A mantis shrimp’s eye is a marvel. Our eyes use three types of colour receptor - red, green, and blue. A mantis shrimp has at least 12, plus sensors for ultraviolet and polarized light. For years, people said this meant mantis shrimp could see colours we couldn’t even imagine.
In 2014, scientists actually tested it. They trained mantis shrimp to pick between two colours, and found something surprising: they’re worse at telling similar colours apart than humans are. The 12 receptors aren’t for super-fine colour vision. They’re for super-FAST colour vision. A mantis shrimp doesn’t compare colours in its brain like we do - each receptor fires instantly, so the shrimp can snap-decide whether something is prey, predator, or rival in a flash.
Each of its compound eyes is split into three zones - like three eyes in one socket - and both eyes move independently. And the polarized light vision? Scientists think it’s how mantis shrimp send secret signals to each other that no predator can read.
