Throughout much of the animal and even plant kingdoms, almost the same ancient genes code for almost the same proteins. And further, to everyone's astonishment, the genes involved in making the complex eyes of fruitflies are close matches to those involved in making the very different eyes of octopuses and people. So what leads to the nature's 'endless forms most beautiful'? The key to this mystery is being unravelled by 'Evo Devo' or the new science of evolutionary development biology. By looking at how a single-celled egg gives rise to a complex, multi-billion celled animal, Evo Devo is illuminating exactly how new species - butterflies and zebras, trilobites and dinosaurs, apes and humans - are made and evolved. The key, it turns out, is all about location and timing ...