The expectations of theory colour perception to such a degree that new notions seldom arise from facts collected under the influence of old pictures of the world. New pictures cast their influence before facts can be seen in a different perspective.

One measure of the greatness of a work is that the characters who play roles in the narrative feel its essential truth. As someone who is proud to have been there during much of the action David Sepkoski describes, I give his description and analysis of the history of paleobiology a five-star rating; to my mind, this actually was the way it was.

If it is true that an influx of doubt and uncertainty actually marks periods of healthy growth in a science, then evolutionary biology is flourishing today as it seldom has flourished in the past. For biologists collectively are less agreed upon the details of evolutionary mechanics than they were a scant decade ago. Superficially, it seems as if we know less about evolution than we did in 1959, the centennial year of Darwin's on the Origin of Species.

Paleontologists ever since Darwin have been searching (largely in vain) for the sequences of insensibly graded series of fossils that would stand as examples of the sort of wholesale transformation of species that Darwin envisioned as the natural product of the evolutionary process. Few saw any reason to demur - though it is a startling fact that ...most species remain recognizably themselves, virtually unchanged throughout their occurrence in geological sediments of various ages.

The expectations of theory colour perception to such a degree that new notions seldom arise from facts collected under the influence of old pictures of the world. New pictures cast their influence before facts can be seen in a different perspective.

Darwin's prediction of rampant, albeit gradual, change affecting all lineages through time is refuted. The record is there, and the record speaks for tremendous anatomical conservatism. Change in the manner Darwin expected is just not found in the fossil record.

Paleontologist Niles Eldredge, a prominent evolutionist, said: 'The doubt that has infiltrated the previous, smugly confident certitude of evolutionary biology’s last twenty years has inflamed passions.' He spoke of the 'lack of total agreement even within the warring camps,' and added, 'things really are in an uproar these days . . . Sometimes it seems as though there are as many variations on each [evolutionary] theme as there are individual biologists.'