In the last two decades, genetic research has gone through a technological revolution and is now producing unprecedented amounts of data on individuals and human groups. The interpretation of data from human evolutionary genetics—along with sources from history, archaeology, linguistics, anthropology, and paleontology—is changing our understanding of human history.
We all originate from Africa, where our ancestors lived over 100,000 years ago. We all belong to the same species, Homo sapiens, and our DNA is more than 99% identical. The amazing diversity we see as we look at each other cannot be analyzed according to human "races." Our genetic diversity is primarily individual and not in-between populations. Some of these very small genetic differences in our species, however, follow geographic patterns, which reflect previous environmental challenges, cultural encounters, and population movements. They are a product of constant interactions between genes, environments, and social conditions.
However, research on human biological variation still raises difficult scientific, political, social, and ethical questions. These are related to the language, methods, and theories employed for the interpretation and communication of results, as well as to access to human biological material.