Extinctions: Georges Cuvier (1 of 2)

By the 1700s, fossils had been inducted into the living world. Instead of being produced by rocks themselves, fossils were recognized as the remains of animals or plants. They looked too much like particular living species to be anything else. As the eighteenth century wore on, some fossils emerged that could not be tied so neatly to the known living species. Elephants, for example, had left fossils in Italy, where they could no longer be found. Yet elephants still lived in Africa, and naturalists assumed that other fossils had living counterparts of their own in some remote part of the world. But, at the end of the century, a French naturalist offered an astonishing revelation: some species had actually vanished from the face of the Earth.

Georges Cuvier (1769-1832) joined the fledgling National Museum in Paris in 1795, and quickly became the world’s leading expert on the anatomy of animals. He then used that knowledge to interpret fossils with unprecedented insight. Legend has it that sometimes even a few fragments of bones were enough for him to reconstruct the complete anatomy of a previously unknown species with uncanny accuracy. Armed with this expertise, Cuvier waded into the debate over whether species could become extinct.

This print shows the recovery of the first mosasaur fossils in 1780. Cuvier used the fossils to support his radical ideas on extinction.

A few earlier naturalists, such as Buffon, had argued that species might become extinct. But for many people in Cuvier’s day, the idea of extinction was religiously troubling. If God had created all of nature according to a divine plan at the beginning of the world, it would seem irrational for Him to let some parts of that creation die off. If life consisted of a Great Chain of Being, extending from ocean slime to humans to angels, extinctions would remove some of its links.

• Cuvier image courtesy of Dennis O’Neil, Palomar College.
• Mosasaur recovery image courtesy of Oceans of Kansas.