Fish yawn, cough, and even burp. But they don’t get choked up.
Crying, says Monterey Bay Aquarium’s retired senior marine biologist Steve Webster, is an emotional response made only by big-brained mammals.
Crybabies are "self-aware and can reflect upon past events, make projections about future events and engage in lots of other complex cognitive behaviors," Webster said.
"Since fishes lack the parts of the brain that set us apart from the fishes — the cerebral cortex — I doubt very much that fishes engage in anything like crying," Webster told LiveScience. "And certainly they produce no tears, since their eyes are constantly bathed in a watery medium."
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