[Rockhounds] Dinosaurs Like T. Rex Were More Tyrannical Than We Realized

[Kreigh Tomaszewski]

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 <http://dx.doi.org/10.1126/science.abd9220> 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.

“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.”

https://gizmodo.com/dinosaurs-like-t-rex-were-more-tyrannical-than-we-real-1846353911