Scallops have dozens of tiny eyes lining the edge of their shells. These aren't your run-of-the-mill eyes, though. They're more like little mirrors that can actually form images. Their eyes can pick up shadows or sudden changes in light, giving them a heads-up when a predator is nearby.

Each eye has a concave mirror made of guanine crystals that focuses light onto not one, but two separate retinas. One retina detects movement, and the other helps create a crude image of the world around them. It's a level of sophistication most people wouldn't expect from a clam-looking creature.

Scallops can even swim short distances by rapidly clapping their shells, and their eyes help them figure out which way to go. It's like having a dozen little motion detectors. I already struggle with eye contact

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