May 13 - Remembering Georges Cuvier

    Posted on May 13, 2022

This is an update of my post published on May 13, 2011:

Georges Cuvier named the pterodactyl and the mosasaurus. He opposed the idea of evolution. He proved that species of animals have gone extinct. He believed that the “original people” were white (Caucasian). He established the fields of comparative anatomy and paleontology.

Like so many scientists who lived and worked a long time ago, Cuvier had some really good ideas that established or revolutionized branches of science—but he also had some ideas that, since his death, have been shown to be utterly wrong. 

(And racist!)

When you look at the work of Cuvier, a French biologist and paleontologist who died on this day in 1832, you can't help thinking - or at least hoping - that he would have changed many of his incorrect views if he could've seen the evidence we humans have gathered since his time.

For example, in opposing evolution—the idea that populations of animals change over time—Cuvier was opposing the theories of his contemporaries, Lamarck and Geoffroy Saint-Hilaire. And, we now know, those theories were incorrect. Charles Darwin's theories of common descent and of evolution driven by natural selection—which have been added to, now that we know about genes and DNA, and which TONS of evidence show are essentially correct—wouldn't be published until more than 20 years after Cuvier died.

Fossils drawn by Georges Cuvier

As the saying goes, in science we stand on the shoulders of giants. Today's average 11 year old kid knows more science than the most brilliant Ancient Greek natural philosopher, and a college freshman pre-med student knows more Bio, probably, than Cuvier! Still, Cuvier is one of those giants of intellect and endeavor upon whose work biology is built.

Cuvier believed in catastrophism...

Cuvier studied fossils of animals that no longer exist today, such as the wooly rhinoceros and the mammoth, and he came to believe that they went extinct due to some sort of natural catastrophe. Geologists who put forth the theory of catastrophism explained geological formations through catastrophes, too; for example, the carving of canyons and valleys might be explained by mighty floods.

The opposite of catastrophism is uniformitarianism. This is the theory that geological features can be explained by forces we can see today, acting gradually over years, decades, centuries, millennia. Under this theory, valleys and canyons (for example) are carved slowly and gradually by the slow movement of glaciers, or by many rainstorms and erosion events.

Glaciers carve U-shaped valleys.
Rivers tend to carve V-shaped valleys,
but of course over the course of time,
many of these valleys widen.

Today geology is based on uniformitarianism and catastrophism, together. Earthquakes and volcanoes seem like natural catastrophes to us, but to a geologist, these and other tectonic forces are constant enough to be an important, almost continuous, part of land formation and shaping. Erosion tends to be almost continuous, too. Catastrophes such as super-volcanoes, major storms and floods, and of course huge meteors (perhaps asteroids or comets) that impact the Earth all happen occasionally and sculpt the land as well. 

Biologists and geologists have worked out together that (almost certainly) at least some animal extinctions have been caused by huge tectonic or impact events. (And of course, extinctions of some species of plants and other organisms would share these same causes.)

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