[jjcon]

> there is simply not enough information in a 2D picture to get 3D distance information, even with parallax. Our eyes also can't solve this problem.

That is certainly false - perhaps with extremely limited amounts of parallax yes but that isn't how this setup is working. Humans certainly use heuristics not only because our brains are capable of it but also because a face only has a few mm of separation, with enough parallax you can get phenomenal 3d information out of a visual system. Replacing a single sensor here is certainly not too general for good performance but also my point again was never to say this was an optimal or perfect solution only to say evolutionary arguments are stupid here because we build machines and algorithms every day that operate better than evolution does.