Eh, similar answer, your basic body plan goes back really far in your genetic history and is a really early part of embryonic development. All of your relative

Eh, similar answer, your basic body plan goes back really far in your genetic history and is a really early part of embryonic development. All of your relatives going back to a common ancestor ~500Ma have two eyes. It’s a quick internet answer not an essay, the exact correct common ancestor / taxonomy group is a bit difficult to pin down. Bilateria is the reason the number is even… some common ancestor after you split with spiders is the “exactly two” reason, which i think is all vertebrates now, or at least close to that level.