After 32 generations (~800 years) you have more genealogical ancestors than there are base pairs in human DNA. There literally isn’t enough resolution to store a “record” of each of your ancestors, even if you inherited exactly 1 base pair from each ancestor.
Additional complications make it an even shorter timeline. After about 8 generations, you share no more DNA with your ancestors than you do with a random stranger.
Politically this should be more well known. Of course, racists and fascists rely on “blood quantum” arguments to justify racial or ethnic oppression. But they don’t invent this idea of strict genetic identity. It’s latent in the population.
Leftists should more frequently call out genetic tests like 23andMe as inherently racist because it’s based in race science nonsense. It may not be as obvious as Nazis invoking aryan genes or whatever; but it’s still just as incorrect when your aunt at Thanksgiving talks about how she discovered she’s 2% Choctaw or whatever
The keyword is each. You still have DNA from many of them. Plus DNA based ancestry works with key genes. A male has his father's Y chromosome, who has his father's Y chromosome, who has his father's Y chromosome and so on. The same goes for mitochondrial DNA through the maternal line. There are mutations of course, but those actually allow you to paint an (imperfect) timeline and create groupings (haplogroups). Men from Europe have more similar Y chromosomes to each other than to men from elsewhere.
Obviously none of that justifies racial or ethnic oppression nor indicates any significant differences between peoples, but it does allow for those trivial (as in, interesting bits of information that aren't all too useful otherwise) but imperfect groupings.
I don't know how the exact percentages are determined and I'm sure there is something closer to race science bullshit in there, but it's mixed with actual science. It's pretty simple to see for example that my mitochondrial DNA aligns more with people from Iberia while my Y chromosome is much more like men from England. Thus I am half Portuguese half English(-descended American). But it means absolutely nothing other indicating who my parents are. That of course tells you nothing about my intellectual or physical abilities or any predispositions despite what fascists claim.
but those actually allow you to paint an (imperfect) timeline and create groupings (haplogroups)
I don't know how the exact percentages are determined
That's where most population genetics scientists get angry at 23andme, not necesarily because their statistical methods for genetic admixture are wrong but how average people will (expectedly) misunderstand the results. Let alone how they then will act with the new premise of
"I'm part moroccan, part finnish, part italian, part aztec and part korean"This is correct. I think part of the issue comes from assuming that because a few genes can be tracked as population markets means there is more variability between people of different backgrounds than people of the same background - when in reality having the same background only accounts for 15 percent of genetic difference, with the rest being individual variability.
Well said. Genetic information comes from many sources of descent and can be used to pinpoint lineage. Plus there's even talk of epigentic profiles being inherited (at least parent-child), which could be an extra coordinate.
Aren't all inhabitants of the British isles descended from Mil king of Galicia? So there is a better than 50/50 chance your y chromosome would also look Iberian.
Don't discount inbreeding tho. Not just cousins or whatever, but villages and groups of villages. Peoplehave gotten increasingly mobile over time of course but the reason there are groups of folks that look a bit different from one another is that we split off for a little while and became semi-isolated.
PS this isn't race theory, just genetics and a recognition of human variation. We are all modern humans and overall the same, our differences are very minor. One example would be lactose tolerance (which is the less common thing for humans to have than lactose intolerance) which has popped up a few times in human genetic history but did not spread out over the whole population in a couple thousand years.
Yeah, the post says at 32 generations (800 years) there's more ancestors than base pairs, but at 37 generations, there's more ancestors than humans that have ever existed.
37 generations doesn't take us back to pre-human times, does it? Or is that not what you're saying?
No it's like 900 years. So the fact that 900 years back, you should have over 100 billion ancestors indicates a lot of inbreeding. And to be clear, not necessarily familial inbreeding (though ofc that too), but just like, being distantly related too.
Just you wait until some wacko invents homeopathic genetics to refute this. The blood has memory!
Oh yeah? Explain that to the heirloom jar of “dna” (similar to a sourdough starter) passed down to me that I literally carry everywhere
racists and fascists rely on “blood quantum” arguments
I have no idea what that is and I am too afraid to ask.
In North America, a certain percentage of your ethnicity must be Native American in order to qualify for recognition by the government to receive tribal benefits. I think it's a minimum of 1/12th. in the US (not 100% positive on the exact number). This is called the "blood quantum."
If you don't meet the minimum, regardless of how or where you were raised, or what you look like, or what languages you speak, you are automatically disqualified from stuff like scholarships, reparations, and official membership to a federally recognized tribe. This was put in place in the early 1900s by white people with no discussion about how Native Americans establish heritage or tribal membership.
A lot of racism in the US still lingers around this concept where a person is or isn't part of an ethnicity based on their blood quantum, rather than their lived experiences. Someone who is 1/4th. black, for example, may have their concerns dismissed because "they're not really black." That is until it becomes convenient for the racist to go by the "one drop rule," which is when a person has any non-white heritage, they are no longer considered white (even if it's something like 1/100th. black).
I think it's a minimum of 1/12th.
Depends on the tribe/nation, which is the insidious part of blood quantum. It's a genocidal tool developed by settlers but implemented and enforced by comprador governments themselves.
Someone who is 1/4th. black, for example, may have their concerns dismissed because "they're not really black." That is until it becomes convenient for the racist to go by the "one drop rule," which is when a person has any non-white heritage, they are no longer considered white (even if it's something like 1/100th. black)
Yea and the thing is, by 1/4 and 1/100 here, the implied meaning is genealogy ie one’s family tree, which from the posted video is absolutely different from one’s genetics.
From each grandparent, a child receives anywhere between zero and 1/2 of their genes. The only constraint is that the sum of contributions from both grandparents (on one side) is 1/2. That means it is possible to have almost no actual genetic relation with grandma, while bearing a striking similarity to grandpa due to his genes contributing 50% of the child’s DNA.
Blood quantum is on-its-face wrong. We don’t receive 1/4 of each grandparent’s DNA. That is only an average. And of course this doesn’t address the glaring issue of identifying race with genetics.
Really highlights just how ass-backwards Richard Dawkins is when he suggests DNA is the begging and the end, the only thing that actually matters
Dawkins is a piece of shit for a number of reasons, but where did he ever say anything like that?
Perhaps I'm misremembering, but I'm pretty sure he describes everything about life as just a means for DNA to propagate itself. As if DNA isn't merely a component in a larger, more complex and complicated system, but as the reason for the whole thing.
You're not misremembering because those were major misconceptions about what he was saying, especially in the premise of the book that made him famous, The Selfish Gene. But that book as well as his other ones on evolution, genetics, and biology are accurate, with Selfish Gene just being a popular-accessible explanation of the scientific consensus on the role of genes in evolutionary biology. It was misconstrued, often intentionally and said to be this nihilistic justification for human selfishness, which it's not, and I think that's what you're remembering. It's one of those instances where someone who may be an asshole and totally worthy of criticism gets criticized for mostly the wrong reasons, and those wrong reasons are what end up getting solidified in memory incorrectly as why they're an asshole.
Replicating molecules (like DNA) replicating and propagating themselves is the "reason" for the whole thing in terms of how biology at the molecular level works. It's not an answer to a "why" question, but a description of what's really going on at scales we aren't used to thinking about or readily able to see. But neither Dawkins or any other evolutionary biologist I'm aware of ever implied that DNA is all that "matters" or that or that other systems aren't at play in reality. Just like the fact that "all the matter we see, including life, is composed of interacting atoms" does not negate the presence of society or human emotion, neither does the genetic description for the foundation of life and how it evolves.
But all of that is aside from Dawkins' Islamophobia, misogyny, deep misunderstanding of systemic racism (i.e., just racism), his flippant disregard of (CW) SA victims with the justification that he was one himself and therefore had the right to extrapolate everyone else, his creepy views on human sexuality, etc. In other words, Dawkins is a shit person and absolutely should be called on all the disgusting nonsense he's said, but let's call him on what he actually got wrong and not perpetuate misconceptions about all the stuff he got totally right regarding evolution and biology, which ultimately just carries water for the chuds and creationists.
Mate the chuds and creationists are uniquely your country's fucking problem
You've constructed a straw man from this:
he describes everything about life as just a means for DNA to propagate itself. As if DNA isn't merely a component in a larger, more complex and complicated system, but as the reason for the whole thing.
It's been decades since I read it but the selfish gene was absolutely full of this genre supremacist shit and his evo-psych trash clearly infects all his views
Mate the chuds and creationists are uniquely your country's fucking problem
White supremacist right-wingers are uniquely a US problem? I'd agree they're uniquely powerful in the US but that's a major reason why the US is "uniquely" the world's problem. What a strange take to read here, that chuds are only something USians need to be concerned about.
You've constructed a straw man from this
That makes no sense. I'm not attacking anything, so there is no strawman to create. You just quoted someone else who said something that Dawkins himself never said, so it seems pretty obvious where the strawman is and who is creating it.
It's been decades since I read it but the selfish gene was absolutely full of this genre supremacist shit
"Gene supremacist"? lol, what even is that? Understanding how genes replicate is not "gene supremacist shit," it's scientific consensus. "The matter of the world around us is made up of atoms and their interactions? That's just atomic supremacist shit." These sentences have no meaning.
his evo-psych trash clearly infects all his views
To the extent he believes in evo-psych, I'm sure it does effect his views, some of which I explicitly addressed. That doesn't invalidate the real science, which despite being a terrible person, he has also done and made contributions to. He's hardly the only scientist who had a lot of shit views on other topics, that's even the majority. Plenty of them think their expertise on one topic makes them an authority on others and they are wrong, and Dawkins is one of these as well. That doesn't make him wrong about how genes work or the broader biology and it certainly doesn't make the premise of The Selfish Gene wrong.
Not an expert but
In the first place, mitochondrial dna are shared among many people, for the basic fact that it is passed matrilineally. This allows us to prove the existence of the so-called Mitochondrial Eve, to whom all humans alive today are related.
Second, the mitochondrial dna encodes basically the production of ATP. Not genes that would be used to express any apparent difference between people.
Third, the number of base pairs in mitochondrial dna is very small, tens of thousands, compared to the 3.1 billion base pairs in nuclear dna.
Most people wouldn't consider 800 years to be their ancestry. 3 generations is the typical.
800 years is just the hard cap, the theoretical maximum. In reality, not all 3 billion base pairs are relevant to distinguishing humans from each other. Much of the genome is just basic biology shit, which is why the human genome overlaps 70% with bananas, 96% with chimpanzees, etc.
This 800-year rule also ignores the fact that there were not 4 billion people on earth in 1250 AD. There is a lot of… ahem… crossover within our lineage.
The point is that the way many people think about identity is rooted in a wrong understanding of genetics. The whole point of these genetic tests is to discover a supposed “true” identity that is ostensibly encoded in one’s DNA. Closely related with this belief is a strictly biological view of race and ethnicity.
that's totally false. people feel all kinds of ways about things done hundreds, even thousands of years ago.
lots of people will tell you about their "line" being "traced" back to such n such. most prominently all royalty everywhere but lots of normal people have stories.
this feels pretty culturally disconnected/nuclear-family-brained tbh
I mean, same, but I wouldn't want to project that onto others. Feels like conflating these new age physiognomy peddlers' bullshit with actual connection to place and people
Imma hold your feet to the fire now. Give us your complete, thorough analysis, now.
I found a YouTube link in your post. Here are links to the same video on alternative frontends that protect your privacy:
