An open access publication of the American Academy of Arts & Sciences
Winter 2002

The biology of race

Ernst Mayr
View PDF

Ernst Mayr is Alexander Agassiz Professor of Zoology, Emeritus, at Harvard University. His work contributed to the synthesis of Mendelian genetics and Darwinian evolution, and to the development of the biological species concept. The author of many books, including “Animal Species and Evolution” (1963) and “The Growth of Biological Thought” (1982), Mayr in 1999 received the Crafoord Prize from the Royal Swedish Academy of Sciences for his contributions to our understanding of biological evolution. Mayr has been a Fellow of the American Academy since 1953.

There are words in our language that seem to lead inevitably to controversy. This is surely true for the words “equality” and “race.” And yet among well-informed people, there is little disagreement as to what these words should mean, in part because various advances in biological science have produced a better understanding of the human condition.

Let me begin with race. There is a widespread feeling that the word “race” indicates something undesirable and that it should be left out of all discussions. This leads to such statements as “there are no human races.”

Those who subscribe to this opinion are obviously ignorant of modern biology. Races are not something specifically human; races occur in a large percentage of species of animals. You can read in every textbook on evolution that geographic races of animals, when isolated from other races of their species, may in due time become new species. The terms “subspecies” and “geographic race” are used interchangeably in this taxonomic literature.

This at once raises a question: are there races in the human species? After all, the characteristics of most animal races are strictly genetic, while human races have been marked by nongenetic, cultural attributes that have very much affected their overt characteristics. Performance in human activities is influenced not only by the genotype but also by culturally acquired attitudes. What would be ideal, therefore, would be to partition the phenotype of every human individual into genetic and cultural components.

Alas, so far we have not yet found any reliable technique to do this. What we can do is acknowledge that any recorded differences between human races are probably composed of cultural as well as genetic elements. Indeed, the cause of many important group differences may turn out to be entirely cultural, without any genetic component at all.

Still, if I introduce you to an Eskimo and a Kalahari Bushman I won’t have much trouble convincing you that they belong to different races.

In a recent textbook of taxonomy, I defined a “geographic race” or subspecies as “an aggregate of phenotypically similar populations of a species inhabiting a geographic subdivision of the range of that species and differing taxonomically from other populations of that species.” A subspecies is a geographic race that is sufficiently different taxonomically to be worthy of a separate name. What is characteristic of a geographic race is, first, that it is restricted to a geographic subdivision of the range of a species, and second, that in spite of certain diagnostic differences, it is part of a larger species.

No matter what the cause of the racial difference might be, the fact that species of organisms may have geographic races has been demonstrated so frequently that it can no longer be denied. And the geographic races of the human races– established before the voyages of European discovery and subsequent rise of a global economy–agree in most characteristics with the geographic races of animals. Recognizing races is only recognizing a biological fact.  .  .  .

Access the full issue here.