Student books : Spineless

The question of the origin and early evolution of the vertebrates is very
much on the agenda again. Before the Backbone by Henry Gee (Chapman & Hall,
£35, ISBN 0 412 48300 9) provides an excellent review of the main
contenders and themes in the debate. No clear winners yet: the arthropods,
echinoderms and hemichordates are still in with a chance of being our
ancestors.