Horizontal pupils for a bigger field of vision if you’re a prey animal. They need to see as much as they can to spot predators.
And the vertical ones are basically the opposite and allow for better night vision. Like cats have them for that purpose. It allows their field of vision to basically hone in on prey. I’m butchering it but that’s the gist.
vertical pupils let animals judge distance better by telling what’s in and out of focus. This effect only works low to the ground, so only small-to-medium predators who hunt on the ground tend to have them.
Horizontal pupils let animals see a wider field of view, so animals who need to spot predators tend to have this adaptation.
The bigger your pupil, the more light gets into your eye, but also the shallower your depth of field (can’t focus on near and far at the same time, and need more accurate focus to have stuff not be blurry).
When your pupil is not a circle, you can get some benefit of each option, in different directions. The vertical slits in a cats eye will let it judge depth more easily, and make it easier to tell where something is located left to right.
Animals with horizontal pupils are mostly using their vision to detect incoming predators, so they mostly need to know whether or not they need to run, rather than have accurate tracking. They do have wider fields of vision, but most of this comes from the placement of their eyes on the head and the lens rather than the shape of the pupil.
Predators tend to have vertical pupils so they can focus in on their prey. The vertical pupils allow for a thinner, but more focused field of view. Alternatively, prey animals have horizontal pupils because they need as wide a field of view to see predators. They don’t need to focus on the predators as much, just need to know when to run for it.
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Horizontal pupils for a bigger field of vision if you’re a prey animal. They need to see as much as they can to spot predators.
And the vertical ones are basically the opposite and allow for better night vision. Like cats have them for that purpose. It allows their field of vision to basically hone in on prey. I’m butchering it but that’s the gist.
vertical pupils let animals judge distance better by telling what’s in and out of focus. This effect only works low to the ground, so only small-to-medium predators who hunt on the ground tend to have them.
Horizontal pupils let animals see a wider field of view, so animals who need to spot predators tend to have this adaptation.
The bigger your pupil, the more light gets into your eye, but also the shallower your depth of field (can’t focus on near and far at the same time, and need more accurate focus to have stuff not be blurry).
When your pupil is not a circle, you can get some benefit of each option, in different directions. The vertical slits in a cats eye will let it judge depth more easily, and make it easier to tell where something is located left to right.
Animals with horizontal pupils are mostly using their vision to detect incoming predators, so they mostly need to know whether or not they need to run, rather than have accurate tracking. They do have wider fields of vision, but most of this comes from the placement of their eyes on the head and the lens rather than the shape of the pupil.
Predators tend to have vertical pupils so they can focus in on their prey. The vertical pupils allow for a thinner, but more focused field of view. Alternatively, prey animals have horizontal pupils because they need as wide a field of view to see predators. They don’t need to focus on the predators as much, just need to know when to run for it.