Life at the edge

The pull of the sea has influenced the course of vertebrate evolution
hugely. In At the Water’s Edge: Macroevolution and the Transformation of Life,
Carl Zimmer, an award winning science writer and editor for the American
magazine Discover, tracks the story expertly from the first aquatic tetrapods,
around 360 million years ago, to the mammals that have given up the struggle on
land and returned to the water. Published by Free Press, £14.68, ISBN
0684834901.