[eli5] Why do insects have lots of legs while larger animals have 4 or 2? Also, why aren’t there any animals (that I know of) with 3 legs?

Question

[eli5] Why do insects have lots of legs while larger animals have 4 or 2? Also, why aren’t there any animals (that I know of) with 3 legs?

In: 381

Answer 1

Technically, whales and dolphins have 3 legs. But they started as four-legged animals and their 2 back legs fused together for swimming.