Sesquicentennial

On July 1, 1858, Charles Darwin co-presented his concept of evolution by way of natural selection to the Linnaeus Society in London. In so doing, he lent his already-considerable scientific prestige to a number of ideas that had fallen into disfavor with the leading lights of the field of biology.

I say "co-presented" because Darwin gave credit to an amateur biologist, Alfred Russell Wallace, who had sent to Darwin a paper proposing evolution by natural selection earlier that year. Darwin had been working on the idea ever since his service on the HMS Beagle in the early to mid 1830's. He'd wanted to present an unassailable thesis before publishing -- but Wallace, a lesser-known figure in the academic world, was going to publish anyway. So Darwin wanted to be first with the idea, but he'd waited around too long. The co-publishing solved a few problems, including Wallace's desire for credit (he had produced the idea and gathered evidence independently or Darwin) and prestige (Darwin was a well-known and acclaimed biologist already, and his name lent credibility to the concept) while avoiding messy and possibly litigious problems for Darwin, who had, after all, dithered for more than twenty years before going public with his idea.

You can read more about the intellectual history of the event here, especially Wallace's involvement, at the Beagle Project.

But it is useful to remember that Darwin and Wallace's new idea was not evolution, which had already earned very substantial acceptance in the scientific community to the near-exclusion of creationist conceptions of biology. Darwin's new thought, which would ultimately be published in his seminal book The Origin of Species, was that evolution happened because of natural selection as opposed to other mechanisms.

Lamarckian evolution had been the prevailing school of thought before then. Lamarckianism is the concept of acquired inheritable characteristics -- Lamarck proposed that an individual creature enhances certain portions of its body through use, and passes along those characteristics to its descendants. Thus, a primordial deer that repeatedly strained its neck to eat leaves from the tops of trees and bushes would give birth to deer with longer necks -- and over many generations, the deer would eventually become giraffes.

It's actually kind of a seductive idea, and even Darwin himself resorted to Lamarckian explanations when pressed to explain aspects of human evolution after publishing his second book on evolution, The Descent of Man. But over time, his original concept of natural selection as the primary vehicle for evolutionary change was established as the best available explanation for the diversity of species and the fossil record.

Interestingly, the controversy that sparked as a result of the publication of these ideas 150 years ago was not originally based on any objection to evolution generally, just on the idea that so cruel a method as natural selection -- one that inherently involves the use of things like starvation and violence -- created so noble a creature as man. Few people objected to the idea that "lesser" species until about fifty years ago and the popularization of Biblical literalism in American culture. The only objections were to the evolution of man from different kinds of creatures. (Perhaps that's because it's so obvious that, for instance, dogs and wolves are related.)

So raise your glasses to Alfred Russell Wallace and Charles Darwin today. Thanks to their idea, we understand how bacteria and viruses change over their very short generations, and been able to use that knowledge to create antibiotics and vaccines. Their idea laid the foundation for modern genetics, which has created food for billions of people and enabled us to understand and control hundreds of diseases. They set in motion an intellectual revolution of at least Copernican power, and which has been instrumental in understanding medicine, biology, and science. Chances are good that you (and I, and most people that you know) indirectly owe their very lives to the science set in motion 150 years ago today in London.

By the way, "sesquicentennial" is one of my favorite words. It's fun to say, unless you have a lisp you cannot overcome. It seems so unlikely that there should be a word to describe the 150th anniversary of something, and that it be such a delicious-sounding word at that, blending the sound if not the actual etymology of a tongue like Cherokee or Menomenee, with the Latin root "cent" makes it seem distinctly American to me. I first learned of the word as a child seeing it on a Texas license plate commemorating the sesquicentennial of Texas' statehood.