11. The End and Revival of a Ridiculous Theory
In the early nineteenth century, French biologist Jean-Baptiste Lamarck theorized that physiological changes that an organism acquires during its lifetime can be passed on to its offspring. For example, if somebody works out at a gym to build huge biceps, he could pass on huge biceps to his children. The theory became known as Lamarckian Inheritance. It eventually became clear that Lamarck was wrong: traits are passed on through genes that are hard coded with their own instructions, subject to the occasional mutation.
The genes of a particular organism neither know nor care what traits and characteristics the organism acquired during its lifetime. One’s genes might pass on a predisposition for huge biceps if they were already coded for such a predisposition. However, doing arm curls at a gym will have no impact on whether one’s kids will have an easy time developing monster biceps. By the late nineteenth century, Lamarck’s theory had been thoroughly debunked, and only had a limited following within a circle of ridiculous quacks. Then the theory made a surprising comeback in the twentieth century in, of all places, Stalin’s USSR.