Gould, Stephen Jay

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Gould, Stephen Jay 1941-2002

Stephen Jay Gould was a paleontologist, evolutionary biologist, essayist, and public intellectual. He lived a rich life achieving heights of academic success as a professor at Harvard University as well as attaining public recognition as an erudite, literate scientific essayist. Gould’s importance stems from his distinctive and important contributions as an evolutionary biologist and paleontologist, as well as his participation in public debates bringing his humanist and scientific commitments to bear on important social and scientific issues.

As a biologist Gould is best known for the theory of “punctuated equilibria” which he formulated jointly with the American paleontologist Niles Eldredge. The fossil record is an imprint of the past providing researchers with extensive evidence not only for the fact of evolution but a detailed map of the branching pathways connecting the diversity of life. The evolutionary paths emanating from different life forms can be traced through the chronological ordering of this fossil record. In standard Darwinian explanation the pace of evolutionary change is assumed to be slow. Accordingly, small incremental changes are accumulated to amount eventually to the grand differences that scientists associate with distinct species. The fossil record, however, does not show continuous change between life forms; rather there seem to be gaps. These discontinuities in the record could reflect scientists’ incomplete knowledge or simply gaps in the fossil record itself. Gould and Eldredge attempted to explain the “gaps” in the fossil record by questioning the assumptions made about the pace of evolutionary change. They argued that for long periods species enjoy stability, giving way to rapid and drastic change over short periods of time. Thus, the so-called gaps in the fossil record actually reflect a fact about the pace of evolutionary change rather than representing missing evidence.

Gould viewed evolutionary biology as a historical science. To him evolution was not a deterministic unfolding of events but a process highly contingent on the vicissitudes of circumstance. His views brought him into conflict with some of his peers who tried to veer evolutionary biology toward a more mechanical paradigm in which the evolutionary process was reduced to natural selection operating at the genetic level. Perhaps his most visible sparring partner in this debate was Richard Dawkins, who had presented arguably the strongest version of the mechanical paradigm. Dawkins envisioned organisms as “lumbering robots” carrying out instructions encoded in the organism’s DNA. Dawkins departed from orthodox Darwinism in placing the gene as opposed to the organism as the unit of selection. Gould’s opposition to this view found expression in a number of interesting ways.

First, he argued that natural selection, while an important and perhaps even dominant motor of evolution, was not the only driving force. He derided the pans-electionism of his opponents as a “panglossian paradigm” in which every feature of the organism was furnished with an adaptationist “Just So” story—a reference to Rudyard Kipling’s humorous children’s stories, particularly the ones about the origin of features of animals. Gould considered a multiplicity of mechanisms as important in evolution. These mechanisms included random reproductive success of some features due to the dynamics of finite populations, as well as structurally inevitable correlates of selected features where these correlates provide no reproductive advantage.

Second, Gould opposed reduction of evolution to the level of genes. He accepted as a fact that genes are responsible for the heritability of traits, but argued that selection occurs at the level of the organism per the Darwinian paradigm. Evolution to Gould could not be understood unless one allowed for different hierarchical levels of study; this hierarchy included the genetic level, the organism, and the species—each one important for a different set of evolutionary questions.

Third, Gould argued that the reduction of the organism to its genotype led ineluctably to a whole set of mistaken ideas which he collectively termed biological determinism. Biological determinism, as expressed in the ideas of sociobiology and evolutionary psychology, is the belief that complex behavior of organisms can be understood as following from the organism’s genetic make up, and are thus permanent features of the organism. As an example, a determinist might argue that a person’s genes determine her or his level of intelligence.

Gould went on to understand the questions that biological determinists tried to answer as historically conditioned. He saw in the determinist program a program that justified the stratification of our present-day society along gender, racial, and economic lines by providing these social realities a biological justification.

Gould’s scientific interests intersected significantly with his social commitments. He participated in public debates arguing against creationism and the genetic basis for behavioral differences between racial, gender, and class groupings. He wrote prolifically for the lay public on science, history, and society and achieved a considerable amount of fame and influence as a writer of popular science.

SEE ALSO Darwin, Charles; Punctuated Equilibrium