Aproximació molecular a l'estudi de l'home

Abstract

The application of molecular studies to reconstruct the history of the human species has become a powerful to01 for ascertaining either the evolutionary pathway or the timing of evolutionary events. Both long term and short term evolutionary problems may be analyzed, although only the long term, the human lineage, is treated here. Several levels of analysis allow us to compare among related species or different human populations in order to ascertain their degree of similarity from which an evolutionary tree may be reconstructed. These levels include, with increasing closeness to the genetic infomation (DNA), comparison using blood groups, immunological techniques, polymorphisms, sequence of aminoacids of proteins, sequence of nucleotides of DNA, and DNA hybridation. Since the complexity and diversity of techniques and of the mathematical treatment of results provided is very powerful in ascertaining the date of human origin, those and other molecular methods are being employed successfully to understand the problems related to migration and composition of ancient human populations.