BBC Bitesize talks you through the names you probably never knew for five parts of the body you see all ... something from of the corner of your eye. A shorter - but not necessarily snappier ...

In other words, what good is five percent of an eye ... gone through changes and complexities to form the human eye, with its many parts and astounding abilities. Through natural selection ...

Part of the charm ... or that there are five distinct types of compound eyes. Aside from specialist reviews, this is the best text-book treatment of eye evolution that I know of.

Follow me please class. We’re here at the optician’s to get a good look at a human eye and find out how it works. Human eyes are actually spheres. The part that we can see is only just the front.