American Indians with African ancestry outdid 'full bloods' in reproductive terms in the early 1900s, despite the odds being against them, according to a new study by Michael Logan from the University of Tennessee in the US. Their increased fertility occurred at a time when things were not going particularly well for full bloods either - in social, economic and health terms. The work is published online in Springer's journal, Human Ecology.
One of the major characteristics of the demographic history of American Indians is interethnic marriage. While the majority of these unions involved Indian women and Caucasian men, a sizeable number occurred between Indians and African Americans. The children of these bicultural marriages were "mixed bloods" who in turn typically married non-Indians or other mixed bloods.
Logan investigated factors affecting the fertility of American Indians and explored why those with African ancestry enjoyed particularly high fertility, using data from the 1910 Census on American Indians in the US and Alaska. His analyses show that a host of interrelated factors affected the reproductive success of these people, including genetics, cultural practices and the socio-economic and health environments they lived in.
Based on the reproductive histories of 295 women of mixed Indian-black and Indian-black-white heritage, Logan found that Indian-black marriages proved to be advantageous in terms of fertility, fecundity (the average number of births per woman) and offspring survival.
The lower infant-childhood death rates recorded for mixed couples, together with variations in sterility and fecundity, help to elucidate why mixed bloods as a population grew so rapidly in comparison to full bloods during the late nineteenth and early twentieth century, explains Logan.
He concludes: "The fact that mixed blood Indians with African ancestry did so well reproductively speaks to their resolve to make the best of life for themselves and their children, in a social and political milieu marked by pronounced racism against all peoples of color. The data clearly demonstrate that those who faced the most challenges from racism also fared well reproductively, despite the many hurdles they encountered."
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Logan MH (2011). American Indians with African ancestry: differential fertility and the complexities of social identity. Human Ecology. DOI 10.1007/s10745-011-9439-2