Oh, Lord, so many things wrong with that it’s hard to know where to begin.
Let’s just say that the very first word, “presumably” has no basis in fact. One might argue that it was the weakest people who were easiest to catch. But, in fact, we know that whole clans or villages were sold by local chiefs and there was little, if any, selection going on.
There was no known eugenics program, and even if there was, it would have been tiny and very short lived.
The type of conditions that the slaves had to endure wouldn’t necessarily produce good runners, even if their genetic makeup had been altered by slavery.
#7 is Lammarkism.
This is typical nonsense produced by people who know little or nothing about either genetics or history.
ETA: If there is anything genetic going on at all, maybe it’s the fact that American blacks are multi-racial. European admixtures range anywhere from 5% to 60%, with the average being about 20%.
I don’t think it’s time to construct hypotheses like that until we have more concrete evidence that descendants of American slaves are more likely to be faster runners. The Olympic team is a pretty small sample, and there are plenty of opportunities for selection bias. Perhaps blacks are encouraged more to go into running than whites are for whatever reason. Perhaps whites are just as good at running but even better at something else. Or who knows what else.
Dude, if you want to refute anything I said, do so. This information is neither good nor new. If you think otherwise, the burden of proof is on you. I offered more of a refutation than your OP deserves. If you want to put forth a thesis, the burden of defending that thesis is on you.
I am skeptical of points 2, 3, and 4 for economic reasons. Many slaves were captured either in battle or by raiding parties operating in foreign lands. Either way would be very dangerous. Why would you let half of the people you risked your life to capture die before you sold them?
Likewise slave ship captains had to pay the traders large sums of money for the slaves, why let half of them die before you get a chance to sell them?
Alternative hypotheses that are more plausible to me include the possibility that most west indians are mixed race at some level, and africans have been generally too poor to adequately nourish their children to the level a world class athlete needs. Because west indian cultures prize sprinting more than most more of their young people give it a try, whereas african children are more likely to play soccer or not play sports at all.
When I first heard of these sort of studies, I thought that, while there is no evidence for this, that the increased incidence of high blood pressure et al. amongst african-americans could be caused by either the epigenetic effects of having ancestors exposed to the stresses of racism and classism, or the epigenetic effects of having ancestors exposed to the harsh working conditions of slavery in which they need to conserve as much water as possible.
Granting that you’re offering a hypothesis that’s compatible with Darwinian selection, my point was that we’re not to the point where we should feel a need to offer such hypotheses. You’re suggesting a mechanism for an effect, when we don’t even know what the effect is, or even if there really is an effect.
If you can show that there’s a specifically genetic component to the phenomenon you’re discussing, then it’s time to start wondering about mechanisms.
Testosterone makes one weaker against disease and parasites.
Suicide, killing slaves that try to kill the slavers, killing slaves for resisting too much & to terrorize the others. Then there’s the horrible conditions they were kept in. And these were people engaged in a horrific act; they had to dehumanize their victims, convince themselves that they weren’t worth any concern or empathy; I’d expect slavers to be irrationally determined to not care about the slaves.
Indeed, not only this, but specific West Indian cultures prize sprinting. Sprinting is a huge, huge deal in Jamaica; high school track meets are major sporting events. Usain Bolt atended a high school well known for its sports development program, was identified as a potential track start there, and was actually moved from cricket to sprinting by coaches who saw where his real talent lay. In another country he might not have had the development program in palce to identify and nurture his talents. He was then moved on to the University of Technology at Kingston, which is basically to sprinting what Duke is to college basketball; a center for studying and training sprinting at the highest levels of support and expertise. Champions train there and then go back to train more champions; if they had the inclination to do so they could probably have John Goodman running the hundred in 12 flat in a year. The Jamaican concentration on sprinting is much like the Canadian hockey system, has has predictably similar results.
Just to the north, sprinting is not high on the list of Cuban sports obsessions, and Cuba, not coincidentally, does not produce many sprinting stars (but does produce elite baseball players; does being descended from slaves help you get around on a fastball?) Yet Cuba must surely have many descendants of slaves.
I have no problem with the notion that certain groups are inherently more suited to some athletic endeavours and less suited to others. If we agree that genes affect the construction and operation of the body then it is hardly a huge jump to imagine a population carrying such genes would be over-represented.
If we went back a few hundred years to a time of greater population isolation and we were able to expose all the human race to the same environmental and cultural factors and then test for aptitude at certain activities, I can certainly imagine finding statistically significant differences.
Now…I think the picture is much more difficult and to be able to separate out the factors is a very difficult job and, to be honest, I’m not sure the answer would be very helpful. And, unfortunately, for every one of us who’d see it as an interesting academic exercise there are another couple who use the conclusions for nefarious ends.
And in any case, as populations intermingle far more I reckon we’ll all end up a rather fetching dusky brown and be a hotch-potch of various genetic ingredients to the point where even worrying about the questions will seem rather silly. Can’t come soon enough if you ask me.
This to me is the heart of the matter. What I think many people miss in this sort of discussion is the wholly artificial (in the sense of not occurring naturally in the environment) intervention of culture, training and resources. Black people who descended from slaves are not more likely to be good sprinters. People who come from a culture where sprinting is prized and has resources ascribed to it and have proper coaching and expertise to draw on are more likely to be good sprinters.
If the documentary from the OP was correct, then you could just as easily come to the conclusion that being a descendant of Europeans seeking a new life in Canada and being the descendant of Russian peasants offers some genetic or natural predisposition to be good at hockey. I doubt anyone would reasonably believe that because we know Canada and Russia produce a lot of hockey players because both nations have a strong hockey tradition and strong development systems to give people the chance to become great players.
What I think people fail to recognize as well is that no amount of genetics or natural ability will be worth more than training and practice. If the average person’s ability at a skill (say running fast) is x and the person with the good genes is y, then they might look like this on a left to right scale of skill (left is low, right is high):
X – Y
But add in training and expertise and resources and culture and so on, to the degree that an Olympic-level athlete gets, and the difference between the two becomes something more like this:
X ---------------------------------------------------------------- Y
Y ------------------------------------------------------------ X
That is to say, training and so on means more than any natural ability by orders of magnitude that eclipse natural ability from the equation. It doesn’t matter how naturally skilled you are, to be elite, or even just very good, you need to practice, practice, practice.
One common - and, to me, convincing - explanation is simply due to the inequality of society. In the US, African Americans are over-represented in sporting endeavours because academic opportunities can be harder to come by for them. It’s nothing to do with genetics, or ability; it’s all to do with opportunities or the lack thereof.