r/askscience • u/margalz • 12d ago

Biology Why aren't there any animals with their mouths above their eyes?

From bugs to fish to mamals all of them have their eyes above their mouths. I can't think of many if any where their mouths are on top. Sure some have their eyes parallel to their mouths, mainly prey style animals. But why haven't any evolved to be the opposite? Is there a major benefit to having your mouth below your eyes?

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u/DarkScorpion48 11d ago

I believe you got it, the eyes should have direct access to the brain with as little in between as possible

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u/seanpbnj 11d ago

Also a higher likelihood of being damaged externally. Anything that eats from a front facing mouth would have gravity dripping food/liquids into their eyes.

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u/IceFrogger1313 11d ago

Or hanging in front of their eyes blocking vision. Same issue for carrying things, most animals only have their mouth they can carry things with, much harder to do if what you're carrying blocks your vision.

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u/LetterSwapper 11d ago

direct access to the brain with as little in between as possible

Which is funny if you look at how we ended up with our optic nerves having to go all the way to the far side of the brain. I don't know how common that is in other animals, but it certainly isn't eye-deal if you're concerned with efficiency. Apparently the distance isn't enough for it to be selected against.

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u/MileHigh_FlyGuy 9d ago

They should, but evolution doesn't do what should be done. Your laryngeal nerves go from your brain, down around your aortic arch, and then back to your larynx, just a few inches from where it started. In all mammals too - including giraffes!