GENOME Entry #5: Chromosome 13 - Pre- history

Matt Ridley first begins with saying how there is a similarity of embryological genes in worms, flies, chicks, etc and this shows that there is a common descent among this species because of DNA. He makes a comparison of this to human languages, and how by comparing the vocabularies of human languages we can find out their common ancestry, just like how we are look at embryonic history right now. In the 1980s Luigi Luca Cavalli-Sforza wondered if linguistic similarities coincide with genetic ones. By gathering data on the common, known variations in simple genes and doing clever statistical tricks called principal components analysis with the resulting data, Cavalli-Sforza uncovered five different contour maps of gene frequencies within Europe. In a study with chromosome 1 that has the gene lactase, the evidence suggests that such people took up a pastoral way of life first and developed milk-digesting ability later in response to it. This provides an example of a cultural change leading to an evolutionary.