Dinosaurs and alligators may both be reptiles, but the similarities were thought to be few and far between. Dinosaurs are commonly thought to have been warm-blooded, while alligators are cold-blooded, meaning they cannot regulate their own body temperatures.
Now, a new study suggests that both dinosaurs and animals have more in common than previously thought – their ability to hear.
The study, published in the Journal of Neuroscience, notes that alligators create the same type of neural maps of sound the way birds do, due in part to their common ancestor, the archosaur.
"We conclude that the available acoustic cues and the architecture of the acoustic system in early archosaurs led to a stable and similar organization in today's birds and crocodiles although physical features, like internally coupled ears, head size or shape, and audible frequency range, vary among the two groups," the researchers wrote in their study.
"Our research strongly suggests that this particular hearing strategy first evolved in their common ancestor," University of Maryland professor Catherine Carr said in a statement. "The other option, that they independently evolved the same complex strategy, seems very unlikely."
Carr and her team studied 40 different alligators and gave them earphones as they attempted to study how they identified sound. They played a variety of different tones and measured the response of a structure in their brain stems known as nucleus laminaris, which measures auditory signal processing.
From there, they were able to determine that the 'gators created neural maps that are very similar to barn owls and chickens.
"We know so little about dinosaurs," Carr said. "Comparative studies such as this one, which identify common traits extending back through evolutionary time add to our understanding of their biology."