In defense of paleontology

Fossil fish from the Eocene age Green River Formation in Colorado. From Wikipedia.

I am pretty tired of Richard Dawkins putting down paleontology. In his 2004 tome The Ancestor’s Tale, as well as in his latest book The Greatest Show on Earth, Dawkins felt compelled to cast the fossil record as an unnecessary bonus when it comes to demonstrating the reality of evolution. “The evidence for evolution would be entirely secure,” he asserts in the latter book, “even if not a single corpse had ever fossilized.” While this statement contains a crumb of truth – we have learned much about evolution by studying living organisms – I cannot help but feel it snobbishly denigrates an entire field which has greatly influenced our understanding of evolution. This trend is hardly new.

In his 1919 appraisal of evolutionary science, A Critique of the Theory of Evolution, the embryologist Thomas Hunt Morgan damned paleontology with faint praise. No discipline more immediately demonstrated the truth of evolution than paleontology, Morgan wrote, but when paleontologists made any attempt to move beyond simply describing fossils they had a bad habit of concocting hare-brained evolutionary schemes:

My good friend the paleontologist is in greater danger than he realizes, when he leaves descriptions and attempts explanation. He has no way to check up his speculations and it is notorious that the human mind without control has a bad habit of wandering.

While perhaps a bit harsh, Morgan’s criticism was not entirely without merit. Between the late 19th and early 20th centuries many paleontologists favored non-Darwinian evolutionary mechanisms, from ideas similar to those of Lamarck to the existence of internal driving forces which pushed animals towards particular end points (making extinct creatures failed experiments in a lineage’s attempt to reach that goal). Nevertheless, even after paleontologists like W.D. Matthew, G.G. Simpson, A.S. Romer, and others cast out these ideas in favor of natural selection and the “paleobiological revolution” of the late 20th century, paleontology is still often cast as a science that can do little more than offer up proof that evolution occurred but never say anything more about it. In this dim appraisal of the field paleontologists should be content to describe their old bones and avoid theorizing, as if to say “Thanks for those transitional fossils; now go find some more and stop bothering the grown-ups.”

This blinkered view ignores the importance of paleontology to the development of evolutionary thought. The similarity of fossils to living organisms inspired both Jean Baptiste Lamarck and Charles Darwin to begin considering how new species might be brought into existence over the course of time, and in an even more general sense the establishment of paleontology confirmed the existence of “lost worlds” filled with unfamiliar animals, all of which came into existence and were extinguished long before the emergence of our own species. Hence paleontology provided the background and historical context in which debates over evolution took place, and while it is true that Darwin could not present an array of minutely-graded transitional forms when he published On the Origin of Species in 1859, it is significant that he spent two entire chapters considering the implications of his theory for paleontology and vice versa.

That was over 150 years ago, of course, and despite the way it has been cast in several recent popular treatments of evolution, modern paleontology is about much more than providing fossilized confirmations of Darwin’s view of life. Perhaps more than ever, paleontology has become a synthetic discipline which has incorporated aspects of genetics, evo-devo, and other sciences to not only identify transitions in the fossil record, but explain how they occurred. Nor has paleontology just been a consumer of ideas developed in other disciplines. The recognition of mass extinctions, evolution in the mode of punctuated equilibrium, the roles of contingency and constraint in evolution, and other important ideas have all emerged out of, or at least have been given more prominence through, studies of the fossil record.

I cannot claim to be an unbiased observer in this matter. I am enthralled by paleontology, and I feel that it often does not receive the credit it deserves. (Hence at least part of my motivation for composing Written in Stone.) This is an exciting time for the field, one in which paleontology is expanding to generate cross-disciplinary studies between laboratory and field-based science, yet it is too often cast as the never-ending search for more fossils and little else. This is a shame, especially because academic positions for paleontologists are becoming increasingly rare. Be it due to state budget cuts or the perception that paleontology is not a worthwhile pursuit, many museums and departments all over the United States are being closed down, meaning that it is more difficult than ever for paleontologists to find a job. While perhaps not intended this way, the continuing implication that paleontology is unnecessary to evolutionary studies perpetuates the image that it is nothing more than the collection and curation of fossils, and I fear that this further spurs the closure of opportunities for paleontologists to do their work. This is the sad paradox of modern paleontology, and I hope that these conditions soon change for the better.