Carbon Chemist

Tag: fossils

  • Ancient ichthyosaur found on UK beach may be the largest marine reptile ever

    Ancient ichthyosaur found on UK beach may be the largest marine reptile ever

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    Illustration of an Ichthyotitan severnensis carcass washed up on a beach

    Sergey Krasovskiy

    The 200-million-year-old fossilised remains of an ancient ichthyosaur, unearthed on a beach in south-west England, may be part of the largest marine reptile ever found.

    In 2020, amateur fossil hunters stumbled across a giant chunk of bone at Blue Anchor beach in Somerset. Upon further inspection, Dean Lomax at the University of Manchester, UK, and his colleagues quickly realised that it was a jawbone fragment of a giant ichthyosaur – a kind of reptile that roamed the oceans between 250 and 90 million years ago.

    Subsequent digs at the beach have uncovered 11 more fragments, allowing the team to partially piece together a bone that sits in the back of the jaw called a surangular.

    This latest discovery comes after a 2018 report that described a similar ichthyosaur jawbone found on a different Somerset beach. At the time, the team didn’t have enough evidence to determine its species.

    “It was very clear that this was another one of these giant jawbones,” says Lomax. “So I was very, very excited.”

    After comparing the partial surangular with the complete ones of other ichthyosaurs, the team estimates that the whole bone was at least 2 metres long – putting the animal’s body length at around 20 to 25 metres.

    “We’re dealing with something truly enormous,” says Lomax. “It would certainly represent the largest marine reptile formally described.”

    The nature of the surangular, which matches the one reported in 2018, means both fossils must have belonged to a previously undescribed species of ichthyosaur, says Lomax. The team have named it Ichthyotitan severnensis, meaning the giant fish lizard of the river Severn.

    The remains date to around 202 million years ago, just before a major global extinction event that wiped out many species, including many giant ichthyosaurs.

    “They are quite literally the last giants,” says Lomax. “No ichthyosaurs got anywhere near this size again.”

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  • Extinct freshwater dolphin from the Amazon was largest of all time

    Extinct freshwater dolphin from the Amazon was largest of all time

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    Artistic reconstruction of Pebanista yacuruna

    An artistic reconstruction of Pebanista yacuruna in the murky waters of the Peruvian proto-Amazon

    Jaime Bran

    The Amazon basin was once home to freshwater dolphins that grew up to 3.5 metres long – making them the largest river dolphins known to science.

    Researchers made the surprise discovery during a 2018 expedition in Peru, says Aldo Benites-Palomino at the University of Zurich in Switzerland. The team saw the animal’s fossilised skull poking out of a river embankment and knew right away it was a dolphin. Close analysis confirmed the giant skull was unlike any ever found.

    The researchers have now named the new species Pebanista yacuruna. The name honours a mythical aquatic people – the Yacuruna – believed to inhabit underwater cities in the Amazon basin.

    The 16-million-year-old fossil was unearthed in a region that was once covered by a lake that was “insanely big – almost like a little ocean in the middle of the jungle”, says Benites-Palomino. Based on the small size of the ancient dolphin’s eye sockets and its large teeth, he says P. yacuruna was probably a predator with poor eyesight. It relied heavily on echolocation to find fish. “We know that it was living in really muddy waters because its eyes started to reduce in size,” says Benites-Palomino.

    Because the fossil was found in the Amazon basin, the researchers expected its closest living relatives to be modern Amazon river dolphins. Instead, they found P. yacuruna was more closely related to river dolphins of South Asia. Like them, this ancient species has raised crests on its skull that improved its ability to echolocate.

    P. yacuruna may have been driven extinct during a broader ecological shift, says Benites-Palomino. “Around 11 to 12 million years ago, this mega wetland system started to drain, giving way to the modern Amazon. A lot of species disappeared at that moment, and that might also have been the fate of this giant dolphin.”

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  • Mammoth carcass was scavenged by ancient humans and sabre-toothed cats

    Mammoth carcass was scavenged by ancient humans and sabre-toothed cats

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    A southern mammoth skeleton found in Spain bears cut marks from stone tools and bite marks from carnivore teeth, suggesting that both hominins and felids feasted on its meat

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  • When does a bone become a fossil?

    When does a bone become a fossil?

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    A reconstruction of the skull of a Homo naledi child

    Brett Eloff Photography/Wits University

    This is an extract from Our Human Story, our newsletter about the revolution in archaeology. Sign up to receive it in your inbox for free every month.

    The word “fossil” is one that I type out rather frequently. You’ll often read stories about new hominin remains in which they are described as fossils. But hang on. Fossils take a long time to form, so how old does a human bone or tooth need to be before it counts as a fossil? Should…

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  • Perucetus colossus: An ancient whale claimed the title of heaviest animal ever in 2023

    Perucetus colossus: An ancient whale claimed the title of heaviest animal ever in 2023

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    An artist’s impression of Perucetus colossus

    Alberto Gennari

    In August, the blue whale was cut down to size. Once known as the heaviest animal to have ever existed, that title has now been claimed by a gargantuan species of ancient whale discovered in Peru. The oversized beast, dubbed Perucetus colossus, has delighted people around the world.

    The story of P. colossus began in 2010, when Eli Amson at the State Museum of Natural History Stuttgart in Germany and his colleagues unearthed the partial skeleton of an enormous whale in southern Peru. The…

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  • Triassic ichthyosaur was super-predator that may have been largest ever animal

    Triassic ichthyosaur was super-predator that may have been largest ever animal

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    Ichthyosaur

    Artist’s impression of Stenopterygius quadriscissus, an ichthyosaur

    dotted zebra / Alamy Stock Photo

    PREHISTORIC Earth was a place of monsters. There were 2.5-metre-long millipedes, flying reptiles with 11-metre wingspans and snakes that weighed over a tonne. But if it is the biggest animal of all time you are looking for, conventional wisdom says you don’t need to step back in time. The blue whale is known to reach 30 metres in length and to weigh 199 tonnes. Nothing else in more than half a billion years of animal evolution comes close, not even the largest dinosaur.

    Conventional wisdom might be wrong. The fossil record may be concealing an animal that was even bigger than a blue whale. For decades there has been a slow trickle of evidence that a truly enormous super-predator swam the seas between 200 and 250 million years ago. Now, a string of discoveries and reanalysis of previous findings has dramatically bolstered the case.

    The implications are far-reaching. We don’t know exactly what this huge animal looked like and it doesn’t even have a name. We have, however, begun to work out how such a gigantic creature could feed itself in the prehistoric seas. Confirmation that it outgrew the blue whale would tell us that we may have drastically underestimated how large toothed carnivores can grow. More than that, the discovery that such leviathans appeared shortly after the most devastating mass extinction in Earth’s history suggests we may need to rethink the factors that drive evolution on such an epic scale.

    When dinosaurs ruled the land, several groups of marine reptiles dominated…

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