Pattern of Evolution Clothbound

In these rich, dense, stimulating essays, Eldredge (Life in the Balance), curator of invertebrate paleontology at the American Museum of Natural History, improvises on Darwin by sketching a grand, sweeping, ecologically based theory that links biological evolution to physical events in the earth's history. He maintains that the driving force of evolution is global mass extinctions of a majority of species, which paves the way for the advent of new species that inhabit and rebuild disrupted ecosystems. What caused these extinctions? Eldredge goes beyond the usual culprits--rapid global cooling, periodic ice ages, catastrophic meteor collisions--by also citing plate tectonics, shifts in the earth's crust causing dramatic changes in oceanic circulation and global climate. In a sense, his theory fleshes out the notion of ""punctuated equilibria"" he developed with Harvard biologist Stephen Jay Gould, which holds that evolution proceeds episodically, in relatively short spasms that ""punctuate"" monotonous eons where nothing much happens. Mixing scientific adventure (the author's search for the Taita falcon, one of the world's rarest birds, near Victoria Falls in Zimbabwe) and freewheeling speculations on geology, paleontology, genetics and evolutionary theory, these elegant essays explore how the recognition of patterns in nature--by Darwin, Linnaeus, geologist James Hutton, continental-drift pioneer Alfred Wegener and others--often provides the key to scientific breakthroughs. A deep probe of how scientific advances emerge, the book touches upon current controversies as well, including the ""snowball earth"" theory of CIT geologist Joseph Kirschvink, which asserts that massive glaciers invaded the tropics just 600 million years ago, and that the earth's crust and upper mantle rotated as a shell 90 degrees, stirring the evolutionary pot. Author tour; rights: the Spieler Agency. (Nov.)