The giant dinosaur Spinosaurus acted like modern herons or storks and caught fish and other prey in the water from the sides of the water or in shallow water, but also occasionally searched for rural prey and removed, according to new research by paleontologists from Queen Mary University of London , the University of Maryland and the National Museum of Natural History in Washington.
Able to catch both prey in the water and on land, and perhaps an opportunistic scavenger, adult Spinosaurus probably took water prey by standing in shallow water or at the edge of water bodies. Image credit: Robert Nicholls.
Spinosaurus is a giant teropod dinosaur that lived about 95 million years ago in present-day North Africa (Cretaceous).
Since its discovery in 1915, the biology and behavior of this ancient creature has amazed paleontologists worldwide.
It has recently been argued that Spinosaurus was largely a striving predator of water trials, and used its large tail to swim and actively pursue fish in the water.
The new study disputes this view and suggests that although it was probably fed out of the water and possibly swam, it was not well adapted to the life of a predator in the water.
‘The biology and ecology of Spinosaurus paleontologists have been plagued for decades, ”said lead author Dr David Hone, a paleontologist at Queen Mary University in London.
“Some recent studies have suggested that fish are actively chased into water, but although they could swim, they would not have been fast or efficient enough to do so effectively.”
“Our findings suggest that the wading idea is much better supported, even if it is slightly less exciting.”
Dr. Hone and his colleague, Dr Tom Holtz, compare the characteristics of Spinosaurus with the skulls and skeletons of other dinosaurs and various living and extinct reptiles that lived on land, in the water or did both.
They found that although there was several pieces of evidence that contradicted the concept of predators in the water, no one contradicted the fan-like model, and that different lines of evidence actively supported it.
‘Spinosaurus was a bizarre animal, even by dinosaur standards, and unlike anything that lives today, it will always be difficult to understand its ecology, “Dr. Holtz said.
“We tried to use the evidence we had to get the best out of it. And what we found does not match the characteristics that one would expect in a predator in the water such as an otter, sea lion or short-necked plesiosaurus. ‘
Spinosaurus had fewer tail muscles than a crocodile, and because of its size it would have much more resistance in the water.
“Crocodiles are excellent in water compared to terrestrial animals, but are not as special to aquatic life and are not able to actively chase after fish,” said Dr. Hone said.
‘As Spinosaurus had less muscle on the tail, less efficiency and more resistance, then it’s hard to see how these dinosaurs could chase fish in a way that crocodiles could not. ”
‘While our study gives us a clearer picture of the ecology and behavior of Spinosaurus, there are still many outstanding questions and details to explore for future study, and we should continue to review our ideas as we gather further evidence and data on these unique dinosaurs. This will not be the last word on the biology of these amazing animals. ”
The team’s report was published online in the journal Palaeontologia Electronica.
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David WE Hone & Thomas R. Holtz, Jr. 2021. Evaluation of the ecology of Spinosaurus: Coastal generalist or specialist in the pursuit of water? Palaeontologia Electronica 24 (1): a03; doi: 10.26879 / 1110