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Something peculiar is happening in the azure waters off the rocky cliffs of Ischia, Italy. There, streams of gas-filled volcanic bubbles rising up to the surface are radically changing life around them by making seawater acidic. Stanford researchers studying species living near these gassy vents have learned what it takes to survive in acidic waters, providing a glimpse of what future oceans might look like as they grow more acidic.

Volcanic carbon dioxide seeps from the ocean floor near Ischia, Italy [Credit: Pasquale Vassallo, Stazione Zoologica Anton Dohrn]

Their findings, published in Nature Communications, suggest that ocean acidification driven by human-caused carbon dioxide emissions could have a larger impact than previously thought.

"When an organism's environment becomes more acidic, it can dramatically impact not only that species, but the overall ecosystem's resilience, function and stability," said Stanford marine biologist Fiorenza Micheli, lead author on the paper. "These transformations ultimately impact people, especially our food chains."

A natural laboratory

Most ocean acidification studies to date have taken place in laboratories, making it impossible to assess how whole ecosystems comprised of multiple, interacting species would be affected. The real-life laboratory provided researchers an opportunity to examine dozens of species, from sea urchins to marine snails, that live in areas of different acidity along Ischia's volcanic carbon dioxide vents. In addition to studying how species diversity changed with acidification, they analyzed species traits, such as diet and growth, that influence how well the ecosystem performs. For example, sea snails were smaller in more acidic water, as their shells take longer to grow and are thinner and more brittle. These harmful effects on sea snails, a key food for animals higher up in the food chain, may affect fish populations.

Overall, the researchers found that the active venting zones with the most acidic waters were home to not only the least number of species, but also the lowest amounts of "functional diversity" – the range of ecosystem-support services or roles that each species can provide.

"Studying the natural carbon dioxide vents in Ischia allowed us to unravel which traits from different species, like snail shell strength, were more vulnerable to ocean acidification. These results illuminate how oceans will function under different acidification scenarios in the future," said lead author Nuria Teixidó, a marine biologist from Stazione Zoologica Anton Dohrn in Italy, who was a visiting researcher at Stanford during the research.

Acidification in the waters of Ischia displaced long-lived species, such as corals, that form habitat for other species – a process already often witnessed on reefs across the world. The researchers also found that high levels of carbon dioxide and more acidity favored species with short life spans and fast turnover as they are the only species that can resist these environmental conditions. This change could lead to further diversity loss and instability in the oceans, as biodiversity tends to increase an ecosystem's stability.

Biodiversity loss is mapped along a natural CO2 gradient [Credit: Nuria Teixidó, Stazione Zoologica Anton Dohrn]

A broader application

Localized case studies such as Ischia can shed light on how future global environmental conditions may affect ocean life. Beyond losing biodiversity, ocean acidification will threaten food security for millions of people who depend on seafood, along with tourism and other ocean-related economies.

"The effects of ocean acidification on whole ecosystems and their functioning are still poorly understood," said Micheli, a professor of biology. "In Ischia, we have gained new insights into what future oceans will look like and what key services, like food production and coastal production, will be lost when there is more carbon dioxide in the water."

Author: Nicole Kravec | Source: Stanford University [December 11, 2018]

NOAA's annual report card on the Arctic, released today at the American Geophysical Union fall meeting in Washington, D.C., measures the changing climate of the polar region including warmer air and ocean temperatures and declines in sea-ice that are driving shifts in animal habitats.

Eyeing the Arctic: The southern Greenland town of Narsaq. Photo taken during a NASA Operation IceBridge flight April 26, 2018 [Credit: NASA/Joe MacGregor]

Now in its 13th year, the 2018 Arctic Report Card is a peer-reviewed report that provides an annual status update on the region and compares these observations to the long-term record. It was compiled from the research of 81 scientists working for governments and academia in 12 nations. This information can be used to inform decisions by local, state and federal leaders as Arctic residents confront the challenges and opportunities posed by a rapidly changing climate and ecosystem.

"The environmental changes in the Arctic underscore why NOAA continues to invest in Arctic research and activities, which improve the nation's economic competitiveness, national security, and the sustainable management of natural resources," said retired Navy Rear Adm. Timothy Gallaudet, Ph.D., acting under secretary of commerce for oceans and atmosphere at NOAA, who led the news conference to release the report card. "This report will also help guide NOAA's priorities in better understanding the role of the Arctic in climate change and extreme weather; sustaining and growing fisheries; and supporting adaptation and economic opportunities in the region."


This year's report shows that the Arctic region experienced the second-warmest air temperatures ever recorded; the second-lowest overall sea-ice coverage; lowest recorded winter ice in the Bering Sea; and earlier plankton blooms due to early melting of sea ice in the Bering Sea.

In addition to annual updates on ocean temperature, snow cover, tundra greenness and melting on the Greenland Ice Sheet, the report card also includes reports on multi-year environmental changes, including a long-term population decline of the region's iconic wildlife species, the caribou. Other multi-year essays focused on the expansion northward of toxic harmful algae and significant concentrations of microplastic pollution that are transported by ocean currents into the Arctic Ocean from other parts of the global ocean.

Declining Arctic sea ice: The 2018 Arctic Report Card found the Arctic region had the second-lowest overall sea-ice coverage on record. The map shows the age of sea ice in the Arctic ice pack in March 1985 (left) and March 2018 (right) . Ice that is less than a year old is darkest blue. Ice that has survived at least 4 full years is white [Credit: Maps were provided by NOAA Climate.gov and based on data provided by Mark Tschudi./University of Colorado/ CCAR (NOAA Climate.gov)]

This report card is just one of many aspects of NOAA's role in the Arctic region. NOAA, alongside many partners, is monitoring Arctic conditions, pioneering innovative technologies, and creatively collecting data and other scientific information.

For example, new technology is revolutionizing our understanding of the Arctic's changing environment, beginning to fill critical gaps in ocean and atmospheric observations. This technology is unmanned, fast, cost-effective, sturdy enough to withstand icy temperatures, and able to collect quality data for lengthy periods. Further, NOAA Polar-orbiting satellites fly over the Arctic 28 times daily, collecting data vital to improve weather forecasts, help fisheries increase catch, and support safe, efficient navigation in challenging waters. Additionally, as Arctic waters become increasingly ice-free, and commerce and other interests grow, NOAA is working to update nautical charts and calculate tide and current predictions.

Source: National Oceanic and Atmospheric Administration (NOAA) [December 11, 2018]

Small, local patches of habitat could be playing a much bigger role in conserving biodiversity than you think, according to new research.

Eastern rosella at Edithvale wetland [Credit Wayne Butterworth]

The global study just published in the Proceedings of the National Academy of Sciences looked at the conservation values of vegetation patches in 27 countries on four continents, and considered their size and distance to other habitat.

The results were surprising according to lead researcher Professor Brendan Wintle from Melbourne University.

"Compared to large and well connected habitat areas, small and isolated patches of habitat have generally been treated as not very important to conservation," said Professor Wintle. "What we have found, however, is that small and isolated habitat areas are very important to the survival of many rare and endangered species."

"The environment is suffering a death by a thousand cuts," Wintle continued. "We need to re-think vegetation management regulations and policies that allow small patches of vegetation to be destroyed."

Co-author Dr. Sam Veloz, Climate Adaptation Group Director at Point Blue Conservation Science, added "We have many existing processes in place to fund restoration or conservation activities that are largely focused on large patches of habitat. While it's important to continue these efforts, our paper emphasizes that small but important habitat patches should be included in an overall conservation portfolio."

An example from the paper explored suitable habitat for four songbird species in California and Oregon (the streaked horned lark, savannah sparrow, Western meadowlark and the Oregon vesper sparrow). Research showed that highly fragmented parts of the study areas for each species contain habitat patches of very high conservation value. And the four species studied have ranges primarily in those small, isolated patches.

Dr. Heini Kujala from the University of Melbourne, another co-author, said that once you start considering how much habitat is left for a species, small patches can be very valuable.

"Small habitat patches can sometimes be the last pieces of a once widespread habitat. For species that rely on this type of habitat that makes them very important," said Dr. Kujala.

"Definitely we are not saying that it is an improvement to cut up big habitat areas into smaller pieces, rather that many of the small pieces that we have left are really important for conservation."

The study's authors hope that the research will raise awareness among planners, land managers, scientists, and the community about the value of small vegetation patches.

Source: University of Melbourne [December 11, 2018]

The new study, which detected bacteria from humans in the genus Salmonella and Campylobacter in Antarctic and Subantarctic marine birds, reveals the fragility of polar ecosystems and warns about the risk of massive deaths and extinctions of local fauna populations due pathogens.

These zoonotic agents, which cause common infections in humans, are caught by scavenger marine birds in contact with humans or livestock, and spread around the southern ocean [Credit: Jacob González-Solís/University of Barcelona-IRBio]

Reverse zoonosis: when the human species infects other living beings

Explorers, whalers, scientists -and lately, tourists-, are examples of human collectives that moved to the furthest regions of the planet. Some studies have claimed for years that there had been cases of reverse zoonosis, that is, infections humans give to other living beings. Despite some previous signs, scientific studies on zoonotic agents in the Antarctic and Subantarctic areas have been fragmented. Therefore, evidence is spread and not completely convincing in this field.

The new study, published in the journal Science of the Total Environment, studies the potential transmission of bacteria from humans to marine bird populations in four areas of the Antarctic and Subantarctic ecosystems. "Chronology and potential pathways for reverse zoonosis in these ecosystems are complex and difficult to study, but it seems they can be clearly related to the proximity of the fauna to inhabited areas and the presence of research stations", says Professor Jacob González-Solís, from the Department of Evolutionary Biology, Ecology and Environmental Sciences of the UB and IRBio.

Antibiotic-resistant bacteria in polar ecosystems

The study confirms the first evidence of reverse zoonosis related to the presence of human-origin bacteria Salmonella and Campylobacter in polar fauna. One of the warning signs was, in particular, the identification of Campylobacter strains, which are resistant to ciprofloxacin and enrofloxacin (common antibiotics in medicine and veterinary).

"Finding common Campylobacter genotypes in human species or livestock was the definite hint to prove that humans can be introducing pathogens in these regions", says Marta Cerdà-Cuéllar, researcher at the IRTA-CReSA. "These Salmonella and Campylobacter strains, which are a common cause for infections in humans and livestock, do not usually cause death outbreaks in wild animals. However, the emerging or invasive pathogens that arrive to highly sensitive populations -such as the Antarctic and Subantarctic fauna- could have severe consequences and cause the local collapse and extinction of some populations".

Northen and Southern Hemisphere: migrating route for marine birds and pathogens

The study shows the risk of reverse zoonosis is higher in areas that are closer to inhabited areas, such as the Flakland Islands, and probably the Tristan da Cunha archipelago. In this situation, the biological connectivity between Antarctic and Subantarctic communities through marine birds is a factor that would speed up the circulation of zoonotic agents among the ecosystems from different latitudes.

"This could be the case, for instance, of the Subantarctic parasite Stercorarius antarcticus: a scavenger marine bird could get the pathogen and spread it from Subantarctic latitudes to the Antarctica", says González-Solís.

Polar areas: not all the biodiversity is protected

The Antarctic Treaty protocol on Environmental Protection sets a series of principles that can be applied to human activity in Antarctica to reduce the human footprint in the white continent. However, some Subantarctic areas -which are also the habitat of birds such as the brown skua or the giant petrel- are not protected by the protecting regulation and could become the entrance for pathogen agents in polar ecosystems.

"Our results show it is easier for humans to introduce pathogen agents in the pristine areas in the Antarctica. As a result, pathogens entering the furthest ecosystems in the Southern Hemisphere could be a serious threat for the future of wildlife. Therefore, it is essential to adopt biosecurity measures to limit the human impacts in the Antarctica", notes Jacob González-Solís.

Source: University of Barcelona [December 10, 2018]

Dolphins in the northern Adriatic contain high levels of PCBs – highly toxic chemicals banned in the 1970s and 1980s – and are passing the pollutant to their young, according to new research led by a marine scientist at the University of St Andrews.

Credit: Tilen Genov/ University of St Andrews

An international team of researchers evaluated PCB and other organochlorine contaminants in bottlenose dolphins (Tursiops truncatus) living in the Gulf of Trieste (northern Adriatic Sea), the northernmost part of the Mediterranean Sea and one of the most human-impacted areas in the Mediterranean.

They found that, overall, 87.5% of dolphins had PCB concentrations above the toxicity threshold for the onset of physiological effects in marine mammals, while 65.6% had concentrations above the highest threshold published for marine mammals based on reproductive impairment in seals. Such high contaminant levels are of concern, particularly in combination with other threats to dolphins, including bycatch in fisheries, disturbance by boat traffic, and prey depletion.

The research, published in the journal Science of the Total Environment, involved Morigenos – Slovenian Marine Mammal Society (Slovenia), the Sea Mammal Research Unit at the University of St Andrews (UK), the Zoological Society of London's Institute of Zoology (UK), the Centre for Environment, Fisheries and Aquaculture Science (CEFAS, UK) and the Institute of Marine Sciences of the Italian National Research Council (Italy).

Credit: Genov et al, Morigenos – Slovenian Marine Mammal Society (Slovenia)

Tilen Genov, lead author of the study and a Ph.D. student at the University of St Andrews, said:

"We have been studying these dolphins for over 16 years, so we know most of them well. Through long-term re-sighting histories of identified individuals, we were able to link PCB levels in individual dolphins to parameters such as sex, reproductive output and social group membership.

"The research showed that males have significantly higher pollutant concentrations than females. This is because females offload a substantial amount of their toxicological burden to their young through gestation and lactation.

Credit: Tilen Genov/ University of St Andrews

"That is also why females that have not yet had calves had significantly higher concentrations than those that had previously produced at least one calf. Such results are expected based on our knowledge of mammal physiology, but it is not very common to demonstrate this phenomenon in wild whales and dolphins."

Dr. Paul Jepson, co-author of the study and specialist wildlife veterinarian at the Zoological Society of London's Institute of Zoology, said:

"This is another study showing high or very high levels of a very toxic and persistent pollutant – PCBs – in European dolphins. PCBs have the ability to cause diseases like cancer and can also suppress reproduction."

Source: University of St Andrews [December 10, 2018]

Parrots are famously talkative, and a blue-fronted Amazon parrot named Moises - or at least its genome - is telling scientists volumes about the longevity and highly developed cognitive abilities that give parrots so much in common with humans. Perhaps someday, it will also provide clues about how parrots learn to vocalize so well.

This photograph shows an Amazona aestiva taking care of the nest in Pantanal [Credit: Glaucia Seixas]

Morgan Wirthlin, a BrainHub post-doctoral fellow in Carnegie Mellon University's Computational Biology Department and first author of a report to appear in the journal Current Biology, said she and her colleagues sequenced the genome of the blue-fronted Amazon and used it to perform the first comparative study of parrot genomes.

By comparing the blue-fronted Amazon with 30 other long- and short-lived birds -- including four additional parrot species -- she and colleagues at Oregon Health and Science University (OHSU), the Federal University of Rio de Janeiro and other entities identified a suite of genes previously not known to play a role in longevity that deserve further study. They also identified genes associated with longevity in fruit flies and worms.

"In many cases, this is the first time we've connected those genes to longevity in vertebrates," she said.

This photograph shows Amazona aestiva chicks in Pantanal [Credit: Glaucia Seixas]

Wirthlin, who began the study while a Ph.D. student in behavioral neuroscience at OHSU, said parrots are known to live up to 90 years in captivity -- a lifespan that would be equivalent to hundreds of years for humans. The genes associated with longevity include telomerase, responsible for DNA repair of telomeres (the ends of chromosomes), which are known to shorten with age. Changes in these DNA repair genes can potentially turn cells malignant. The researchers have found evidence that changes in the DNA repair genes of long-lived birds appear to be balanced with changes in genes that control cell proliferation and cancer.

The researchers also discovered changes in gene-regulating regions of the genome -- which seem to be parrot-specific -- that were situated near genes associated with neural development. Those same genes are also linked with cognitive abilities in humans, suggesting that both humans and parrots evolved similar methods for developing higher cognitive abilities.

This photograph shows an Amazona aestiva taking care of the nest in Pantanal [Credit: Glaucia Seixas]

"Unfortunately, we didn't find as many speech-related changes as I had hoped," said Wirthlin, whose research is focused on the evolution of vocal behaviors, including speech. Animals that learn songs or speech are relatively rare -- parrots, hummingbirds, songbirds, whales, dolphins, seals and bats -- which makes them particularly interesting to scientists, such as Wirthlin, who hope to gain a better understanding of how humans evolved this capacity.

"If you're just analyzing genes, you hit the end of the road pretty quickly," she said. That's because learned speech behaviors are thought be more of a function of gene regulation than of changes in genes themselves. Doing comparative studies of these "non-coding" regulatory regions, she added, is difficult, but she and Andreas Pfenning, assistant professor of computational biology, are working on the computational and experimental techniques that may someday reveal more of their secrets.

Author: Byron Spice | Source: Carnegie Mellon University [December 06, 2018]

With rapid efficiency, a mysterious parasite is seeking out and killing a giant species of clam found only in the Mediterranean Sea. Unless scientists can find a way of stopping it soon, they say the mollusk could go extinct.

A diver observes a pen shell on the seabed in the Aegean Sea [Credit: Yiannis Issaris/AP]

For thousands of years, the emblematic noble pen shell has been intrinsically connected to human civilization. The largest bivalve in the Mediterranean can grow to more than a meter (three feet) long and has provided food and one of the world’s rarest materials: sea silk spun from fibers it uses to secure itself to the seabed. The mollusk also contributes to clear water by filtering out organic particulates.

The pen shell, Pinna nobilis, has been on the European Union’s protected species list for decades because of overfishing, pollution and the destruction of its natural habitat, meaning any fishing is banned. But the ban is often poorly enforced, with the animal harvested for food or for its shell, which is used for decorative purposes.

A pen shell stands on the seabed of the Aegean Sea [Credit: Yiannis Issaris/AP]

The pen shells, which have a life span of several decades and take years to reach reproductive age, were already dying faster than they could be replaced. So the spread of the microscopic parasite, which first appeared in the western Mediterranean in late 2016 and was identified just this year as a new species, has alarmed experts.

Exactly how the parasite kills isn’t completely clear, although scientists have found it attacks the pen shell’s digestive system. The infected animal is also unable to close its shell, incapacitating its defense against predators. Once infected, death is almost certain.

Yiannis Issaris, marine ecologist and research associate at the Hellenic Center for Marine Research, holds a dead noble pen shell, or Pinna nobilis, in Anavyssos, south of Athens [Credit: Thanassis Stavrakis/AP]

“In less than a year it wiped out (the pen shell population of) the Spanish coast,” said Maria del Mar Otero of the International Union for Conservation of Nature.

Soon parts of France, Malta, Tunisia and Italy were affected. In recent weeks, tests confirmed the same parasite, Haplosporidium pinnae, is responsible for pen shell die-offs in parts of Greece, and researchers have reported mass mortality as far east as Turkey and Cyprus.

Pen shells stand on the seabed in the Aegean Sea [Credit: Yiannis Issaris/AP]

Scientists are now racing to understand how the parasite spreads and its life cycle — essential information for a successful rescue program. One theory is that it could be spreading through phytoplankton, the bivalve’s food source, but nobody knows for certain.

“We cannot be sure of anything at this point,” said Pantelis Katharios, senior researcher at the Institute of Marine Biology, Biotechnology and Aquaculture of the Hellenic Center for Marine Research, or HCMR.

A dead pen shell stands open in a seagrass meadow in the Aegean Sea's Saronic Gulf [Credit: Elena Becatoros]

“What we know now is that the Pinnas are dying, that the cause is this parasite, and we know that it’s spreading very, very rapidly,” he said. “And that is going to be a huge problem (for) the ecology and the balance of the ecosystem in the Mediterranean.”

Yiannis Issaris, marine ecologist at the HCMR’s Institute of Oceanography, initially noticed widespread pen shell death off the coast of Anavyssos, southeast of Athens, in mid-summer. He suspected the culprit could be the same one causing mortality in Spain — and testing proved him right.

A pen shell stands anchored in the seabed of the Aegean Sea [Credit: Yiannis Issaris/AP]

Now the question is how to tackle the outbreak.

“This is very fresh for the scientific community,” Issaris said. “We’re still at the stage of recording where it has spread to.”

Yiannis Issaris, marine ecologist and research associate at the Hellenic Center for Marine Research, takes measurements of a dead noble pen shell, or Pinna nobilis, in Anavyssos, south of Athens [Credit: Thanassis Stavrakis/AP]

Some parts of Greece still have healthy populations of the mollusks, he noted, whereas in other areas they have been wiped out.

Protecting the pen shell in its natural habitat — sandy seabeds or seagrass meadows — appears “difficult to impossible,” Issaris said, particularly without knowing how the parasite spreads. In Spain, some healthy individuals were moved to aquariums.

Yiannis Issaris, marine ecologist and research associate at the Hellenic Center for Marine Research, takes measurements of a dead noble pen shell, or Pinna nobilis, in Anavyssos, south of Athens [Credit: Thanassis Stavrakis/AP]

Although tests are pending in some Mediterranean countries witnessing mass die-offs, experts have little doubt what the results will show.

“It’s very, very, very likely” to be the same parasite, Otero said. “There’s almost no question.”

Christina Pavloudi, foreground, post-doctoral researcher at the Hellenic Center for Marine Research laboratory on the Greek island of Crete, and Georgia Sarafidou, a student at the same facility, carry out tests on samples of noble pen shells stricken by a new parasite [Credit: Thanassis Stavrakis/AP]

One thing’s clear: the parasite is very particular in its choice of victim. A smaller, related species, the Pinna rudis, which also exists outside the Mediterranean, is unaffected.

“We don’t know how it has appeared in the Mediterranean... We only know that it causes mortality only in the Pinna nobilis,” Issaris said.

Yiannis Issaris, marine ecologist and research associate at the Hellenic Center for Marine Research, holds a dead noble pen shell, or Pinna nobilis, in Anavyssos, south of Athens [Credit: Thanassis Stavrakis/AP]

In the clear, shallow waters south of the Greek capital, dozens of dead pen shells lie scattered in a seagrass meadow, testament to the devastation.

Peering through a microscope at the tissue of an infected individual in his office in Crete, Katharios points out the culprit: small, oval-shaped parasites spread throughout the sample.

Scientists are puzzling over why an organism would be so lethal to the very species it depends on for its own survival.

Pantelis Katharios, senior researcher at the Institute of Marine Biology, Biotechnology and Aquaculture of the Hellenic Center for Marine Research on the Greek island of Crete, checks microscope imaging of a new parasite killing  the noble pen shell, or Pinna nobilis [Credit: Elena Becatoros]

“Normally parasites in nature do not have any benefit from harming the host, because they depend on the host,” Katharios explained. “But once in a while we may come across incidents like this, where we have massive mortalities.”

This could just be a natural phenomenon in which the parasite will eventually be wiped out along with its host, he said. Another possibility is that it originated in a different species and for some reason jumped to the pen shell. A third is that the pen shell’s immune system has been compromised by factors such as pollution, climate change or water temperature fluctuations.

“It’s extremely, extremely difficult to find the truth at this stage,” Katharios said.

Author: Elena Becatoros | Source: Associated Press [December 04, 2018]

Tests on more than 100 sea turtles—spanning three oceans and all seven species—have revealed microplastics in the guts of every single turtle.

Credit: Belle Co, Pexels.com

Researchers from the University of Exeter and Plymouth Marine Laboratory, working with the Greenpeace Research Laboratories, looked for synthetic particles (less than 5mm in length) including microplastics in 102 sea turtles in the Atlantic, Pacific and Mediterranean.

Synthetic particles were found in all of the turtles, the most common being fibres, which can potentially come from sources including clothing, tyres, cigarette filters and maritime equipment such as ropes and fishing nets.

"The effect of these particles on turtles is unknown," said lead author Dr. Emily Duncan, of the Centre for Ecology and Conservation on the University of Exeter's Penryn Campus in Cornwall.

"Their small size means they can pass through the gut without causing a blockage, as is frequently reported with larger plastic fragments. However, future work should focus on whether microplastics may be affecting aquatic organisms more subtly. For example, they may possibly carry contaminants, bacteria or viruses, or they may affect the turtle at a cellular or subcellular level. This requires further investigation."

In total, more than 800 synthetic particles were found in the 102 turtles studied. But researchers only tested part of each animal's gut—so the total number of particles is estimated to be about 20 times higher.

Researchers do not currently understand how synthetic particles are ingested by turtles, but the likely sources are polluted seawater and sediments, and eating via prey or plants.

Professor Brendan Godley, senior author of the study, added: "It really is a great shame that many or even all of the world's sea turtles have now ingested microplastics. At the moment, this is not the main threat to this species group but it is a clear sign that we need to act to better govern global waste."

Necropsies were carried out on the turtles after they died either by stranding or bycatch (accidental catching in fishing). The study sites were North Carolina, USA (Atlantic), Northern Cyprus (Mediterranean) and Queensland, Australia (Pacific).

The turtles with the most synthetic particles were in the Mediterranean—thought to have higher rates of contamination than the Atlantic or Pacific—but this study's sample sizes and methodology did not allow for detailed geographical comparisons.

Dr. Penelope Lindeque, of Plymouth Marine Laboratory, said: "While this study has been successful, it does not feel like a success to have found microplastic in the gut of every single turtle we have investigated.

"From our work over the years we have found microplastic in nearly all the species of marine animals we have looked at; from tiny zooplankton at the base of the marine food web to fish larvae, dolphins and now turtles. This study provides more evidence that we all need to help reduce the amount of plastic waste released to our seas and maintain clean, healthy and productive oceans for future generations."

Louise Edge, plastics campaigner at Greenpeace, said: "This important research demonstrates the breadth of our plastics pollution problem. Our society's addiction to throwaway plastic is fuelling a global environmental crisis that must be tackled at source."

The paper is published in the journal Global Change Biology.

Source: University of Exeter [December 04, 2018]

Sharks that use a whip-like tail to stun their prey, rays with saws on their faces, and river rays half the length of a bus are among the most unique species at risk of extinction according to the latest ranking from international conservation charity ZSL's (Zoological Society of London) pioneering EDGE of Existence programme.

The largetooth sawfish (Pristis pristis) is not only #1 on the EDGE sharks and rays list, but is also the highest ranking  EDGE species across all the different animal groups ranked, including corals, reptiles, amphibians, mammals and birds [Credit: (c) Simon Fraser University]

The new list revealed today (4 December) ranks the world's 50 most Evolutionarily Distinct and Globally Endangered (EDGE) sharks, rays and chimeras - known collectively as Chondrichthyes.

These mythical-sounding (but very real) creatures have no bones in their bodies, only cartilage and appeared more than 400 million years ago, roaming the seas when dinosaurs lived. Each species on this list has few or no remaining close relatives, effectively representing distinct branches of the tree of life and making each of them truly irreplaceable. If they go extinct, we will have nothing like them left on the planet.

Topping the new list, at number one is the largetooth sawfish (Pristis pristis), which also holds the distinction of being the highest-ranking EDGE species in the world. Using an elongated snout (rostrum) lined with teeth on each side to slash at its prey, the large-tooth sawfish is facing threats from unsustainable fishing activities as it's often caught as by-catch in nets.

Despite the fearsome reputation of the great white shark and the well-recognised appearance of the hammerhead, sharks are one of the least-studied groups of animals - some so elusive they've never been captured on camera. Many of these species are threatened by targeted fishing, driven by a desire for shark fins or other body parts, as well as being unintentionally caught (bycatch).

Habitat degradation, due to coastal development, mangrove deforestation, water pollution and trawling, is also to blame for the steep decline in many of these populations. However, the new EDGE List gives conservationists another tool to identify and prioritise species where there is a most pressing need for action.

EDGE Sharks co-ordinator and marine biologist, Fran Cabada said: "Sharks, rays and chimeras - making up the cartilaginous fish, have been around since the age of the dinosaurs, but due to human activities, their modern relatives are facing threats all over the world. They're found in almost every aquatic environment and as many are apex predators, i.e., at the top of the food chain - they're crucial to maintaining healthy ecosystems.

Representative phylogeny tree (taxon-complete) of Chondrichthyes. Red dotes highlight nodes defining orders [Credit: Stein et al. (2018)/EDGE]

"Unfortunately, sharks have a bad image. This means people often can't see beyond the negative, and usually exaggerated stories, and don't understand just how threatened and important they are.

"The new EDGE Sharks and Rays list gives us the opportunity to highlight the most unique sharks and rays on our planet which are also the most endangered, so that we can target conservation efforts where it's needed most. Many are overlooked and poorly known, so conservation actions targeted at these survivors of ancient lineages should be prioritised."

ZSL's Marine and Freshwater Conservation Programme Manager, Dr. Matthew Gollock added: "The EDGE Sharks and Rays list comprises some of the most interesting and unique fish we have on this planet. The modern extinction of a single species from this list would cause the loss of millions of years of evolutionary history.

"Since 2013, we have been working in collaboration with partner organisations in the Canary Islands for the conservation of the angel shark (Squatina squatina), #5 in the EDGE list, increasing our knowledge of this species and working with divers, fishers and policymakers to improve management and policy.

"Our successes from this project have allowed us to expand our work to Wales, UK, where we have taken a similar stakeholder-lead approach to collect sightings and community memories of the angel shark in order to better understand and conserve this Critically Endangered species across its range."

First established in 2007, the EDGE of Existence programme has previously published lists for amphibians, birds, corals, mammals and reptiles. The EDGE lists provide conservationists worldwide with a scientifically rigorous method of focusing their conservation efforts on animals and plants that represent a significant amount of threatened evolutionary history.

ZSL's EDGE of Existence programme works with partners including the National Geographic Photo Ark and Fondation Segré to fund early-career conservationists striving to secure the future of EDGE species all around the world, through the EDGE Fellowship initiative. The first ever EDGE Fellowships on Sharks and Rays will begin in early 2019, implementing conservation actions for the largetooth sawfish and the pelagic thresher shark (Alopias pelagicus) in Asia.

For more information please see the original paper presenting ED values for these species.

Click here to explore the Top 50 EDGE Sharks and Rays List.

Click here for the latest EDGE Sharks and Rays List.

Source: Zoological Society of London [December 04, 2018]

A UMass Boston professor and his colleagues have published new research showing that feeding on human junk food may be altering the course of evolution in Darwin's finches.

Finches eat off a plate in an urban area of the Galapagos [Credit: K. Gotanda]

Assistant Professor of Evolutionary Biology Luis De León says feeding on human foods is weakening natural selection on ground finch beaks, which is what drives the formation of new species in the wild. These findings, published in the journal Evolutionary Applications, suggest that the seemingly harmless activity of feeding birds might be altering the course of evolution in the iconic Darwin’s finches in the Galápagos islands.

“If we continue to feed finches, we’re not only affecting the individual species, but the processes that lead to the formation of new species,” De León said. “We’re getting in the way of evolution.”

Galápagos finches are famed for being the inspiration behind Charles Darwin’s pioneering work on evolution. They are an example of adaptive radiation, an evolutionary process that produces new species from a single, rapidly diversifying lineage. Their common ancestor arrived on the Galápagos about two million years ago, and since then Darwin's finches have evolved into more than a dozen recognized species differing in body size, beak shape, and feeding behavior.

De León and fellow researchers from UMass Amherst, Universidad San Francisco de Quito, McGill University, and Norwegian University of Science and Technology were on Santa Cruz Island when they found two forms of medium ground finches — a small and large version — while studying beak size at an isolated, pristine site.

When they repeated the same set of measurements at a nearby urban site, the distinction between the two beak sizes was not present. Studying data collected by other researchers in the 1970s, the researchers could see the two types of medium ground finches had been present in the area before, but something had changed in the last 40-50 years.

They hypothesized that the change might have to do with urbanization and the rapidly increasing human population in that area. In particular, the introduction of novel foods brought by humans.

Finches eat from an egg crate left by the researchers [Credit: University of Massachusetts Boston]

Using egg crates filled with natural seeds and human junk food — chips, cookies, and rice — the researchers tested to see if the finches were in fact feeding on human food and what their preference was, weighing the food before and after to see how much was eaten.

De León said they found that finches in the urban area were almost exclusively feeding on human food. When the experiment was repeated at an isolated site in nature, the finches ignored the trays.

They found that "urban" finches feed on human junk foods, and in fact prefer these foods over their natural diet. This indicates that ongoing urbanization in the Galápagos is eroding the ecological differences that originally drove the formation of species in Darwin's finches.

“In contrast to their natural diet, the finches are changing their diet to human junk food,” De León said. “We know one way finches diversify and become new species is by specializing in different food types. All three or four species of ground finches at urban sites on Santa Cruz Island seem to be converging onto the same junk food diet. If that’s the case, the selection pressures that would be naturally  keeping them apart would be weakening, possibly leading to the collapse of the adaptive radiation of ground finches.”

Researchers also found a strong preference for human foods at EG Beach, a non-urban site visited by tourists located 12 kilometers away from the town of Puerto Ayora. This suggests that human behavior, rather than human population density, is the main driver of finches’ preference for human food, expanding the impacts of urbanization beyond city centers.

Now that the researchers know that finches are changing their diets to human junk food, they need to look at the consequences for the actual evolution of the species on this island.

“When thinking about preserving biodiversity in general, we often focus on preserving individual species,” he said. “What we show with this work is we also need to consider preserving the processes that lead to the formation of species.”

Assistant Professor of Evolutionary Biology Luis De León studies Darwin's finches [Credit: University of Massachusetts Boston]

De León and a PhD student will return to the Galapagos in January.

De León said they will continue to do more genetic analysis, looking at whether there is an increase in gene flow across the four species of ground finch. Now that the birds are eating the same diet, researchers want to know if they are also interbreeding.

Elaine Montes, a second-year PhD student at UMass Boston who is working with De León, will look at the physiological consequences of human junk food on Galapagos finches by analyzing telomeres, a long chain of repetitive DNA at the end of every chromosome that can shorten due to stress and aging.

“We want to see whether they have a shorter life span than birds in nature,” he said.

De León has worked at UMass Boston for two years. He received his PhD at McGill University, where he started his work on Galapagos finches 14 years ago.

“It’s a fascinating place. Every species is so unique; it captures your imagination. You can imagine how Darwin was fascinated by looking at all those species,” he said. “I feel privileged to essentially walk in Darwin’s footsteps.”

Author: Crystal Valencia | Source: University of Massachusetts Boston [December 03, 2018]

Jellyfish undergo an amazing metamorphosis, from tiny polyps growing on the seafloor to swimming medusae with stinging tentacles. This shape-shifting has served them well, shepherding jellyfish through more than 500 million years of mass extinctions on Earth.

Jellyfish are an ancient and successful group of animals. An in-depth look at the genome of the moon jelly, Aurita aurelia, shows that early jellyfish likely repurposed an existing set of genes to transition between polyp and swimming life stages [Credit: Alexander Vasenin/WikiCommons]

"Whatever they're doing has really worked for them," said David Gold, an assistant professor of paleobiology in the UC Davis College of Letters and Science.

The first in-depth look at the genome of a jellyfish -- the moon jelly Aurelia aurita -- reveals the origins of this successful survival strategy. The Aurelia genome, published online in the journal Nature Ecology and Evolution, indicates early jellyfish recycled existing genes to morph from polyp to medusa. The results suggest animals can radiate into new niches and forms fairly easily.

"These findings provide further evidence that evolution doesn't necessarily make the genetic code more complex," said Gold, a lead researcher on the genome study. "Jellyfish can build a big, complex life history using many of the same genes found in simpler animals."

The research team was led equally by Gold, who performed much of the work as a postdoctoral fellow at the California Institute of Technology, and by Takeo Katsuki, a project scientist at the Kavli Institute for Brain and Mind at UC San Diego.

The genome: a multi-use tool

Jellyfish come from one of the oldest branches on the animal family tree, the phylum Cnidaria, which includes corals and anemones. Jellyfish were probably the first muscle-powered swimmers in the open ocean. They appeared in the late Precambrian Era, a period of major geologic and ecological changes that preceded the Cambrian explosion of animal life.

At some point in their evolution, jellyfish gained the ability to transition from a stationary polyp to a swimming medusa. The transition involves major changes in the jellyfish nervous system, muscles and weaponry, aka the stinging cells called cnidocytes. To accomplish this, the medusa life stage often co-opts existing developmental gene networks and cell types present in polyps, the researchers found. In addition, Aurelia appears to pattern its different life stages using many of the same genes found in animals such as fruit flies and humans, the study reports. (all of these animals share a common ancestor, albeit an ancient one.)

There is a second, more controversial explanation for what the scientists found in the jellyfish genome. Perhaps the similarities between the moon jellyfish genome and "higher" animals demonstrates that the Cnidaria originally had a medusa life stage, which animals like corals and sea anemones lost.

"Our results can't distinguish between these two scenarios," said Gold. If the second hypothesis turns out to be correct, "Swimming, carnivorous animals may be even older than we think." In addition to questions of evolution, the Aurelia genome will prove valuable in many other areas of biology, Gold said. Aurelia is an important model for studying the development and function of nervous systems, and can offer insights into animal wound healing and regeneration. Moon jellies are also a major culprit in environmentally and economically damaging jellyfish blooms, which are becoming more common. For example, giant swarms of moon jellies have clogged water-intake pipes, forcing the shutdown of nuclear plants in Florida and Sweden. An improved understanding of Aurelia genetics could offer new ideas for controlling the blooms.

"In many ways, the ancient oceans in the late Precambrian are very much like what the modern oceans will look like in the near future," Gold said "meaning studying how jellyfish evolved in the past can tell us about their potential impact on the future."

Source: University of California - Davis [December 03, 2018]

The research, led by the University of Plymouth, examined the uptake of nanoparticles by a commercially important mollusc, the great scallop (Pecten maximus). After six hours exposure in the laboratory, billions of particles measuring 250nm (around 0.00025mm) had accumulated within the scallop's intestines. However, considerably more even smaller particles measuring 20nm (0.00002mm) had become dispersed throughout the body including the kidney, gill, muscle and other organs.

These are some of the scallops used as part of the current research [Credit: University of Plymouth]

The study is the first to quantify the uptake of nanoparticles at predicted environmentally relevant conditions, with previous research having been conducted at far higher concentrations than scientists believe are found in our oceans.

Dr Maya Al Sid Cheikh, Postdoctoral Research Fellow at the University of Plymouth, led the study. She said: "For this experiment, we needed to develop an entirely novel scientific approach. We made nanoparticles of plastic in our laboratories and incorporated a label so that we could trace the particles in the body of the scallop at environmentally relevant concentrations. The results of the study show for the first time that nanoparticles can be rapidly taken up by a marine organism, and that in just a few hours they become distributed across most of the major organs."

Professor Richard Thompson OBE, Head of the University's International Marine Litter Research Unit, added: "This is a ground breaking study, in terms of both the scientific approach and the findings. We only exposed the scallops to nanoparticles for a few hours and, despite them being transferred to clean conditions, traces were still present several weeks later. Understanding the dynamics of nanoparticle uptake and release, as well as their distribution in body tissues, is essential if we are to understand any potential effects on organisms. A key next step will be to use this approach to guide research investigating any potential effects of nanoparticles and in particular to consider the consequences of longer term exposures."

A scan showing particles accumulated within the scallop's gills (GI), kidney (K), gonad (GO), intestine (I), hepatopancreas (HP) and muscle (M) [Credit: University of Plymouth]

Accepted for publication in the Environmental Science and Technology journal, the study also involved scientists from the Charles River Laboratories in Elphinstone, Scotland; the Institute Maurice la Montagne in Canada; and Heriot-Watt University.

It was conducted as part of RealRiskNano, a £1.1million project funded by the Natural Environment Research Council (NERC). Led by Heriot-Watt and Plymouth, it is exploring the effects which microscopic plastic particles can have on the marine environment.

In this study, the scallops were exposed to quantities of carbon-radiolabeled nanopolystyrene and after six hours, autoradiography was used to show the number of particles present in organs and tissue.

It was also used to demonstrate that the 20nm particles were no longer detectable after 14 days, whereas 250nm particles took 48 days to disappear.

Ted Henry, Professor of Environmental Toxicology at Heriot-Watt University, said: "Understanding whether plastic particles are absorbed across biological membranes and accumulate within internal organs is critical for assessing the risk these particles pose to both organism and human health. The novel use of radiolabelled plastic particles pioneered in Plymouth provides the most compelling evidence to date on the level of absorption of plastic particles in a marine organism."

Source: University of Plymouth [December 03, 2018]