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180k-Year-Old Mutation Allowed Humans To Become Vegetarians, Move Out of Africa
An anonymous reader writes "Early humans were able to move from Africa after a single genetic mutation allowed them to become vegetarians, scientists claim. The switch, which allowed humans to process vegetables, meant that humans were able to move away from water sources and spread across the continent. A team of geneticists compared DNA sequences from a variety of people around the world to see how different populations relate to one another and when they have gone their separate ways. The scientists found that a key genetic variant gave humans the ability to convert fats from plants into essential nutrients for the brain."
Wouldn't that be omnivores?
... being able to eat vegetables is not unusual for ANY monkey or ape. What is more if not most interesting is a genetic mutation which allows us to eat grains. Chimpanzees, for example, simply cannot process grains and as far as I have heard humans are the only primates which can.
unless they mutated away to live without water, humans did NOT move away from water.
I'm pretty sure they still lived around water. Rivers, Springs, Oases, Wells, whatever, but they needed the water.
But what do i know?
Be seeing you...
The scientists found that a key genetic variant gave humans the ability to convert fats from plants into essential nutrients for the brain."
To this?
180k-Year-Old Mutation Allowed Humans To Become Vegetarians, Move Out of Africa
People who don't know their scientific terms mis-quote scientific articles. News at 10.
We'll go in order...
mutations are so rarely beneficial
The vast majority of the mutations that are widespread through the population are either benign or beneficial. The ones that aren't don't stick around in the gene pool long enough to become widespread. It's the other half of the selection pressure you mentioned: The selection pressure culls bad mutations out quickly, so the good (or at least ineffective ones) are all that's left. This is definitely a case of history being written by the victors: The bad mutations don't usually stick around long enough to be noticed (in long-term history).
So how do they know it was a mutation?
Because some folks have it, and other folks don't. From the geographic distribution of where the haves and have-nots are, combined with the prevailing theories about human movements, the researchers can estimate what genetic group first got the change.
one mutated birth isn't going to suddenly diffuse across an entire species.
It doesn't happen suddenly. That one mutation spreads through one family, who suddenly has the ability to survive without eating fish (substituting vegetables, instead). Over the next thousand years or so, that family (and the associated mutation) spread across the local region, and the knowledge of "it's okay to eat vegetables" spread with it. Since that group could wander further (carrying longer-lasting vegetables rather than fish), they spread farther than other groups, until they eventually became dominant.
How one random gene in one birth suddenly afflicts an entire population?
Just to be clear, it doesn't. The one random change will be in one family line, and only really become widespread if it allows the family to outgrow the rest of the population, or if the the rest of the population dies off.
You do not have a moral or legal right to do absolutely anything you want.
The Slashdot headline is wrong and the initial website it links to has a wrong headline.
If you read the scientific paper, it says the mutation happened about 85,000 years ago, not 180,000 years ago. This makes it logically consistent with other biological discoveries, archaeological finds etc.
Basically, I don't understand this article.
The problem isn't the article. It's your limited understanding of evolution and genetics. :-)
According to modern evolutionary theory, mutations create ALL change. Most mutations don't do something favourable, or really actually probably don't do anything at all, but some of them are favourable and those individuals go onto spread that gene more effectively than their peers until many many generations later, this gene has spread throughout the species (or the region, or the tribe, etc).
If a tribe of ancient humans gradually gained the ability to survive without meat, and a major event such as volcanic eruption or something killed off the local food staple, the tribe that could survive for years without meat might be the only survivors in the entire area. If the species is isolate to that area, they could plausibly be the only survivors of the species.
In this way it is actually possible for the entire species to gain a trait in just a few generations. Or, a mutation can gradually make its way into cultures in a more limited sense.
For example, genetic analysis suggests that ALL blue eyed individuals are descendants from a single individual with a unique mutation about 6-10,000 years ago. People with brown eyes have a huge variety of genes that affect pigmentation, whereas all individuals with blue eyes have a very specific sequence that controls it, which, along with mitochondrial DNA surveys, leads researchers to conclude the bit about a single individual.
Pretty cool, eh?
I'm a proxy vegetarian via eating grass and corn fed cows!
The headline is flamebait. The editors know the Slashdot nerds will see the term "vegetarian," become furious, and click on the article, and post furious posts, which will generate more furious posts and more page views. Profit!
TFS was worse than the normal FS. First off, the "vegetarian" bit. Now that I've RTFA, we were omnivores, but we needed fish or our brains wouldn't develop propery, so we were stuck living near the ocean. Once we could live without fish we could live anywhere.
It had nothing to do with vegetarians, the sumitter is probably one of those PETA vegan nuts.
Free Martian Whores!
"one mutated birth isn't going to suddenly diffuse across an entire species."
you're right:
1. what happens is those without the mutation die or have less children or no children, or are confined to one small environmental niche
2. while those with the mutation live longer or have more children or move over a wider range taking advantage of a wider range of food
and you're wrong:
1. it could start with one single mutation in one individual
2. it does diffuse across an entire species: that's what sex is for
3. it does happen suddenly, on the time scale of geological time
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
African Americans love Chicken
Everyone loves chicken, you insensitive clod!
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
(1) is often referred to as a "founder event", particularly by people like Ken Nordtvedt, who studies human migrations through genetics as a hobby.
(3) There are an estimated 200 mutations in the Y chromosome alone every generation, be they extra copies/deletions of something (known as a short tandem repeat) or a change in a single nucleotide (known as a single nucleotide polymorphism). Most of this is in "junk" DNA (now known to be control sequences and metadata - a prediction many had made for two or three decades at least, and I've been making on Slashdot for 10+ years) but it's also found in coding sequences. Most genealogy (eg: by Family Tree DNA) is done with the "junk" DNA, most prior health work (eg: by 23AndMe) has been done on the coding sequences but expect that to change to everything at some point. Studies on population migrations suggest one mutated birth (such as the ability to digest milk) can spread over most of the species in 6-7 thousand years, and markers associated with (and do not predate) the Vikings can be found in significant quantities in most inhabited continents after far less time than that. On geological timescales, this qualifies as the Newtonian concept of the infinitesimal.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)