Ancient DNA study links the rise of agriculture to whiter skin, the rise of bowel problems

[joemm]

Scientists are now able to analyze ancient DNA from skeletons, revealing all sorts of new information about how humans evolved.

The latest discoveries in Europe have spurred a slew of new theories about how the rise of agriculture -- both crop farming and raising domesticated animals for meat -- shaped our genes. Researchers are linking the gene changes to why Europeans' skin lightened after migrating from Africa, and that adapting to consumer dairy products also gave us irritable bowel syndrome, according to the New York Times.

When people lived in what is now Europe made the switch from hunting and gathering to agriculture, likely spurred by a wave of immigrants from the Near East, their diet moved toward one dependent on wheat and other crops with nutrients their bodies weren't used to processing.

A gene called SLC22A4 helped humans digest more nutrients from wheat and other crops. But, it also introduced irritable bowel syndrome into European farmers' lives as well.

The study also adds a new theory to why Europeans' skin lightened. Previously, scientists thought it was to allow a greater intake of Vitamin D from sunlight. But the study suggests that agriculture reduced how much Vitamin D they consumed.

When living on a hunter-gatherer diet, the early Europeans got Vitamin D from the meat they caught. But when that was lessened in their diet, that source went away.

You can read more about the study here: Genome-wide patterns of selection in 230 ancient Eurasians http://www.nature.com/nature/journal/va ... 16152.html

-- Molly Harbarger

Fuente:http://www.oregonlive.com/business/inde ... he_ri.html

[skamada]

Pues sí, una de las cosas que se ha visto últimamente en genética de poblaciones es la aparición de celiaquía, intolerancia a la lactosa y empalidecimiento de la piel mucho más reciente de lo que se creía (ni 4.000 años), está claro que el Neolítico nos marcó bastante más que el Paleolítico a ese respecto y no queda en nosotros casi ni un ápice de Magdaleniense

[joemm]

Bueno, otro soporte de la dieta Paleo. Cuando el humano introdujo en su alimentación lácteos cereales - granos aparecieron cantidad de problemas.