Cambrian Explosion - First eye fossils - 530-540 million years ago
Seemingly rapid appearance of most major groups of complex animals, diversification
Before 580 million years ago most organisms were simple
Charles Darwin saw it as an argument against evolution by natural selection
Geologist: Buckland (1784, 1856)
life is 3.5 billion years old. Australian rocks at warrawoona
Snowball earth theory
Eye evolution - Parker
Armour, defence in response to predator eyes
Burgess shale
arms race - rapid evolution
light sensitivity -> navigation by vision
96% of living species have eyesight that can discriminate the direction of light to within a few degrees
Jellyfish have eyes but no vision system
Dramatic advantage from having eyes
Eyes developed by species in water
Visible light is the one of only two wavelength ranges that can travel through water
Human eye is backwards and upside down
Irreducably complex? Intelligent design?
Punctuated Equilibrium - Eldridge and Gould - Evolution - long periods of near stasis followed by rapid movement