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New Study Reveals Sharks' Tonic Immobility Mystery

6/25/2025

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Summary

Story summary

Sharks and rays exhibit a fascinating freeze response known as tonic immobility when flipped upside down. Initially believed to be a defense mechanism against predators, new research suggests it might instead be an evolutionary leftover, existing in certain species without a clear function. This discovery unveils the intricate layers of animal behavior.

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Story summary

Sharks and rays exhibit a fascinating freeze response known as tonic immobility when flipped upside down. Initially believed to be a defense mechanism against predators, new research suggests it might instead be an evolutionary leftover, existing in certain species without a clear function. This discovery unveils the intricate layers of animal behavior.