Skepticblog

Two weekends ago, the country was absorbed in remembering the events of September 11, 2001, but September 10 was another anniversary:  the 70th birthday of Stephen Jay Gould, paleontologist, evolutionary biologist, historian of science, Harvard professor, prolific writer and columnist, and probably one of the most influential public scientists of the 20th century. A number of prominent evolutionary biologists and bloggers paid tribute to him, including P.Z. Myers, Jerry Coyne, and others. Even though Steve lived to the age of 60 and passed away on May 20, 2002, most of us were shocked when he was stricken so suddenly by cancer and wasted away to nothing in a matter of weeks. In spite of his rapid decline in health, during his final semester he gamely kept traveling up from his New York apartment to Harvard to teach his classes, even though he was so weak he could barely stand. Though he accomplished more in  his lifetime than any other scientist of his generation (books,  essays, research, scientific papers, etc.), most of us felt that his death at 60 was premature and that he had so much more to offer us had he lived his fullness of years.

Yours truly (right) with Gould (left) and Michael Shermer (center) at Mount Wilson Observatory, 2001.

I should explain to the reader of my personal perspective in this matter. Although I was never formally his student, Stephen Jay Gould was a friend and mentor to me while I was at Columbia University and the American Museum of Natural History (AMNH) as a graduate student from 1976-1982. When I arrived at the Columbia/AMNH program, all the grad students heard the legends of Steve when he was a grad student in the same program two generations earlier. Each year, the stories got more and more amazing: how he outshone all the other students with his brilliance, published his first paper early in grad school, wrote entire papers in a few hours of work, wrote his entire dissertation in a few hours/days/weeks when his advisor Dr. Norman Newell thought he should finish and defend, and so on. His were enormous shoes to fill, and we all felt his shadow when we were being evaluated as students. I saw him on numerous occasions when I was a grad student, not only at professional meetings, but also when he came down to Lamont-Doherty Geological Observatory to see for himself the work that Dave Lazarus and I (Lazarus et al. 1982) were doing on gradual evolution in plankton (he was more open-minded that you would expect), or when fellow student Paul Sereno and I paid a visit to him at Harvard while we were working on a project on allometry and dwarfing in mammals (Prothero and Sereno 1982). Subsequently, he was extremely supportive to me during my professional career, recommending me for a Guggenheim Fellowship (which I got, thanks to  him), plugging my work in his Natural History columns several times, and graciously replying to my letters whenever I had an idea that truly required his attention. When my job and my department at Knox College were about to be eliminated in 1983-1984, he spoke out not only in front of the audience at the GSA meeting, but also wrote letters on our behalf to try to reverse the decision. Thus, I cannot claim to be impartial about Steve, but I do speak from personal experience and from watching paleontology change over the past 40 years.

In many ways, Gould’s brilliance and success made him a target for fools and creationists, and turned him from merely a paleontologist into a media celebrity on par with Carl Sagan and Steven Hawking. Like Hollywood celebrities and other high-profile figures, Gould did not have as much privacy as he would have liked, dealt with the constant distraction of people demanding his time and attention, and everything he said or did was scrutinized. Shermer (2002) analyzes some of the criticisms of Stephen Jay Gould, and dissects his prodigious volume of writing about his favorite topics, and even the elements of his writing style. Much of the criticism stems from scientific jealousy and the complaint that Gould’s writing was too popular (the so-called “Sagan Effect”).  As Raup (1986) noted, Carl Sagan was denied many honors (such as election to the National Academy of Sciences) in his field and dismissed as just a popularizer of science, rather than as a research scientist. However, Shermer showed that Sagan continued to publish peer-reviewed articles at the same pace, even as he worked on “Cosmos” and wrote trade books. By contrast, Gould actually published more peer-reviewed science than he did books or essays for the general public. Gould’s productivity in every category (peer-reviewed articles, books, popular essays, book reviews, and the like) outstrips all the big-name scientists of his era, including Carl Sagan, Ernst Mayr, E.O. Wilson, and Jared Diamond. Gould was elected to the National Academy of Sciences, and became one of the most respected scientists in America.  He served as president of the American Association for the Advancement of Science (AAAS), the Paleontological Society, and the Society for the Study of Evolution (SSE). Gould received dozens of honorary degrees, and won nearly every award he was eligible for, including the MacArthur Fellowship, the so-called “genius award.” As a true measure of his fame across the culture, Gould was portrayed by a cartoon of himself (providing his own voice) on The Simpsons. Another episode of the same show that aired the week he died was dedicated to his memory.

Ironically, now people complain that the problem with science literacy in this country is that there are too few popularizers, and too few scientists who step out of their ivory towers to convey the importance of science for the general public. These critics include marine biologist Randy Olson, who made a documentary about creationism and scientific arrogance entitled “Flock of Dodos”, or Chris Mooney and Sheril Kirshenbaum, authors of Unscientific America: How Scientific Illiteracy Threatens our Future. It seems you can’t win. You can become a Carl Sagan or Stephen Jay Gould and have your professional peers snipe at you out of jealousy for your popularity, or you can retreat to your lab and let the culture critics complain that scientists are too aloof.

But the area where Gould is best known and most controversial is his lifelong quest to expand evolutionary biology, and bring paleontology to the “High Table” of evolutionary biology. As Gould (1983) himself pointed out, paleontology was virtually irrelevant to evolutionary theory from Darwin’s time until the 1940s. During the start of the Neo-Darwinian synthesis in the 1930s and 1940s, Gould (1983) argued that paleontology became subservient to evolutionary genetics, especially due to the work of paleontologist George Gaylord Simpson and his book Tempo and Mode in Evolution (1944). Although that book debunked a lot of false notions of earlier paleontologists, it also reduced all of the fossil record to just examples of gradual change and simple natural selection as preached by the Neo-Darwinists. When the Society for the Study of Evolution was founded in 1947 (with Simpson as first president), paleontological papers were published alongside those of geneticists in their flagship journal, Evolution.

By the time Gould’s generation of paleontologists came of age in the 1960s, paleontology was truly subservient to genetics. Few paleontology papers were published in Evolution any more. Both Gould and Niles Eldredge remarked that they came to the Columbia/AMNH program to study with Norman Newell and document evolutionary patterns in the fossil record, and found to their surprise that the expected pattern of gradual evolution was extremely unusual. As they detail in their books (Gould 2002; Eldredge 1995), the famous 1972 “punctuated equilibrium” paper was accidentally assigned to them by editor Tom Schopf, who wanted a review of speciation theory, not an area that Gould had worked on at that point. The “punctuated equilibrium” paper led to the realization that paleontologists who had long been trying to document gradualism had not kept up with implications of the allopatric speciation model developed 30 years earlier by Ernst Mayr and others during the Neo-Darwinian synthesis.

Once “punctuated equilibrium” became a hot topic, it dominated the journals and scientific debates. I vividly remember sessions at each professional meeting during the 1970s as knock-down drag-out fights between the old-guard gradualists and the “Young Turks” led by Gould, Eldredge, and Steve Stanley. Gould and Eldredge (1977) effectively answered most of the early criticisms of the “punctuated equilibria.” By the mid-1980s, a consensus had emerged from the paleontological community that nearly all metazoans (vertebrate and invertebrate, marine and terrestrial) show stasis and punctuated speciation through millions of years of geologic time and strata, with only minor possible examples of gradual anagenetic change in size (Geary 2009; Princehouse 2009; Hallam 2009). That has been the accepted view of paleontologists for better than 20 years now.

Yet you would never know this by looking at the popular accounts of the debate written by outsiders, who still think it is a controversial and unsettled question. Even more surprising is the lack of response, or complete misinterpretation of its implications, by evolutionary biologists. Since the famous battle at the 1980 Macroevolution Conference in Chicago, neontologists have persisted in misunderstanding the fundamental reasons why paleontologists regard punctuated equilibrium as important. Many have claimed that people like Simpson (1944) or other were thinking along the same lines, or that gradual change on the neontological time scale would look punctuated on a geologic time scale. They miss the point of the most important insight to emerge from the debate: the prevalence of stasis. Before 1972, paleontologists did overemphasize examples of gradual evolution, and they expected organisms to gradually change through geologic time, as they do on neontological time scales. But the overwhelming  conclusion of the data collected since 1972 shows is that gradual, slow, adaptive change to environments rarely occurs in the fossil record. The prevalence of stasis is still, in my mind, the biggest conundrum that paleontology has posed for evolutionary biology, especially when we can document whole faunas (Prothero and Heaton 1996; Prothero 1999; Prothero et al. 2009) that show absolutely no change despite major changes in their environments. That fact alone rules out the “stabilizing selection” cop-out, and for years now paleontologists and neontologists alike have struggled to find (unsuccessfully, in my opinion) for a good explanation for why virtually all organisms are static over millions of years despite huge differences in their adaptive regime.  The gradual adaptation of fruit flies and Galapagos finches may be good examples of short-term microevolutionary change, but they simply do not address what the fossil record has shown for over a century. This only became apparent when Gould, Eldredge, Stanley and others began to talk about species sorting, decoupling microevolution from macroevolution, and the importance of hierarchical thinking in evolutionary biology. Many neontologists appear to have a relentlessly reductionist attitude and simply “don’t get it,” no matter how many times and how clearly it has been explained to them.

Thus, almost 40 years since the original 1972 paper, we have a different kind of “two cultures” phenomenon of people with different mindsets talking past one another. Paleontologists have agreed for decades now that the prevailing message of the fossil record is stasis despite big changes in the environment. Based on the literature (Sepkoski and Ruse 2009), we have undergone a “paleontological revolution” with a less subservient approach to evolutionary biology. Most paleontologists are in agreement with Gould’s cry for the importance of species as entities, species sorting, and the hierarchical approach to macroevolution.  As Gould and Eldredge wrote in 1977, “why be a paleontologist if we are condemned only to verify what students of living organisms can propose directly?” Although Gould was the loudest voice for paleontology’s claim to an important role at the evolutionary High Table, any review of the books, papers, and presentations that paleontologists are releasing shows a non-neo-Darwinian, more pluralistic approach to evolutionary theory, especially when it comes to concepts like evolutionary paleoecology, mass extinction theory, and coordinated stasis.

Yet I look at what neontologists write about the topic, and it seems as if they simply cannot grasp what paleontologists have said over and over again. When I (Prothero 2003) wrote a review of two recent evolutionary biology textbooks, it was apparent that the authors had no clue about the implications of punctuated equilibria, species sorting, and the stability of species despite environmental changes. Instead, their approach to the topic revealed a profound misunderstanding of the important points, distortions of what is being claimed and what is not, and pointless critiques of old outdated arguments and trivial side issues, as if they were still reading the debate as it stood in the 1970s. Now and then you find concessions, such as Mayr (1992, 2001) admitting that the prevalence of stasis is a puzzle that has no simple answer, but by and large the neontological community still “doesn’t get it.” Paleontologists have been trying to communicate their distinctive perspective for a generation, culminating with Gould’s (2002) magnum opus, published just as he was dying. Yet the harsh reviews of Gould (2002) by neontologists showed that they still didn’t understand the critical issues and were rehashing issues that had been resolved by paleontologists 30 years ago. The journal Evolution still publishes almost no contributions by paleontologists, and the meetings of the SSE I have attended just reinforced how large the culture gap had grown. If these bellwethers are representative of the relationship between paleontologists and neontologists, then it seems clear that paleontology has still not claimed its rightful seat at the “High Table”.

I’m not sure why this is so. It could be the huge conceptual and culture gap between paleontologists and neontologists, and how the differences in timescale shape their thinking. It could be an artifact of academic Balkanization, where paleontologists are still largely in geology departments and rarely encountered by evolutionary biologists. It could be professional territoriality and turf wars. If Gould (1980, 2002) was right and the best way to understand macroevolution comes from the fossil record, then a lot of fruit fly research is irrelevant. Even Simpson (1944) made this point: “Experimental biology . . . may reveal what happens to a hundreds rats in the course of ten years under fixed and simple conditions, but not what happened to a billion rats in the course of ten million years under the fluctuating conditions of natural history. Obviously, the latter problem is more important.”

In May 1984, the evolutionary biologist John Maynard Smith wrote in Nature, “The palaeontologists have too long been missing from the high table. Welcome back.” But judging from the way in which paleontology is presented in biology textbooks, the lack of paleontology papers in Evolution, and the harsh response to Gould’s (2002) final work, I think this welcome was premature. Now that the most articulate spokesman for paleontology has been gone for nine years, I doubt that this will ever change.

Even 9 years after his death, we paleontologists still miss Steve. I  hear it all the time at paleontology meetings. Just like everyone can remember what they were doing and where they were when they first  heard about the 9/11 attacks, every paleontologist I know vividly remembers how and when they heard the news of Steve’s death. Paleontology may never have a spokesman with such a high public profile again. His influence is still in the culture, as shown by the fact that bloggers commemorated his 70th birthday last weekend, and that  his ideas are still being debated almost a decade after his death. Perhaps the ultimate tribute to him was “Project Steve” of the NCSE, where they tallied up scientists who accepted evolution whose names were Steven, Stephen, Stephan, Stephanie, or other cognates—and those names alone far outstrip the number of “scientists who question evolution” that the creationists are always touting. It is the ultimate send-up of these silly creationist efforts, and just the kind of clever idea against Gould’s old nemesis that he would appreciate most.

Happy Birthday, Steve!