Biodiversity gap T. Rex style

T. rex fossil. Image: UNM Biology Department

Seems T. Rex and significant other giant predators had a huge negative impact on biodiversity from hatchling to adult which was much more pervasive than the large predators of today as seem by a piece by Gizmodo describing just how tyrannical T. Rex and brethren were back in the day.

Large meat-eating dinosaurs took on the role of multiple species while growing up, resulting in a shocking lack of ecological diversity during the Mesozoic, according to new research.

Megatheropods—gigantic two-legged carnivores like Tyrannosaurus, Allosaurus, and Daspletosaurus—didn’t instantly dominate the ecological space belonging to monstrously huge dinosaurs. Like other dinosaurs, they hatched from eggs and had to survive while transitioning into adulthood. As a new research paper published in Science shows, these developmental stages weren’t just idle stepping stones for megatheropods; they were periods in which the dinosaurs, while juveniles, were still ecological forces to be reckoned with.

End result

“This study puts numbers on something we’ve suspected but haven’t really proven: that the biggest meat-eating dinosaurs filled different niches in the food chain as they grew from miniature hatchlings into adults bigger than buses,” Steve Brusatte, a paleontologist at the University of Edinburgh who’s not involved with the new research, said in an email.

The authors of the new study, led by Katlin Schroeder, a PhD candidate at the University of New Mexico, have proposed a new term to describe this phenomenon: “morphospecies.” It basically means that megatheropods, while maturing, growing, and changing their hunting habits, took on the role of multiple species.

“Morphospecies is a really nice term,” Holly Woodward, a paleontologist from Oklahoma State University who’s not affiliated with the new research, said in an email. “A juvenile T. rex for example is still a T. rex, but it’s carrying out the role of smaller carnivore species, without being a different species.”

Infographic showing the size distribution among meat-eating mammals and dinosaurs, with a glaring gap among mid-sized dinosaurs. Image: UNM Biology Department

Interesting without question.