I'd get that we evolved one perfectly formed eye, but how did the other one evolve exactly the same, same for legs, arms and fingers and toes.

what im asking is how did chance mutations happen twice isn't that a bit too lucky?

i know this sounds like a ID type of question, it really isn't I'm just generally stumped how nature could do this by blind luck?


Hi Laura,

The concept of biological symmetry is an old one. It has been estimated that this trait developed in organisms as long as 500 million years ago. Thus, the biological symmetry has been around for so long that something like the human eye (which is far from perfectly formed by the way!) has always been in development as a symmetrical pair and not one and then the other.

Remember that nothing in evolution is really about luck. There is a well honed selection process. Biological symmetry has become sop widespread amongst various organisms as those species which evolved this characteristic were more successful that their conuterparts which did not.

Here is a well put together video that might help clarify why this selection is beneficial: https://www.youtube.com/watch?v=L6SYhQNQtJg