Debate heats up over swimming ability of bizarre-looking Spinosaurus

[Judi Lynn]

By Laura Geggel - Editor a day ago

Maybe the dinosaur Spinosaurus wasn't the Michael Phelps of swimming.



An illustration of a Spinosaurus wading in the water and hunting for fish.
(Image: © Nicholls2020)

The wild-looking Spinosaurus may not have been the Michael Phelps of dinosaurs, as was recently claimed, but rather more like a casual bathing beauty that preferred to wade gracefully in the shallow zone, a new study suggests.

That's not to say Spinosaurus couldn't swim: It could. But it wasn't the "highly specialized aquatic predator" that could efficiently chase prey through the water, as it was made out to be in a big 2020 study published in the journal Nature, the researchers of the new study said.

"Spinosaurus was probably a decent swimmer, and certainly a better swimmer than any other known large theropod [bipedal, mostly meat-eating dinosaurs]," study co-researcher Thomas Holtz, principal lecturer in vertebrate paleontology at the University of Maryland, told Live Science in an email. "But being a swimmer isn't the same thing as being a specialized aquatic pursuit predator."

Rather, Spinosaurus was probably like a modern-day heron or stork — wading into the water and sticking part of its head underwater as it fished for prey, but also opportunistically hunting on land for terrestrial animals or winged creatures, the researchers said.

More:
https://www.livescience.com/spinosaurus-dinosaur-mediocre-swimmer.html

[eppur_se_muova]

1. I was thinking that Spinosaurus had turned out to be the same as Deinocheirus. Apparently not.

https://www.fossilguy.com/gallery/vert/dinosaur/spinosaurus/types-of-spinosaurus.htm


Zofia Kielan-Jaworowska with the holotype specimen of Deinocheirus. She led the joint Polish-Mongolia expedition which discovered it. (Both Poles and Mongolians were circumventing Soviet overlordship to some extent by forming their own expedition without Russian involvement -- which would have meant Russians running everything.)
https://en.wikipedia.org/wiki/Deinocheirus#Classification


Both these fossil discoveries have fascinating parallel histories. In both cases fossils poached from the original site and sold on the black market were late recovered and led to nearly complete skeletons being restored. (I'm oversimplifying quite a bit here!)

It's weird that two genera with such unusual traits -- enormously long front limbs and sailbacks -- should be the product of parallel evolution. But it appears they did evolve in similar environments -- one in north Africa, the other in eastern Asia.