Dr. Ariew will be speaking as part of the Evolution and Social Sciences lecture series. See link below for more details.

**Why is the theory of natural selection so hard to understand?**

In 1959, at a symposium celebrating the 100th anniversary of the publication of the Origin of Species, the geneticist and Nobel Laureate H.J. Muller presented a lecture with the provocative title, “One Hundred Years Without Darwin are Enough”. In it he bemoaned the lack of understanding, even among contemporary Darwinians, about the theory of natural selection. Fifty years later, the biologist and theoretician Francisco Ayala, writes an essay entitled “One hundred fifty years without Darwin are enough!” The addition of the exclamation point expresses his frustration. Why does natural selection continue to be badly misunderstood? I propose two related answers, one is historical, the other conceptual. The historical answer is that too many associate natural selection with Darwin’s theory. That causes confusion. There are significant differences between Darwin’s theory and the versions biologists employ today. One of the major differences informs the conceptual confusion over the theory of evolutionary theory: the modern theory invokes (to a much greater degree than Darwin’s did) “variational” thinking. Variational thinking is difficult to understand without adopting mathematical and statistical models.