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SCIENCE 



[N. S. Vol. XXXVI. No. 918 



mulattos is frequently not as dark as the negro 

 parent, and among the second (F,) genera- 

 tion one or several may be darker than the 

 darkest mulatto parent and one or several 

 lighter, without being quite as dark or as 

 light as the negro or white grandparent re- 

 spectively, suggests strongly that a complex 

 of factors is involved. 



The fact of the apparent histologic iden- 

 tity between brunette and mulatto skins; and 

 the further fact that under protracted ex- 

 posure to extremes of heat and sun the num- 

 ber of pigment granules is increased in white 

 skin, indicates that pigmentation (dark skin) 

 as evidenced in the negro is an instance of 

 the inheritance of an acquired character. 

 The least that makes a negro a negro is his 

 dark skin. Life-guards in September are fre- 

 quently almost as black. A negro is specifi- 

 cally such for mental perhaps more than for 

 physical characteristics. Moreover, the negro 

 originally hails from tropical regions; he has 

 been for unknown periods of time exposed to 

 the hot tropical sun. In foreign lands he 

 thrives best in hot climates. Pigmentation 

 in him has probably arisen as a response to a 

 protective demand against the rays of the sun, 

 just as whites now acquire a " tan " under 

 similar less extreme and less prolonged con- 

 ditions. This line of reasoning would appear 

 cogent enough, but unfortunately it can not 

 be experimentally tested. In the absence of 

 such test it must remain simply a speculation. 



Moreover, if Kingsley's quotation in " At 

 Last " of a description of the inhabitants of 

 Saba by the Bishop of Antiqua is to be 

 trusted, the results of one of nature's experi- 

 ments along these lines militates against the 

 speculation. The Bishop spoke of them, 

 Kingsley says, as " virtuous, shrewd, simple, 

 healthy folk, retaining, in spite of the tropic 

 sun, the same clear white and red complexion 

 which their ancestors brought from Holland 

 two hundred years ago — a proof, among many, 

 that the white man need not degenerate in 

 these places." ' 



The two most obvious explanations of negro 



*P. 23 (ed. 1910, Macmillan & Co.). 



deep pigmentation are the one outlined above, 

 i. e., acquired in response to a peculiar en- 

 vironment and transmitted; and as inherited 

 from anthropoid ancestors. The evidence 

 yielded by the inhabitants of Saba of the 

 West Indies renders inadmissible the first. 

 What facts support the latter interpretation ? 



In the first place the negro is a primitive 

 type of man, as indicated by numerous ana- 

 tomic marks (e. g., relative length of arms 

 and legs, male external genitalia — prepuce 

 covers glans — shape of nose, use of hallux, etc.) 

 which are more or less infantile European 

 characters. He apparently stands much closer 

 in the evolutionary scale to the anthropoid 

 apes, with pigmented faces. The negro may 

 have inherited his dark skin frorii his pig- 

 mented pre-man ancestors. He may be ha- 

 bitually an inhabitant of the tropics because 

 he alone could survive in that climate, or be- 

 cause he was best suited and thus more com- 

 fortable there. The dark-skinned races, like 

 the Italians and Spanish, and finally the 

 brunettes of the Anglo-Saxon race, may owe 

 their pigmentation to negroid ancestry. The 

 connecting link may well have been the negro 

 slaves of Roman times, and the conquer- 

 ing Teutons. 



Moreover, anthropoid ancestry may account 

 more directly, i. e., without negroid inter- 

 vention, for the pigment of " whites " ; or, as 

 in numerous other instances, so in the case 

 of pigmentation, we may simply be dealing 

 with an instance of parallelism. Similar re- 

 sults of varying degrees may have been at- 

 tained under the influence of similar condi- 

 tions, at various times and various places. It 

 seems impossible at present to arrive at a defi- 

 nite conclusion. Complete knowledge on this 

 point may perhaps never be forthcoming. 

 The above discussion indicates the possible 

 origin of a multiplicity of factors in skin- 

 color determination. However, regarding the 

 histologic similarity between light and deep 

 pigmented skins and a measure of segrega- 

 tion among the children of black-white crosses 

 there remains no question. 



H. E. Jordan 



University of Virginia 



