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Categories: Biology: Marine, Paleontology: Fossils

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Scientists have discovered a new species of mosasaur, a sea-dwelling lizard from the age of the dinosaurs, with strange, ridged teeth unlike those of any known reptile. Along with other recent finds from Africa, it suggests that mosasaurs and other marine reptiles were evolving rapidly up until 66 million years ago, when they were wiped out by an asteroid along with the dinosaurs and around 90% of all species on Earth.

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Little is known about the ecological relationship of Vibrio bacteria with Sargassum. Evidence also is sparse as to whether vibrios colonizing plastic marine debris and Sargassum could potentially infect humans. As summer kicks off and efforts are underway to find solutions to repurpose Sargassum, could these substrates pose a triple threat to public health? Results of a study representing the first Vibrio spp. genome assembled from plastic finds Vibrio pathogens have the unique ability to 'stick' to microplastics, harboring potent opportunistic pathogens.

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A newly published artificial intelligence (AI) algorithm is allowing researchers to quickly and accurately estimate coastal fish stocks without ever entering the water.

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In testing the genetic material of current populations in Africa and comparing against existing fossil evidence of early Homo sapiens populations there, researchers have uncovered a new model of human evolution -- overturning previous beliefs that a single African population gave rise to all humans.

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Researchers investigated how the jaw shape of sharks has changed over the course of evolution. Their conclusion: in the most widespread shark species, the jaws show relatively little variation in shape over millions of years; most variable jaws were found for deep-sea sharks.

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Inspired by clam fishermen reports, researchers used passive acoustic telemetry to gauge the interactions between two highly mobile rays. They monitored the tagged rays in the wild over two years to see how often and when they visited clam leases, designated underwater locations used to produce hard clams of all sizes from littlenecks to chowders. Results provide both good news and bad news for clammers. Rays spent even more time in these clam lease sites than clammers reported or suspected, but it's not necessarily where they prefer hanging out.

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A new study has found humpback whales sing louder when the wind is noisy, but don't have the same reaction to boat engines.

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In the autumn, when right whales swim towards the coasts of South Africa, they ought to be fat and stuffed full. But in recent years, they have become thinner because their food is disappearing with the melting sea ice.

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Throughout the ocean, billions upon billions of plant-like microbes make up an invisible floating forest. As they drift, the tiny organisms use sunlight to suck up carbon dioxide from the atmosphere. Collectively, these photosynthesizing plankton, or phytoplankton, absorb almost as much CO2 as the world’s terrestrial forests. A measurable fraction of their carbon-capturing muscle comes from Prochlorococcus — an emerald-tinged free-floater that is the most abundant phytoplankton in the oceans today. New research suggests the microbe's ancient coastal ancestors colonized the ocean by rafting out on chitin particles.

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Scalloped hammerhead sharks hold their breath to keep their bodies warm during deep dives into cold water where they hunt prey such as deep sea squids. This discovery provides important new insights into the physiology and ecology of a species that serves as an important link between the deep and shallow water habitats.

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There have been heated debates over the size of Jurassic animals. The speculation was set to continue, but now a chance discovery in an Oxfordshire museum has led to palaeontologists publishing a paper on a Jurassic species potentially reaching a whopping 14.4 meters -- twice the size of a killer whale.

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Surveying the body sizes of Earth's living organisms, researchers found that the planet's biomass -- the material that makes up all living organisms -- is concentrated in organisms at either end of the size spectrum.

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A fossil arthropod entombed in 100-million-year-old Burmese amber has been identified as a new genus and species of froghopper, known today as an insect with prodigious leaping ability in adulthood following a nymphal stage spent covered in a frothy fluid.

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Around 500 million years ago life in the oceans rapidly diversified. In the blink of an eye -- at least in geological terms -- life transformed from simple, soft-bodied creatures to complex multicellular organisms with shells and skeletons. Now, research has shown that the diversification of life at this time also led to a drastic change in the chemistry of Earth's crust -- the uppermost layer we walk on and, crucially, the layer which provides many of the nutrients essential to life.

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One of the basic and crucial embryonic processes to unfold in virtually every living organism is the formation of hollow, tubular structures that go on to form blood vessels or a digestive tract, and through branching and differentiation, complex organs including the heart and kidneys. This study illuminates fundamental design principles of tubulogenesis for all chordates, including mammals.

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Even without body parts that allowed for movement, new research shows -- for the first time -- that some of Earth's earliest animals managed to be picky about where they lived.

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Phytosterols are good for your health, but humans and other animals are not able to make them themselves, only plants can. To acquire phytosterols, humans are increasingly turning to supplements, green smoothies, or a Mediterranean diet with plenty of plant-based foods. Researchers have now discovered that tiny gutless worms from the Mediterranean can synthesize phytosterols on their own. Their study provides evidence that many other animals also have the genes needed to make their own phytosterols.

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For decades, scientists have used the amount of seaweed at the ocean's surface as a proxy for the health of coral reefs below. However, a new global study of more than 1,200 marine locations over a 16-year period reveals that this approach has been misleading -- and may even have hidden signs of reef stress.

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An international research team has for the first time successfully isolated ancient human DNA from a Paleolithic artefact: a pierced deer tooth discovered in Denisova Cave in southern Siberia. To preserve the integrity of the artefact, they developed a new, nondestructive method for isolating DNA from ancient bones and teeth. From the DNA retrieved they were able to reconstruct a precise genetic profile of the woman who used or wore the pendant, as well as of the deer from which the tooth was taken. Genetic dates obtained for the DNA from both the woman and the deer show that the pendant was made between 19,000 and 25,000 years ago. The tooth remains fully intact after analysis, providing testimony to a new era in ancient DNA research, in which it may become possible to directly identify the users of ornaments and tools produced in the deep past.

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Traces of sex hormones extracted from a woolly mammoth's tusk provide the first direct evidence that adult males experienced musth, a testosterone-driven episode of heightened aggression against rival males, according to a new study.