What they didn't tell you about NEANDERTHAL admixture

Everyone who has access to the internet and has an interest in genetics knows that Eurasians have denisovan and neanderthal admixture.
This is something we all pretty much know, and take at face value, without ever doubting. Experts say so, therefore it must be true!
What we often don’t realize is that experts own opinions change over time, one decade they say one thing - another decade when their technology changes they say something else. Another thing we don’t realize is that experts are humans just like us. They have biases, they have their own agendas, they make mistakes.
At the end of the day, just because a Harvard study concluded something, does not mean that this conclusion can not be scrutinized if it has obvious flaws.
I see some very obvious logical flaws with statements about neanderthal or denisovan admixture in eurasians, or any archaic admixtures in any modern human population for that matter. In this video I will discuss them.

Admixtools and QPADM can supposedly detect neanderthal admixture in Europeans and East Asians, but I am highly skeptical of the validity of such models. These trends could and likely do simply reflect genetic drift in Eurasians that isn’t found in Sub Saharan Africans. QPADM models can be manipulated to display just about anything and need to be taken with a grain of salt.
Additionally, having worked with neanderthal DNA files in the past, I noticed a very peculiar trend that neanderthals resemble Sub Saharan Africans, not Eurasians. On every GEDmatch calculator and PCA based calculator they score Sub Saharan Africans. On my own ethnicity calculator they score identical to Sub Saharan Africans.
Since we do not have a Eurasian sample without this supposed neanderthal admixture to compare the rest of eurasians to, all these QPADM models showing neanderthal and denisovan admixture become rather irrelevant - all they do is show that Eurasians have diverged from Sub Saharan Africans, not that we have neanderthal or denisovan admixture.
The most robust way to establish that some sort of admixture happened is by DNA segment size. That’s how 23andMe establishes the ancestry timeline, or when your ancestors from a certain ethnicity became a part of your family tree. Since DNA is inherited in chunks, the larger the chunks the more recent this admixture is. You could be 25% french for example, but if those 25% are all from one granddad - then you would have only a couple very large chunks of french DNA in your genome. Whereas if your 25% french ancestry was from a bunch of ancestors from 10 centuries ago who mixed a long time ago, your french chunks would be small and more numerous.
Here’s what I’m getting at though. The chunks of neanderthal admixture we would have after 40 thousand years of mixing would be so small that it is impossible to establish whether it is the result of admixture or genetic drift.

The final nail in the coffin is the shortage of high quality neanderthal DNA samples. We can not build an allele frequency database for them like we can for modern populations, we can not study them the way we can study modern human groups.
What this means in the context of the Q.P.A.D.M. models mentioned earlier, is that an affinity to these low quality neanderthal samples such as the female skeleton from vindija does not imply an affinity to neanderthals as a whole, but rather implies a deviation from Sub Saharan Africans used as outgroup in the Q.P.A.D.M. model

[ytxdjld]

The First Eurasians analyzed as Bachi Kiro, OASe Tianyuan Man and have much larger Neanderthal DNA fragments which indicates that there was mixing between the Neanderthals and the Eurasians of the Upper Paleolithic.

[ytxdjld]

Bachi Kiro has Neanderthal ancestry recently 6 to 7 generations ago, they are considered anatomically modern humans or Eurasians, their lineages became extinct, but their sister lineages survived, such as UST Ishim Man and Tianyuan Man who left traces in ancient and modern Asians.

[Kabylevrill]

greetings andrei great video! it would be intresting to see you do guanche berber samples would love to see them

[NeanderthalRobust]

Northern Europeans were predicted to have some form of Amerindian ancestry in early calculators. Turns out it was shared ancestry (ANE) and hardly any European population (including European Americans that interacted with Native Americans for centuries) have Amerindian admixture. This is because of foreign diseases killing the small Indigenous population in excessive amounts which prevented them from having a successive and more populous generation. It would not be shocking if the same was said for Neanderthals or any archaic species.

[nataliak]

You are a genius, Andrei, and no need to hide your own voice. Go, Owl!

[Claqueur]

What agenda should these scientists have? Biologists all over the world have conducted independent research on this and come to the same conclusions.

[Kanasubigi]

But if Neanderthals and Homo sapiens didn’t mix then where did they go? They must have mixed at least a bit isn’t that logical?

[richern]

Building the House from the Roof down....First find the Common Ancestors DNA and then build the house upwards...

[richern]

What happened to the Replacement of Late Neanderthal Y and MtDNA Haplogroups with Early Modern Humans theory ? Or did the Early Neanderthals have the same Y and MtDNA Haplogroups ? Mmm...

[Chociewitka]

it has to have occured as we have confirmed hybrids in ancient samples - the question is more, if it has survived until today, and it must have if we have specific non-homo-sapiens derived genes at certain locations in some modern humans?

[MulletMonologues]

Good to know the truth from independent researchers like Andrei DNA versus from liars like Harvard

[ralfor]

Neanderthals and their depoction and the depictions snd studies of archaic genomes is incredibly political unfortunately. I thin vandraminis book them and us is also worth looking into if you already havent done so.

[chrono]

Andrei from Ukraine really believes he's smarter than Harverd

[phanomtaxskibididoodoo]

Why on earth are you using a Computer voice over?

[jahiemsterling]

I want to invite you to my private discord good work