In Search of Deep Time: Beyond the Fossil Record to a New History of Life

Deep Time, according to John McPhee, who coined the term, refers to the millions of years in the geologic record, as opposed to our everyday sense of time in which centuries and millennia seem endless. In this eloquent treatise, Gee, a senior science writer for Nature, asserts that the dramatically different scales on which deep and ordinary time are measured have significant implications for evolutionary biology and paleontology. He takes the provocative and perhaps extreme view that scientists will never be able to successfully answer evolutionary questions about the origins of species, or about the pressures leading to various adaptations, because events that occurred in deep time are not accessible to experimentation. Indeed, he argues, such questions should be considered outside the realm of science. In the place of traditional biology, Gee offers the field of cladistics, ""a way of looking at the world in terms of the pattern that evolution creates, rather than the process that creates the pattern."" By using statistical techniques to group anatomically similar organisms, both extant and extinct, cladists assert that they are able to demonstrate testable evolutionary relationships. While Gee does a superb job of explaining the basics of cladistics and of revealing its use in the controversies swirling around the origins of birds and of humans, more cautious thinkers may find that he exaggerates both its power as a tool and its acceptance by the scientific community. (Dec.)