Building Stones to a Chemistry of Evolution

Abstract

The object of this paper was to point out that evolution depends to a large extent on the formation of new kinds of hereditary units, e.g., genes. Such formation can be caused only by a chemical reaction, and therefore must follow chemical laws. While the actual reagents involved are entirely unknown, some general laws can be applied successfully, and seem to justify the following statements: The frequency of the creation of a new hereditary unit in any given species is proportional to the number of individuals born per year. This is borne out by the evidence that of the plants of North America, the rare families have few species, and the common families have many species. The frequency of the creation of a new hereditary unit in any given species is greater in warmer climates because chemical reactions proceed more rapidly at higher temperatures. This is borne out by the evidence that among reptiles, there are about eight times as many species in tropical climates as in moderate climates, while with mamm...