When you venture outside it’s easy at first glance to agree with Dr. Paley – it does seem as though an invisible watchmaker had a hand in creation. Everything appears to line up just right. Trees need water and – viola! – there is water. And that water must be in liquid form and wouldn’t you know it? We are just the right distance from the sun that most water on the planet is liquid. Temperatures stay just about right for mankind to be relatively comfortable. But if you pull back the carpet of dirt, it’s just as easy to discover that everything is not as calm and well planned as it appears. Lake beds, built up over years of calm sedimentation are upended, breaking through the earth like a tibia jutting out from a shin. Scrape around a bit and you might find stone relics of plants and animals that no man has ever seen. Where did they come from? God’s experiments?
These two pictures of a world of apparent pre-meditated order and calm juxtaposed against tumult and decay grew in centuries past into a natural philosophy called catastrophism. It’s champion was a grouchy Frenchman named Georges Cuvier who dared all others to prove him wrong. He was indeed proven wrong but only partly so. We will explore that in the next post.Georges
Cuvier was without question one of the first great scientists who relied on evidence rather than tradition and religion. Born in 1769, he held a multitude of posts in French government and has the distinction of having successfully – meaning that he kept his head attached to his body – maneuvered through three opposing French governments. His contributions to science are immense in the then emerging fields of comparative biology and paleontology. He rejected biological change as a means of speciation believing that the body functioned as a single unit and that any change to any part would render the whole unusable. His most notable contribution to animal science and evolution was the firm proof of the extinction of species. Prior to his arguments, fossils confused most people and were often regarded as remnants of living animals gone awry (think of John Merrick, aka the Elephant Man). Some believed that they never were animals but were fakes left by god to test the faith of believers. Cuvier worked with living and fossil elephant species and relatives and proved that modern elephants were different than fossilized elephants showing that other species were similar to those now extant and were now vanished from the planet.
Cuvier rejected gradual change in both animals and geology. He believed the earth to be old and earth history to be punctuated by periods of extreme upheaval. Massive floods, rapid mountain building, and geological tumult defined the end of each age. These catastrophes changed the landscape and displaced animals and plants. Cuvier called these periods of rest followed by catastrophes historical revolutions and used them to explain extinctions and the rise of new species. I’ve so far been unable to figure out how he thought new species with new traits rose. Without a god involved – Cuvier was adamant in avoiding religious overtones in his work – I’m not sure what he thought drove the rise of new species.
The Encyclopaedia Britannica makes an interesting observation that in many ways Cuvier represented the pivot between two eras. Though he largely invented comparative biology and paleontology his strong rejection of uniformitarianism and gradual change placed him firmly in the eighteenth century.
Rejecting catastrophism as a primary geologic model does not argue that the earth has seen cataclysmic changes. But a defining tenet of catastrophism is a denial of gradualism. It’s an argument that nothing changes, nothing moves, no geologic formation grows higher or is cut lower on a day to day, year to year, age to age basis. We understand now that this simply isn’t true. The one single universal idea in geology is that the forces that we see shaping our world today are the same forces that have been at work for millennia. There are tenets of catastrophism making a comeback. But don’t be swayed by creationists who glom onto the idea as justification for their opinions. That the earth has periodically seen rapid and tumultuous change doesn’t alter the plain fact that the laws of nature driving geologic and biologic changes don’t change and have been moving along quite nicely for a few billion years now.
Next we will look at the idea that supplanted catastrophism and is the basis of all science inquiry today – uniformitarianism.
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