, fostering the highest sense of purpose and commitment to teamwork. We are honored to recognize his remarkable contributions with the 2023 John S. Foster Jr. Medal.” 

    A distinguished nuclear submarine officer, Mies served a 35-year career in the U.S. Navy and held various key positions, including leading U.S. Strategic Command for four years. Following his retirement in 2002, he continued to contribute significantly to national security, serving as a senior vice president of Science Applications International Corporation and as the chairman of the Department of Defense Threat Reduction Advisory Committee. He presently serves as chairman of the U.S. Strategic Command   Strategic Advisory Group and the Oak Ridge National Laboratory national security science directorate advisory board. He is also a long-standing member of the National Academy’s Committee on International Security and Arms Control.

    A distinguished graduate of the US Naval Academy, Mies completed post-graduate education at Oxford University, the Fletcher School of Law and Diplomacy, and Harvard University. He holds a master’s degree in government administration and international relations. 

    “Dr. Johnny Foster is an icon in our strategic deterrence community, and I am deeply honored and indeed humbled to have been selected for this prestigious award named after him,” Mies said. “I have been privileged to have worked closely with many of the past Foster Award recipients and am deeply indebted and grateful to each of them for their mentorship, friendship, and their sustained, distinctive, and selfless service to our Nation.” 

    The John S. Foster Jr. Medal, administered by Lawrence Livermore National Security, was established to honor individuals who embody the qualities that distinguished Dr. John S. Foster Jr. throughout his career, including strong national security focus, inspiring leadership, integrity, and scientific innovation. This award also recognizes cultivation inclusive teamwork and an atmosphere of openness in national security innovation, which Mies has consistently championed.

    Each year, the LLNL director bestows the Foster Medal upon a deserving recipient, who receives a citation, a gold medal bearing the likeness of John S. Foster Jr., and a $25,000 cash award. Past honorees include pioneers in nuclear security, military strategy, and arms control, each with impactful contributions to national security and scientific advancement.

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    Lawrence Livermore National Laboratory

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  • Paleoclimate Lab Researchers Use National Science Foundation Support to Study Climate Change Past

    Paleoclimate Lab Researchers Use National Science Foundation Support to Study Climate Change Past

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    Newswise — ALBANY, N.Y. (Aug. 31, 2023) — Last summer, the University at Albany’s Paleoclimate Lab opened its doors, offering a new way to analyze samples of natural materials, such as coral and lake sediment, to help reconstruct Earth’s climate history.

    Now, through nearly $800,000 in new support from the National Science Foundation (NSF) this summer, lab researchers are focused on South Asia and the Middle East.

    Aubrey Hillman, an assistant professor in UAlbany’s Department of Atmospheric and Environmental Sciences (DAES), was awarded $417,242 from the NSF for a collaborative research project to create a 50,000-year continuous record of the Indian summer monsoon by analyzing lake sediment collected from Loktak Lake in Northeast India.

    Sujata Murty, a DAES assistant professor, was awarded $339,771 from the NSF to lead another collaborative research project that aims to reconstruct Red Sea surface hydrology since the 1700s by analyzing coral cores along its eastern edge.

    Both projects are now active and will run through the summer of 2026.

    “The NSF Paleoclimate program is highly competitive; therefore, it is notable that both of these projects were funded,” said Ryan Torn, DAES chair and professor. “Aubrey and Sujata’s work will provide greater insight into Earth’s past climate and offer new research opportunities for both undergraduate and graduate students.”

    Changes in the Indian Summer Monsoon

    The Indian summer monsoon typically lasts from June to September, with much of India, along with other parts of South Asia, receiving a significant amount of its total annual precipitation during this period.

    Hillman’s new NSF project proposes to create new paleoclimate records from Loktak Lake that will provide insight into the causes and consequences of abrupt changes in Indian summer monsoon rainfall over the last 500 centuries.

    To do so, Hillman and her research team, which includes collaborators at the University of Pittsburgh, Manipur University in India and Washington University in St. Louis are using the Paleoclimate lab to analyze lake sediments collected through the project.

    In 2018, the research team traveled to Loktak Lake to start the collection process, using a UWITEC coring device that lowers a long tube to the bottom of the lake and fills it with sediment cores. That tube is then brought home, preserved and analyzed.

    The team plans to return within the next year, collecting a total of 30 meters of lake sediment.

    “The lake sediments will offer us new data to analyze changes in the Indian summer monsoon season over tens of thousands of years,” said Hillman. “There are few records that currently exist at this long of a scale.

    “We believe our findings will offer new insight into the timing, direction, magnitude, and rate of changes in the Indian monsoon season through history, all of which are important to the more than one billion people who rely on it to deliver water and support agriculture,” she added.

    Following the sample collections, the research team plans to hold a series of public engagement workshops with colleagues in India regarding topics such as lake water balance, paleoclimate and monsoons. The project is also supporting graduate student researchers from partnering institutions.

    Climate of the Red Sea

    Our oceans play a critical role in influencing regional and global climate by absorbing much of the solar energy that reaches Earth and releasing heat back into the atmosphere.

    While there’s significant research around the climate history of the Atlantic and Pacific Oceans, the Indian Ocean, the third largest of the world’s five modern oceans, is much less understood.

    Murty’s NSF research project, which includes collaborators from the Woods Hole Oceanographic Institution and Union College, will focus on analyzing coral samples to determine how climate variability over the last 300 years has impacted ocean circulation in the Red Sea, a marginal sea of the Indian Ocean.

    “The Indian Ocean is one of the most under-observed tropical ocean regions in the world,” Murty said. “We do not have a strong understanding of past Indian Ocean climate or ocean circulation patterns, so I’ve been slowly moving my research over to this area, beginning with the marginal seas, such as the Red Sea.”

    “Our research findings will lead to improved understanding of Red Sea hydrographic variability and interactions with regional climate, aiding in climate and ocean circulation prediction efforts in the region,” she added.

    Corals have annual growth layers, similar to tree rings, that can offer valuable information on how environmental conditions have changed over time and provide insight for future climate modeling.

    Oceanographers like Murty scuba dive in the ocean and drill cores from massive boulder corals, taking care not to harm them. The samples for the new research were collected prior to this project and are now in the Paleoclimate Lab. 

    Along with analyzing the corals, project researchers also plan to participate in art-science outreach initiatives such as Synergy II, a collaborative project between Art League RI and the Woods Hole Oceanographic Institution that offers a unique opportunity to share ocean science research through artistic expression.

    The NSF funding also supports graduate and undergraduate students assisting with the coral analysis.

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    University at Albany, State University of New York

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  • Scientists Studying Idalia in Real-Time Available to Comment on Hurricanes and Warming Oceans

    Scientists Studying Idalia in Real-Time Available to Comment on Hurricanes and Warming Oceans

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    Newswise — Is there a connection between the incidence of hurricanes and warming oceans? What do we know?

    Travis Miles and Scott Glenn, physical oceanographers at the Rutgers School of Environmental and Biological Sciences, have answers.

    The following quotes from Miles and Glenn are available to the media covering the issue.

    Quote from Miles:

    “Hurricanes draw their fuel from the oceans, intensifying over warm upper ocean features and weakening over cold ones. As our oceans warm ,we expect there to be more frequent major hurricanes with strong winds, as well as increases in precipitation. The impacts of these storms will be further enhanced with increased sea level rise. To better understand and predict the impacts of these storms, we work with a consortia of partners to collect data ahead of and beneath these powerful storms with fleets of ocean robots.”

    Quote from Glenn:

    “Motivated by our shared experience in Hurricanes Irene and Sandy, we continue to build broad partnerships to better characterize the upper ocean heat content well ahead of landfalling hurricanes, and to better understand the rapid co-evolution of the ocean and atmosphere during intense hurricane forcing. Better observations and understanding of these extreme hurricane events leads to better forecasts, and that saves lives.”

     More information:

    • Miles and Glenn are partnering with other institutions to “fly” autonomous underwater robots known as gliders under hurricanes including Hurricane Idalia. This is part of active research in the Atlantic, Gulf of Mexico, and the Caribbean to observe what happens to oceans ahead of and during hurricanes.
    • Their research is providing data to the National Weather Service to enable better hurricane forecasting models.

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    Rutgers University-New Brunswick

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