Stephen Jay Gould, American paleontologist, dies. Stephen Jay Gould was one of the best known and most popular writers both on general science matters and, specifically, on his own field of evolutionary biology.
He wrote an unprecedented 300 consecutive monthly columns ("This View of Life") for Natural History magazine along with 20 best-selling books and nearly one thousand scientific papers.
From 1967 until his death he taught at Harvard University, eventually becoming Professor of Geology and Curator of Inverterbrate Paleontology, Museum of Comparative Zoology. Along with paleontologist Niles Eldredge, Stephen Jay Gould developed the concept of "punctuated equilibrium" to explain an oddity of the fossil record: apparent "bursts" of speciation in between long periods of little or no change.
According to Eldredge and Gould, environmental stresses would frequently be low enough that there would not be any reason for evolutionary changes. However, when dramatic environmental shifts occur, evolutionary change can and does happen quite rapidly (relatively speaking — even "rapid" changes take place over tens of thousands of years).
Although there are critics of punctuated equilibrium, among them Richard Dawkins, the real differences appear to be that of emphasis rather than substantive disagreement. That may in part be Gould's own fault — one of the complaints of opponents is that he created a straw man of classical Darwinian evolution in order to make his ideas appear newer and more radical. Gould, however, denied this and argued that sometimes the gradual shifts in focus can produce as much new insight in science as do the revolutionary changes.
Another important idea in evolution which Gould advocated and popularized was that the evolutionary process is one with no predetermined outcome. What this means is that if the entire process started over — if the "tape" were "rewound" and played again — we shouldn't expect to see the same results:
"Humans are not the end result of predictable evolutionary progress, but rather a fortuitous cosmic afterthought, a tiny little twig on the enormously arborescent bush of life, which if replanted from seed, would almost surely not grow this twig again."
Critics agree that humans, as we currently know them, may not be produced if we go back far enough in the evolutionary record. However, they also argue that some large-brained, intelligent species would probably still exist. It might not be from the line of primates and it might not even be a mammal, but it would still be here.