US EditionBus-Sized Mosasaur Hunted North Dakota Rivers 66 Million Years Ago
Isotopic analysis of a mosasaur tooth found in North Dakota shows freshwater hunting behavior linked to shrinking seaway and reduced salinity, researchers said.
- On December 11, BMC Zoology published findings reporting that at least one mosasaur species may have hunted upstream into freshwater rivers, based on a tooth found in the Hell Creek formation, Montana.
- The Hell Creek formation, Montana, hosts rich Upper Cretaceous fossils and included rivers linking into the Western Interior Seaway around 66 million years ago.
- Researchers matched the tooth's ridges to Prognathodon , and tooth enamel isotopic analysis showed freshwater signatures with no signs of postmortem movement in present-day North Dakota.
- Paleontologists infer seaway salinity declined, enabling mosasaurs to adapt river-channel hunting behavior, likened to Crocodylus porosus, forcing river-adjacent animals to avoid water.
- Although local material is limited, older specimens from the Western Interior Seaway show freshwater traits, and mosasaurs often reached 30 to 40 feet as apex predators.
17 Articles
17 Articles
Fearsome Marine Predators Prowled Ancient Rivers, Too
A dental discovery in an ancient riverbed in North Dakota is shedding light on one of the most fearsome reptiles to ever swim the seven seas—the mosasaur. Nautilus Members enjoy an ad-free experience. Log in or Join now . You may remember the massive mosasaur from the movie Jurassic World. The behemoth was kept in an expansive sea pen and forced to perform for parkgoers before taking down a genetically modified Tyrannosaurus rex (called Indomin…
Tooth fossil reveals secrets of 40ft prehistoric sea monster
A 66-million-year-old tooth unearthed in North Dakota revealed the secrets of mosasaurs, a huge 40ft ocean predator. The findings revealed that the fearsome marine reptile ventured far from its natural habitat to stalk prey in freshwater rivers.The fossil, discovered in the renowned Hell Creek Formation, was analysed by an international research team whose findings were published yesterday in the journal BMC Zoology.Scientists had previously bel…
The Proof Is in One Ancient Tooth: Ancient Lizards Swam Not only in the Sea, but Also in Fresh Water
Mosasaurs, ancient lizards long believed to be marine animals, could also live in freshwater. A 66-million-year-old tooth...
Palaeontology: Ancient tooth suggests ocean predator could hunt in rivers
A 66-million-year-old tooth discovered in North Dakota, USA, suggests that some mosasaurs — extinct lizard-like reptiles that could grow up to 12 metres long — may have hunted in rivers as well as seas. The authors suggest that the findings, which are published in BMC Zoology...
Coverage Details
Bias Distribution
- 60% of the sources are Center
Factuality
To view factuality data please Upgrade to Premium
