Professor Lars Schmitz joins WIRED to guide us through a giant tree of life mapping the evolution of eyes in the animal ...

But we know for certain that this back-to-the-water evolution ... these animals is necessarily a direct ancestor of the whales we know today; they may be side branches of the family tree.

Evolutionary trees show how different species have evolved ... So the question is, why? How could an animal be so precisely adapted to a particular lifestyle? The answer is natural selection.

All animal evolution for the last half billion years has come from tinkering with these Cambrian body plans. Then, between about 570 and 530 million years ago, another burst of diversification ...