Origin’s Chapter I: How Breeders Work Their Magic

Abstract

Darwin begins his “one long argument” not in the natural world of the deep past but – surprisingly and, for some readers, disappointingly – on the present-day world of the farm, providing a detailed look at domesticated plants and animals as well as the humans who breed them. Darwin’s opening chapter divides roughly into two halves. In the first half, Darwin surveys the amazing variability of plants and animals under domestication and some of the main causes of that variability. In the second half, he turns from variation to selection: the picking for breeding of the individual dogs or pigeons or cabbages or whatever which are the fastest or the strongest or the most colorful or the tastiest or whatever, in the hopes that those attractive variations will be inherited by offspring. It is mainly through selection of inheritable variation, Darwin argues, that humans have created so many and such diverse domesticated varieties of plants and animals, suited so splendidly to human needs and desires. A large part of being able to follow Darwin’s reasoning through the densely fact-packed paragraphs in this chapter lies with seeing where, in his view, it’s all going: namely, the laying down of the foundations for an analogical argument linking the selective breeding-into-being by humans of new varieties, or “artificial selection,” with a comparable process in nature capable of producing not merely new varieties but new species – what he will call, to flag the analogy, “natural selection.” It also helps to be alert to a number of ideas that Darwin held but which modern biologists reject, such as the notion that domestication itself induces animals and plants to become far more variable than they are in the wild, and the idea that characters acquired in the course of an individual’s lifetime can be inherited (so-called “Lamarckian inheritance”).