Stereoscopic vision or two eyes?
It seems that something as intricate as stereoscopic vision would have have came along a little further down the evolutionary line so to speak - there are still lots of organisms that don’t have it. So it seem mighty handy that we had two eyes in case that came up. So why have two eyes if you don’t yet have stereoscopic vision? Sure, two are better than one (in case you loose one) but then why wouldn’t 3 be even better? I remember from the blind cave fish thread (sorry no link) that eyes are so “expensive” to have that they are selected against relatively quickly when not needed. So it seems early life forms would have been better off with just one receptor patch.Wiki tells us:
Did ‘we’ need two of those (were there two of those)? None of this is my field of study so I could be way off on anything I’ve said here, but it seems odd to me that the two eye model developed before the ability to have stereoscopic vision was a possibility.