Evolution

Following up his cosmic Manifold series, Stephen Baxter peers back on a more prosaic history in the worthy yet uneven Evolution. The book is nothing less than a novelization of human evolution, a mega-Michener treatment of 65 million years starring a host of smart, furry primates representing Homo sapiens's ancestry. Each stage of our ancestry is represented by a character of progressively increasing intelligence, empathy, and brain size, who must survive predation and other perils long enough to keep the natural-selection ball rolling. While Baxter carefully follows some widely accepted theories of evolution--punctuated equilibrium, for instance--he also strays from the known in postulating air whales and sentient, tool-wielding dinosaurs. And why not? There's nothing in the fossil record to contradict his musings about those things, or about the first instances of mammalian altruism and deception, which he also lets us observe. From little Purga, a shrewlike mammal scurrying under the feet of ankylosaurs, all the way through Ultimate, the last human descendant, Baxter adds drama and a strong story arc to our past and future. But he spends too much time on details of the various prehumans' lives, which can become repetitive: fight, mate, die, ad infinitum. And readers eager for a science-fictional adventure will only find satisfaction in the posthuman chapters at the end. Despite these flaws, Evolution grips the attention with an epoch-spanning tale of the random changes that rule our genetic heritage. Recommended. --Therese Littleton