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Headline: RAW VIDEO: Was Nessie real? New evidence showed prehistoric monsters could live in freshwater
Caption: Could the Loch Ness monster have been real? Albeit living millions of years before the claimed sightings that have cemented its place in Scottish folklore, new research from scientists suggests so. More than 60 million years ago, mosasaurs were gigantic marine reptiles that roamed the seas. But until now they were thought to only be ocean-dwellers - ruling out its presence in rivers or, importantly, Scottish lochs. However, the new research suggests that mosasaurs were not strictly ocean-dwellers after all. In the final million years before their extinction, some appear to have taken up residence in freshwater rivers - a finding that has delighted scientists and inevitably revived playful comparisons with Britain’s most famous aquatic mystery. The evidence comes from a single, hefty tooth discovered in North Dakota in 2022. Found in a river deposit alongside fossils from a Tyrannosaurus rex and a crocodile-like reptile, the tooth belonged to a mosasaur that could have grown up to 11 metres long - roughly the size of a bus. Until now the prehistoric monster’s fossils had only been found in marine rocks, so its presence in a river setting raised eyebrows. How did a creature thought to rule the seas end up sharing space with land dinosaurs and river-dwelling predators? An international team of researchers from the US, Sweden and the Netherlands set out to answer that question using chemical clues locked inside the tooth itself. By analysing isotopes of oxygen, strontium and carbon preserved in the enamel, the scientists were able to reconstruct where the animal lived and what it ate. The results were striking. The tooth carried a chemical signature more typical of freshwater animals than marine ones. Compared with other known mosasaurs, it contained unusually high levels of lighter oxygen isotopes, alongside strontium ratios that also point away from saltwater. In short, this mosasaur had been spending its time in rivers. Carbon isotopes added another twist. While many mosasaurs show signs of deep diving in the ocean, this individual did not. Its chemical profile suggests it stayed closer to the surface - and may even have fed opportunistically on animals that fell into the river, including drowned dinosaurs. Two further mosasaur teeth found nearby, from slightly older rocks, showed similar freshwater signals. Together, the findings suggest that mosasaurs were adapting to river life in the closing chapter of the dinosaur age. Melanie During, one of the study’s corresponding authors says: “The isotope signatures indicated that this mosasaur had inhabited this freshwater riverine environment. When we looked at two additional mosasaur teeth found at nearby, slightly older, sites in North Dakota, we saw similar freshwater signatures. These analyses shows that mosasaurs lived in riverine environments in the final million years before going extinct.” At the time, North America was split by a vast inland sea known as the Western Interior Seaway. As freshwater input increased, this shallow sea gradually became less salty, eventually resembling today’s brackish-to-fresh waters of the Gulf of Bothnia. Scientists believe this created layered water conditions, with freshwater sitting on top of denser saltwater - a habitat well suited to air-breathing predators like mosasaurs. Unlike fish, mosasaurs had to surface to breathe, meaning they could thrive in the upper freshwater layers while avoiding saltier depths below. This ability to cope with changing conditions may explain how they were able to move into rivers as their world transformed. Such a shift is not without precedent. Modern river dolphins evolved from marine ancestors, while Australia’s saltwater crocodiles move easily between rivers and the open sea. In evolutionary terms, returning to freshwater can be simpler than adapting to life in the ocean in the first place. The North Dakota tooth belonged to a stocky, powerful type of mosasaur related to the genus Prognathodon - animals with massive heads, robust jaws and a reputation as opportunistic predators. Meeting one in a river would not have been for the faint-hearted. And while no one is suggesting that a mosasaur is lurking beneath the dark waters of Loch Ness today, the idea that bus-sized reptiles once hunted in freshwater does give a prehistoric twist to the legend of Nessie - as it has been often suggested that a possible candidate would be prehistoric reptiles that had somehow become cut off and survived in the Scottish loch. Sadly for monster hunters, mosasaurs vanished along with the dinosaurs 66 million years ago. But their newly discovered river-running habits show that these giants were even more adaptable - and more surprising - than previously thought.
Keywords: feature,photo,video loch ness monster,nessie,scotland,prehistoric,palaeontology,science
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