From Wikipedia so that you can feel you might still be correct..
while other, mainly southern Cushitic groups, were assimilated into Maasai society. The resulting mixture of Nilotic and Cushitic populations also produced the Kalenjin and Samburu
From Wikipedia so that you can feel you might still be correct..
while other, mainly southern Cushitic groups, were assimilated into Maasai society. The resulting mixture of Nilotic and Cushitic populations also produced the Kalenjin and Samburu
stayed forever wrote:
If you move to altitude and have a child with a woman that has been there for millennia your child has a very good chance of inheriting those traits. Immediately.
Only a randomly selected half of those genes.
stayed forever wrote:
From Wikipedia so that you can feel you might still be correct..
while other, mainly southern Cushitic groups, were assimilated into Maasai society. The resulting mixture of Nilotic and Cushitic populations also produced the Kalenjin and Samburu
And where did the Nilotic and Cushitic people come from?
Hint: Say the word "Nilotic" slowly.
probability ain't your friend wrote:
stayed forever wrote:If you move to altitude and have a child with a woman that has been there for millennia your child has a very good chance of inheriting those traits. Immediately.
Only a randomly selected half of those genes.
And then that kid has children with other people that have a pretty good chance of having those genes... and it spreads like wildfire through the population.
My best guess would be that they have a higher per capita ratio of skinny people who live an active lifestyle and don't eat fast food. If you've ever stood next to an East African runner, they generally have smaller frames than other people.
So if you combine that with some of those people having speed, and some of those same people having a good aerobic capacity then that explains things.
I have an easier time believing the above than that they have super high aerobic capacities, but not because they're skinny.
Brad Wilkins wrote:
stayed forever wrote:From Wikipedia so that you can feel you might still be correct..
while other, mainly southern Cushitic groups, were assimilated into Maasai society. The resulting mixture of Nilotic and Cushitic populations also produced the Kalenjin and Samburu
And where did the Nilotic and Cushitic people come from?
Hint: Say the word "Nilotic" slowly.
And the Cushitic supply the altitude adaptation. Not very hard to follow.
stayed forever wrote:
probability ain't your friend wrote:Only a randomly selected half of those genes.
And then that kid has children with other people that have a pretty good chance of having those genes... and it spreads like wildfire through the population.
No, if you have 50% of the ABC genes and your spouse has 50%, your kids... will still have 50%. If you have mostly Kalenjin ancestry, you're missing most of the ABC genes. And if there are recessive traits in the ABC gene pool, they may never stick in the Kalenjin population.
That's why evolution takes a very long time. Good genes don't spread like wildfire, they are removed almost as easily as they are added.
Henrik Larsen pretty much ruled out altitude being the determining factor in East African running dominance. He tested a group of sedentary Kenyan kids and compared their results to a group of sedentary Danish kids. No difference in aerobic capacity or performance.
Then he trained both groups for 12 weeks. They improved in a similar magnitude, suggesting that there was no difference in trainability between groups. There was also no difference in muscle fiber type between groups.
However, they did find a significant difference in running economy. The Kenyan boys had lower running economy when compared to the Danish boys, both before and after 12 weeks of training. This difference was attributed to the significantly lower mass of the shank in the Kenyan boys. It has been shown that for every 100g of extra mass on the lower limb, we have a 1% increase in cost of locomotion. So the lighter, thinner legs of the Kenyan boys reduced their cost of locomotion.
He basically concluded that the dominance of Kenyan runners was down to significantly lower running economy which was primarily due to their longer, thinner legs.
REFERENCE:
Larsen, H. (2003) Kenyan dominance in distance running. Comparative Biochemistry and Physiology Part A. 136; 161-170
oldtiger wrote:
they have a higher per capita ratio of skinny people who live an active lifestyle
undernourished + work hard = elite at energy management
if you tried to raise a western kid the way most EA distance elites grew up, the state would probably take your kid away.
probability ain't your friend wrote:
stayed forever wrote:And then that kid has children with other people that have a pretty good chance of having those genes... and it spreads like wildfire through the population.
No, if you have 50% of the ABC genes and your spouse has 50%, your kids... will still have 50%. If you have mostly Kalenjin ancestry, you're missing most of the ABC genes. And if there are recessive traits in the ABC gene pool, they may never stick in the Kalenjin population.
That's why evolution takes a very long time. Good genes don't spread like wildfire, they are removed almost as easily as they are added.
They spread if the selection for them is rigorous, which it was.
stayed forever wrote:
probability ain't your friend wrote:No, if you have 50% of the ABC genes and your spouse has 50%, your kids... will still have 50%. If you have mostly Kalenjin ancestry, you're missing most of the ABC genes. And if there are recessive traits in the ABC gene pool, they may never stick in the Kalenjin population.
That's why evolution takes a very long time. Good genes don't spread like wildfire, they are removed almost as easily as they are added.
They spread if the selection for them is rigorous, which it was.
How was the selection rigorous? Anyone can live comfortably at altitude.
No it does not spread like wildfire, even with selective breeding. The math is easy to figure out.
stayed forever wrote:
Brad Wilkins wrote:And where did the Nilotic and Cushitic people come from?
Hint: Say the word "Nilotic" slowly.
And the Cushitic supply the altitude adaptation. Not very hard to follow.
Apparently too hard for you to follow. The southern Cushitic people don't come from altitude so they couldn't supply the altitude adaption. They come from the Tanzanian Rift Valley at about 2000 feet.
probability ain't your friend wrote:
stayed forever wrote:They spread if the selection for them is rigorous, which it was.
How was the selection rigorous? Anyone can live comfortably at altitude.
No it does not spread like wildfire, even with selective breeding. The math is easy to figure out.
Gestating at altitude is more difficult. Are you supposing that all genes are inherited and expressed in identical fashion mathematically?
Lactase persistence reached 80% of a population pretty quickly for example.
It's all bs. Watch this. All of it.
Brad Wilkins wrote:
stayed forever wrote:And the Cushitic supply the altitude adaptation. Not very hard to follow.
Apparently too hard for you to follow. The southern Cushitic people don't come from altitude so they couldn't supply the altitude adaption. They come from the Tanzanian Rift Valley at about 2000 feet.
There you go assuming they were "pure" and arose in that area.
stayed forever wrote:
Lactase persistence reached 80% of a population pretty quickly for example.
80% from what? The Nilotes have been lactose tolerant for a long time.
herb j wrote:
stayed forever wrote:Lactase persistence reached 80% of a population pretty quickly for example.
80% from what? The Nilotes have been lactose tolerant for a long time.
80% of those of European origin.
"The Nilotes" are not actually ALL lactose tolerant.
However lactose tolerance apparently managed to spread almost entirely through an African population in about 3000 years. Wildfire in genetic evolutionary terms.
When your tribe adopts pastoralism and it's milk or nothing else, you select in a hurry.
Yeah, wildfire by evolutionary standards. The Kalenjin have been at altitude for only what, 500 years.
probability ain't your friend wrote:
Yeah, wildfire by evolutionary standards. The Kalenjin have been at altitude for only what, 500 years.
They met and mixed with the altitude adapted Cushites almost 3000 years ago.
nouse4aname wrote:
Henrik Larsen pretty much ruled out altitude being the determining factor in East African running dominance. He tested a group of sedentary Kenyan kids and compared their results to a group of sedentary Danish kids. No difference in aerobic capacity or performance.
Then he trained both groups for 12 weeks. They improved in a similar magnitude, suggesting that there was no difference in trainability between groups. There was also no difference in muscle fiber type between groups.
However, they did find a significant difference in running economy. The Kenyan boys had lower running economy when compared to the Danish boys, both before and after 12 weeks of training. This difference was attributed to the significantly lower mass of the shank in the Kenyan boys. It has been shown that for every 100g of extra mass on the lower limb, we have a 1% increase in cost of locomotion. So the lighter, thinner legs of the Kenyan boys reduced their cost of locomotion.
He basically concluded that the dominance of Kenyan runners was down to significantly lower running economy which was primarily due to their longer, thinner legs.
REFERENCE:
Larsen, H. (2003) Kenyan dominance in distance running. Comparative Biochemistry and Physiology Part A. 136; 161-170
What's interesting about the thin limb theory is that it suggests that dominant runners wouldn't come from altitude (unless they were newcomers), since thin limbs are an adaptation to extreme heat that tends to absent at high altitude.