Eye, eye

Fascinating story on the BBC site today about the discovery of the oldest "eye" known to science. The Trilobite fossil found in Estonia contained the very well preserved remains of a pre-compound eye. Compound eyes are the type we now see in insects like bees and flies, they consist of a collection of rod-like cells that act as tiny eyes in their own right, the aggregation of signals from each of these cells forms the image in the brain of the insect. The eye found in this fossil is simpler than modern compound eyes, it lacked a lens and only has around 100 cells, perhaps a pre-cursor to later compound eyes found in Trilobites from a few million years later. The fossil dates to around 530 million years ago, an era when there was relatively rapid (in evolutionary terms) changes going on in the warm seas of the pre-continental Earth. Another "smack in the eye" (see what I did there) for our creationist brothers and sisters who insist that eye's are "far too complex" to evolve, well, here's a simple eye for us to feast on, only a 100 modified cells, in fact just one single light sensitive cell would quite probably provide a selective advantage (i.e. quite easy to explain in genetic-mutation terms).