Brazilian Indian/non-Indian interactions and their effects

Abstract

A short review was made of the history of the Brazilian population, starting with the Asians who colonized the region 30,000-40,000 years ago, and continuing with evaluations of the European, African, and neo-Asiatic immigration. Social aspects of the contact situation between Brazilian lndians and the surrounding society were briefly considered, as well as quantitative estimates of the amount of Amerindian genes present in neo-Brazilians. Special emphasis, however, was placed in the inverse gene flow (neo-Brazilian genes into Amerindians). In this case, two methods which quantify the degree of such admixture were employed, and the one considered to give better estimates was chosen. Although the correlation obtained between these admixture values and the number of years of more permanent contact with non-Indians yielded a low number (perhaps due to deficiencies in obtaining precise figures concerning years of contact), a clear correlation was found between the admixture estimates obtained in 39 Brazilian lndian tribes or populations and their location in degrees of longitude west. This is probably a reflection of the general neo-Brazilian east-west colonization movement. At present it is difficult to ascertain the degree of biological and cultural homogeneity that will be reached by Brazilian populations in the future. lt is hoped, however, that a certain amount of diversity will be maintained, in a climate of mutual respect.