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How Farming Reshaped Our Genomes
sciencehabit writes "The earliest farmers may not have been built for the profession. They may have been unable to digest starch and milk, according to a new ancient DNA study of a nearly 8000-year-old human skeleton from Spain (a hunter-gatherer who had dark skin and blue eyes). But these pioneers did already possess immune defenses against some of the diseases that would later become the scourge of civilization. The findings are helping researchers understand what genetic and biological changes humans went through as they made the transition from hunting and gathering to farming."
http://news.sciencemag.org/sit...
Who says he let his hair and beard grow long? What evidence from the skeleton would have led to this conclusion?
It means not being too choosy what you om-nom-nom on when the going is lean. Which likely means eating things which may have various parasites, mold spore, other fungi, even partially decomposed. "What luck! A partially decomposed squirrel with red rashes all over its body! Num!" That which didn't kill them, indeed make them stronger (those which survived, that is.)
In today's scrubby, scrub scrubbed world of clean, inspected and otherwise near perfect world of meat, dairy and produce, we're not challenging our bodies very much. Further, we appear to be adapting to eating sugary, fried or other highly processed food, which means we say "Ewww!" when presented with ethnic foods we haven't seen before, which include the globby or wiggly bits of animals we don't see in the meat case at the market (which traditionally were the best parts, unlike the muscle which was often left behind.)
Somewhat disconcerting how we haven't turned into beings which are entirely fed by capsule, a la the Jetsons "Oh, dear, I've overcooked the steak and potatoes pill."
Fortunately, infants keep picking up dead bugs off the carpet and chewing on them, which gives them some bit of a test in developing their immune systems.
A feeling of having made the same mistake before: Deja Foobar
What is this silliness, that "humans" in the broad, blanket sense could not digest starch? Feh.
We already know from analysis of Neanderthal remains that they could digest starch, and did in fact eat things like starchy tubers and grains. By 8000 years ago, it's generally accepted that the Neanderthals were no more, at least as a distinct population, and that any remaining Neanderthal-specific genes had been absorbed by the wider Cro Magnon population. (Interestingly, it sounds like the Neanderthal genes might give their descendants, i.e. non-sub-Saharan-Africa humans, extra resistance to viral infection.)
This study, where evidence from one individual is extrapolated to the entire human population, sounds silly in the extreme. "One Size Fits All!" never really does.
Cheers,
"What in the name of Fats Waller is that?"
"A four-foot prune."
At the time, we humans needed a steady food supply. Hunting and foraging is too sporadic - and hence why we developed this ability to gain fat easily and it's a bitch to get rid of it. Feast or famine.
Agriculture and the the high calorie grains like wheat and corn allowed us to survive and develop a society where we have farmers and other professions.
Now that model is obsolete in the modern Western World, we are paying the price of our inability to adjust our taste buds.
High calorie food tastes great! But we're not suffering from food shortages or doing enough physical work to justify those tastes.
Wheat and corn didn't fuck us - our inability to judge our caloric needs is what screwed us.
The composition of the milks are different. Cow milk contains more protein in general, and some proteins that are not found in human milk. Some people are unable to process those proteins. Also, intolerance to milk of any kind generally occurs later in life. If an individual were not able to digest it in infancy they would die and their genes would not be passed on. Perhaps with modern medical science, they would live, but this would not have been the case thousands of years ago.
All mammals are, by definition, born with the ability to digest milk, therefore they have the genes to do that. It can happen that those genes are epi-genitically turned off in adults that are not exposed to milk. However, the genes would be still there.
The genes for digestion are still there, yes, but they shut off after childhood unless you have a specific genetic mutation that allows lifelong production of lactase. Source 1, source 2.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
Humans, like most mammals, can universally digest lactose in childhood. Also, like most mammals, the gene for producing lactase largely shuts down in adulthood, since in nature, it's largely unneeded and a waste of energy resources. People descended from milk-drinking cultures (mostly Europeans) have variations of a gene that prevent lactase production from turning off in adulthood.
Of course, this has little to nothing to do with breasts, since humans are the only primates that have visible breasts when not nursing their newborn young, and even then they are much, much smaller than in humans. It's most likely they exist purely for sexual signalling (like a peacock's tail), since their size is mostly irrelevant to their function in child-rearing.
If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
Incas had potatoes. It does not need to be a grain. But starchy foods are usually more effective in useful energy generated per acre.
In the Pacific breadfruit was the staple. However it was so easy to grow there that there wasn't a lot of work 'farming' anything.