There are few science paradigms that survive and continue their influence for very long—most disappear within a decade. So it was a remarkable gathering at the Beckman Center of the National Academies of Science and Engineering in Irvine, California (hosted by John C. Avise and Francisco J. Ayala), where a group of eclectic evolution experts—biologists, philosophers, thinkers, historians, and empiricists—met to reflect upon 150 years of influence exerted by On the Origin of Species and the 200th birthday of its author, Charles Darwin. In 17 brilliant and colorful lectures, we heard updates, details, and advancements centered on nature’s examples of natural selection and two carryover concepts that intrigued Mr. Darwin: artificial and sexual selection. The historians and philosophers revealed timeless insights into the prescience of Darwin’s logic and dismissed as rubbish conspiracy theories that imply he purloined ideas from Alfred Russel Wallace. Francisco Ayala marveled at Darwin’s propensity to erect hypotheses over any biological observation and then to begin the scientific process of falsification (or validation) a century before granting bodies began to instruct us to follow this format in our research proposals. Elliott Sober reminded us that adaptive characters offer evidence of their cause, natural selection, while nonadaptive or even maladaptive characters are better for imputing common ancestry. Adaptation happens frequently, leading to parallel, independent origins of flight and of aquatic and terrestrial locomotion, but neutral traits form the currency for modern coalescent and phylogenetic reconstructions. Darwin’s rough sketch of a bifurcating tree of life connecting related species was shown often to remind us that temporal transition of species is a continuous branching process that continues today.
With but 17 talks, the speakers’ examples proved but a snippet of the possible richness of study and empiricism that the Origin has since spawned; indeed, a score of Darwin’s birthday celebration symposia scheduled this year across the globe testify not only to the expansiveness of evolutionary theory and practice to all corners of biology but also to its critical role as a bedrock in modern biology, from medicine to agriculture to natural history and ecology. Rich, natural illustrations of sexual selection in beetles and small terrestrial, aquatic, and marine critters affirmed the notion that there are countless discoverable strategies for how to proliferate and survive in our world. Darwin perceived artificial selection of domesticated animals and plants by human agency as providing a cogent natural laboratory example of how selection can change things. And change things it did: When Neolithic farmers in the Near East set up the first villages and communities, domestic species were chosen and selected almost simultaneously. Some believe this event changed the world enormously, providing a ready food supply, clothing, servile labor, sport, transport, and even home companions. Charles Darwin saw domestication as a validation of the force of natural selection, while others see it as the lever by which civilization overtook the globe in so short an interval.
Pause to consider the influence of evolutionary theory and practice, the Darwinian Revolution, as Michel Ruse termed it, made us remember how much it really changed science. Darwin’s genius was not only deductive and empirical; he was also a master communicator, the Abraham Lincoln of his day. His ideas were understood clearly and embraced widely despite the cacophony of theist protestations. His image appears on the 20-pound English note; his legacy is celebrated in a three-story marble mural of his notebook in Beijing; and academic departments of evolutionary theory and practice flourish in the world’s universities to inform us of the intricacies of the process in the era of DNA sequencing and genomics. I wish I could have known Mr. Darwin, but instead, perhaps I should simply try to attend all the celebrations of his theory and influence now, so many years since his birth.
About the author
Stephen J. O'Brien is chief of the Laboratory of Genomic Diversity at the National Cancer Institute in Frederick, Maryland. He spoke last week at the U.S. National Academy of Sciences Sackler colloquium on evolution, Two Centuries of Darwin, and came away with these thoughts.