Dr Morton on Hi^brid Animals and Plants. 287 



Could we trace back the origin and history of various 

 other species, we should, in all probability, arrive at the very 

 same result ; for it appears to be a law of nature, that the 

 faculty possessed by different species of animals of producing 

 fertile hybrid offspring, is in proportion to their aptitude for 

 doinesticity. 



Now, since man possesses this aptitude in the highest de- 

 gree, being, as Blumenbach expresses it, the most domestic 

 of animals, it would be nothing singular if he possessed the 

 power of fertile hybridity, even if the human family should 

 prove to embrace several distinct species ; because, as we 

 have fully shewn, this phenomenon is not unfrequent among 

 animals whose specific, and even generic diversities, are un- 

 questionable. If, therefore, domestication, or, as we have 

 termed it, the aptitude for domesticity, explains the fact in 

 one instance, it certainly does so in the other, more espe- 

 cially since fertile reproduction has ceased to be evidence of 

 identity of species. 



A word with respect to the theory of repugnance. The 

 same phenomena, moral as well as physical, take place, to a 

 certain extent, among men as among animals ; for the repug- 

 nance of some human races to mix with others, has only been 

 partially overcome by centuries of proximity, and, above all 

 other means, by the moral degradation consequent to the 

 state of slavery. Not only is this repugnance proverbial 

 among all nations of the European stock among whom ne- 

 groes have been introduced, but it appears to be almost 

 equally natural to the Africans in their own country, towards 

 such Europeans as have been thrown among them ; for with 

 the former a white skin is not more admired than a black one 

 is with us.* 



* See the travels of Hawkins, Browne, Burkhardt, Caillet, (fee, for abundant 

 evidence of this fact. 



I must here be permitted to offer a single additional remark. It is obvious 

 that while cultivation produces obvious changes in some animals, its influence 

 has had little or no effect on others ; for example, the ass, the rat, and the mouse, 

 among quadrupeds, and the peacock and guinea-fowl among birds. These spe- 

 cies have been domesticated from immemorial time, in all latitudes, under eviery 

 conceivable variety of circumstances. Among wild birds and quadrupeds, ou 



