Chilled out or worked up? Most of us can pick up pretty quickly on another human’s state of emotional arousal. But Charles Darwin hypothesized that understanding emotional expression across species went way, way back, all the way to the earliest terrestrial vertebrates (that’s 350 million years, give or take), and that it was crucial for survival.
After all, it’s kinda helpful to know if those monkeys in the trees are just yammering on about nothing or freaking out about the lion they see sneaking up on you.
Today, in an intriguing study, researchers have the first evidence that Darwin was right. The new study hints that all terrestrial vertebrates — you, this alligator, every dead dinosaur, birds and yeah, those monkeys in the trees and the sneaky lion, too — evolved a universal signaling system, a form of communication that we still retain, and might even put to good use.
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