Auteur : Richard Owen, "Darwin on the origin of species", 1860.

Date et contexte : 1860

Extrait : Buffon regarded varieties as particular alterations of species, as supporting and illustrating a most important principle -- the mutability of species themselves. The so-called varieties of a species, species of a genus, genera of a family, &c., were, with him, so many evidences of the progressive amount or degrees of change which had been superinduced by time and generations upon a primordial type of animal. Applying this principle to the two hundred mammalian species of which he had given a history in his great work, he believed himself able to reduce them to a very small number of primitive stocks or families. ^[1] Of these he enumerates fifteen: besides which, Buffon specifies certain isolated forms, which represent, as he forcibly and truly expresses it, both species and genus : ^[2] such are the elephant, rhinoceros, hippopotamus, giraffe, camel, lion, bear, and mole ^[3]. Palaeontology has since revealed the evidences of the true nature and causes of the present seeming isolation of some of these forms. Such evidences have been mainly operative with the later adopters and diffusers of Buffon's principle in the reduction of the number of primitive sources of existing species, and the contraction of the sphere of direct creative acts.