"Anthropological authority was further quoted for primitive man being red-haired, and Darwin and Lord Avebury for atavism from crossing being shown by the appearance of red feathers in the offspring when interbreeding white and black breeds of poultry."
[...].
"As to the atavism of red hair, there is a long list of authorities. The earliest must be Eusebius, an ecclesiastic who by a remarkable anticipation deduced, from the sporadic distribution of red hair among all nations of the earth, that Adam was red-haired! The celebrated Broca noticed this same distribution, and said red hair arose by preference from certain "croisements." Topinard ... opined that red hair in Europe came from reversion to a primitive rufous race, now extinct, living on either side of the Urals. There is also evidence that red hair can result to-day from crosses, not only in poultry, but in man. 'Pruner Bey and others have noted that dark Spaniard and American Indian can procude a red-haired offspring, which appears as another instance of a pigment breakdown following hybridization.'"
W.C. Rivers, "Red Hair and Tuberculosis", THE PRACTITIONER (June 1921 at 419-25) at 420-21.
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