When the same solution is devised for a problem in different scenarios, i.e., convergent evolution, there’s something going on. And this has a bonus: it involves charismatic dinosaurs:
“The neat thing is that we found the body plan [of Meraxes gigas] is surprisingly similar to tyrannosaurs like T. rex,” said [Peter] Makovicky, one of the principal authors of the study and a professor in the University of Minnesota N.H. Winchell School of Earth and Environmental Sciences. “But, they’re not particularly closely related to T. rex. They’re from very different branches of the meat-eating dinosaur family tree. So, having this new discovery allowed us to probe the question of, ‘Why do these meat-eating dinosaurs get so big and have these dinky little arms?’”
With the statistical data that Meraxes provided, the researchers found that large, mega-predatory dinosaurs in all three families of therapods grew in similar ways. As they evolved, their skulls grew larger and their arms progressively shortened.
The possible uses of the tiny forelimbs in T. rex and other large carnivorous dinosaurs have been the topic of much speculation and debate.
“What we’re suggesting is that there’s a different take on this,” Makovicky said. “We shouldn’t worry so much about what the arms are being used for, because the arms are actually being reduced as a consequence of the skulls becoming massive. Whatever the arms may or may not have been used for, they’re taking on a secondary function since the skull is being optimized to handle larger prey.” [University of Minnesota News and Events]
Gotta love the painting:
By Carlos Papolio – Own work, CC BY-SA 4.0, Link.
At 36 feet long, that’s big enough to scare the hell out of me.
