Chapter 13: Pre-History (Genome)

•The surprising similarity of embryological genes in worms, flies, chicks and people sings an eloquent song of common descent.

• D N A is a code written in a simple alphabet — a language. We compare the vocabulary of developmental genes and find the same words.

• On a completely different scale, but with direct analogy, the same is true of human language: by comparing the vocabularies of human languages, we can deduce their common ancestry.

• Historians may lament the lack of written records to document the distant, prehistoric past, but there is a written record, in the genes of living organisms.

•Basque, Navajo, and some Chinese tongues share an affinity not belonging to the Nostratic super-family of languages.

• It is speculated that Basque was once spoken in a larger area than currently, as shown by place names and Cro-Magnon cave paintings.

• There is a possibility that speakers of these tongues are actually descended from mesolithic people.

• Luigi Luca Cavalli-Sforza gathered data on common variations in simple genes to try and uncover any patterns.

• Five different contour maps of gene frequencies were uncovered within Europe – one gradient from south-east to north-west, one steep hill to the north=east, etc..

The most intriguing map was a steep little peak coinciding almost exactly with the greater (original) Basque country in northern Spain and southern France.

•There is a gene on chromosome 13 called BRCA2 that has been linked to breast cancer.

• This gene was first discovered by studying Icelandic families with a high incidence of breast cancer.

• Jewish people have a higher incidence of developing breast cancer due to a mutation in the BRCA2 gene.

• The ability to digest alcohol and milk are determined by genes on chromosomes 4 and 1 respectively.

•By looking at sixty-two separate cultures, two biologists were able to decide between these theories.

• They found no good correlation between the ability to drink milk and high latitudes, and no good correlation with arid landscapes.

• But they did find evidence that the people with the highest frequency of milk-digestion ability were ones with a history of pastoralism.

• The evidence suggests that such people took up a pastoral way of life first, and developed milk-digesting ability later in response to it.

"A gilded No is more satisfactory than a dry yes" - Gracian