On this date, the naturalist Georges-Louis Leclerc, count de Buffon was born in Montbard, France. Buffon is best remembered for his great work Histoire naturelle, générale et particulière(1749-1778: in 36 volumes, 8 additional volumes published after his death by Lacépède). It included everything known about the natural world up until that time and was translated into many different languages, making him the most widely read scientific author of the day, equaling Rousseau and Voltaire. Buffon’s views influenced the next two generations of naturalists, including Jean-Baptiste Lamarck and Charles Darwin.
Buffon was one of the first philosophers to grapple with the questions of evolution, both of Earth and of living creatures. At the time, church doctrine insisted that Earth was only six thousand years old and that each type of creature had been made independently by a Creator. He proposed instead around 1778 that the Earth was hot at its creation and, from the rate of cooling, calculated its age to be 75,000 years, with life emerging some 40,000 years ago.
Buffon noted that despite similar environments, different regions of the world have distinct plants and animals, a concept later known as Buffon’s Law, widely considered the first principle of biogeography. He made the radical conclusion that species must have both “improved” and “degenerated” (evolved) after dispersing away from a center of creation. He also asserted that climate change must have facilitated the worldwide spread of species from their center of origin. Buffon also proposed, in sharp contrast to his contemporary Carolus Linnaeus, that species are defined not by simple similarity of appearance but by reproductive fertility over time.