An Octopus pupil is rectangular
While most animals, including humans, have round pupils, the pupils of sheep, goats, octopuses and toads are of rectangular shape.
The reason these animals have rectangular pupils is because this is what helps them avoid predators.
Rectangular pupils tend to get very narrow during day time, which gives animals a greater accuracy of depth perception in their peripheral vision. Traditionally seen as prey, thanks to their eyes these animals are able to avoid predators.
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