Dawkins reporting from the Galapagos, Part II

Richard Dawkins’s second article in a series of three, from The Guardian:

DawkinsLast week, “The giant tortoise’s tale” described ancestral tortoises floating inadvertently across from South America, colonising the Galápagos Islands by mistake, subsequently evolving local differences on each island and giant size on all of them. But why assume that the coloniser was a land tortoise? Wouldn’t it be simpler to guess that marine turtles, already at home in the sea, hauled up on the island beaches as if to lay their eggs, enjoyed what they saw, stayed on dry land and evolved into tortoises? No. Nothing like that happened on the Galápagos islands, which have only been in existence a few million years.

More here.