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(EYE) The iconoclastic Swiss developmental biologist Walter Gehring, at the University of Basel, has promulgated this revision most forcefully. One of the discoveries of the hox genes (responsible for laying out body plan),Gehring went on to make second monumental discovery in 1995, in one of the most startling experiments in biology. Gehring's team took a gene from a mouse and inserted it into the fruit fly Drosophila. This was no ordinary gene, with a minor ensemble role: under its malign guidance the fruit fly suddenly started sprouting whole eyes on its legs, wings and even antennae. These strange diminutive eyes peeping out from peculiar places were not the familiar camera eyes of mice and men, but compound eyes, displaying all the arrays of facets characteristic of insects and crustaceans. What this gruesome experiment proved with a visceral force was that the genes needed for growing an eye in a mouse and a fly were the same: they had been preserved, with amazing fidelity, down 600 million years of evolution, ever since the last common ancestor of vertebrates and invertebrates, to the point that they were still interchangeable. Put the mouse gene in a fly and it took over the fly systems, wherever it was place, commanding the subordinate hierarchy of fly genes to build an eye right there on the spot. ~ Page 195