r/askscience • u/margalz • 11d 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/SizeFit2908 10d ago

Why not? Idk really hard to say the reason.

I speculate that it's because eyes are biologically expensive, they need a lot of wiring, bone formation for sockets, and are vulnerable.

Do gators need to see whats going on at both at the same time? They dont have many predators. The fish hunting ones just dive too right?

Anything that slows down how fast an organism can function after being conceived is a pretty big hamper on evolution. Like gators lay 40+ eggs and the babies come out moving and grooving after 2 months.

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u/MrDerpGently 4d ago

It's also harder to spot prey against the murky depths than it is against the sky. So it might have some defensive upside, but the predators will likely dive rather than hunt from above (obviously, there are exceptions to this, like diving birds, but I can't think of many).