They are correct that punctuated equilibria apply to sexually reproducing organisms and that morphological evolutionary change is regarded as largely (if not exclusively) correlated with speciation events. However, they err in suggesting that we attribute stasis strictly to "developmental constraints," which represent only one of a set of possible mechanisms that we have suggested for the causes of stasis. Others include habitat tracking and the internal structure of species themselves [for example, (2)].
An insider's provocative account of one of the most contentious debates in science today When Niles Eldredge and Stephen Jay Gould, two of the world's leading evolutionary theorists, proposed a bold new theory of evolution—the theory of "punctuated equilibria"—they stood the standard interpretation of Darwin on its head. They also ignited a furious debate about the true nature of evolution. On the one side are the geneticists. They contend that evolution proceeds slowly but surely, driven by competition among organisms to (...) transmit their genes from generation to generation. On the other are the paleontologists, like Eldredge and Gould, who show in the fossil record that in fact evolution proceeds only sporadically. Long periods of no change—equilibria—are "punctuated" by episodes of rapid evolutionary activity. According to the paleontologists, this pattern shows that evolution is driven far more by environmental forces than by genetic competition. How can the prevailing views on evolution be so different? In Reinventing Darwin, Niles Eldredge offers a spirited account of the dispute and an impressive case for the paleontologists' side of the story. With the mastery that only a leading contributor to the debate can provide, he charts the course of theory from Darwin's day to the present and explores the fundamental mysteries and crucial questions that underlie the current quarrels. Is evolution fired by a gentle and persistent motor and fueled by the survival instincts of "selfish genes"? Or does it proceed in fits and starts, as the fossil record seems to show? What is the role of environmental changes such as habitat destruction and of cataclysmic events like meteor impacts? Are most species inherently stable, changing only very little until they succumb to extinction? Or are species highly adaptable, changing all the time? Eldredge sorts through the major findings and interpretations and presents a lively introduction to the leading edge of evolutionary theory today. Reinventing Darwin offers a rare insider's view of the sometimes contentious, but always stimulating work of scientific inquiry. PRAISE FOR NILES ELDREDGE'S PREVIOUS BOOKS The Miner's Canary: Unraveling the Mysteries of Extinction "The Miner's Canary rings with integrity. The author takes care to present opposing views. Some readers, indeed, might view Mr. Eldredge as a little too self-effacing; he is, after all, one of the world's leading experts in his field."—The New York Times Book Review Fossils: The Evolution and Extinction of Species "... an important and informative book. It is also delightfully idiosyncratic. This is no scholarly treatise defending academic argument. It is an essay for everyone interested in the story of earthly life."—The Christian Science Monitor Life Pulse: Episodes from the Story of the Fossil Record "This is Earth history on a grand scale; those who enjoy the works of Stephen Jay Gould will appreciate Life Pulse."—Publishers Weekly. (shrink)
This is a first-hand account of the discussions going on between biologists of different persuasions. On the one hand are the ultradarwinians, who emphasize the supremacy of the gene and natural selection, and on the other, the naturalists, who focus on whole creatures, rather than on genes.
We propose that the onset and progressive destructive action of cancer within an individual bears a profound and striking similarity to the onset and progressive human-engendered destruction of global ecosystems and the extinction of entire species. Cancer in the human body and our human role in planetary, especially biotic, degradation are uncannily similar systems. For starters, they are the only two known complex systems where a discrete component changes its normal ecological role and function—turning on and potentially killing its host, (...) and in so doing, itself. Both are “hostile takeovers.” Clearly, humans are integral to both systems. With cancer we are the host and victims of the rogue behavior of what starts out as a normal, healthy, and functionally important part of our bodies. With the biodiversity crisis, we are the part of the system that has changed, expanded, and proven so destructive to the system in which we live. We argue that given that these threats to our bodies and Earth are both essentially ecological diseases, understanding the critical role of ecological interdependencies for avoiding both cancer’s and humankind’s destruction of their respective homes should hopefully promote better stewardship of both by the only animal capable of recognizing the problems—us. (shrink)
Published comments by American scientists on Darwin’s evolutionary theory are rather rare in the latter half of the 19th century. Clarence King, the founding director of the U.S. Geological Survey in 1879, and an experienced field geologist, focused on the relation between Darwin’s evolutionary concepts and the larger context of Hutton/Lyell’s uniformitarianism versus Cuvier’s catastrophism in his 1877 paper, “Catastrophism and Evolution.” King knew that the fossil record contains little or no data supporting Darwin’s vision of gradual evolutionary change. Instead, (...) using horse evolution seen in the rocks of the American West, the very example that by the 1920s had become the shining exemplar of gradual evolutionary change, King argued for catastrophic extinction and evolutionary replacement by “plastic” species that were able to survive in modified form as components of the succeeding biota. Though he could not see such change as involving natural selection, in this novel use of the term “plasticity,” there may well be adumbrations of modern evolutionary biology. King’s themes became muted as Americans began to embrace more fully Darwin’s work. But his version of catastrophism never entirely disappeared, especially in paleobiological circles. And it came back in more fully modern form with force beginning with the work of Norman D. Newell on mass extinctions in the mid-20th century—and with that of two of his students: Eldredge and Gould’s “Punctuated Equilibria.” This essay introduces King’s “Catastrophism and Evolution” for the journal’s “Classics in Biological Theory” collection; King’s article is available as supplementary material in the online version of this introduction. (shrink)
In the Modern Synthesis, the ontology of species is context-dependent: species are seen as "individuals" at any instant in geological time; through time, species-lineages are class-like entities regularly transforming themselves into other, descendant species. Moreover, at any one instant in time, species are predominantly construed as reproductive communities; through time, they are seen as economic entities, bound together by the joint possession of anatomical similarities among constituent organisms. It is argued that a more complete picture sees species as spatiotemporally bounded (...) historical "individuals", hence as reproductive communities in time as well as space; that species are not economic units; and that a complete evolutionary theory must address large-scale economic units as well as large-scale informational units, visualizing particular instances of such hierarchically arranged classes as spatiotemporally bounded historical entities -- i.e., as "individuals". (shrink)
Grene's Two Evolutionary Theories (1958), a philosophical analysis of the nature of scientific disputes, itself contributed directly to discourse in evolutionary theory. I conclude that Grene's descriptions of two rival theories of evolutionary paleontologists — those of George Gaylord Simpson, who stressed traditional Darwinian continuity, and of Otto Schindewolf, who stressed discontinuity in paleontological data — were entirely accurate. But I further argue that both Simpson, as well as Mayr and Dobzhansky, had incorporated notions of discontinuity into their earlier work, (...) but later removed, or at least de-emphasized discontinuity, in their later work. Grene's analysis, published in the year of the Darwinian centennial, was initially treated as a provocative sore point. The paper kept the issue of discontinuity alive in evolutionary theory, and directly influenced work in the 1960s and 1970s, which restored and further elaborated on the significance of discontinuity in evolutionary theory. (shrink)