This is kind of the best-case fantasy of what happened to introduce that DNA so let's just hope it's true for now.
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Where do Neanderthal women be??
How do we know it wasn't the other way around?
a paper came out recently. it's also possible that male humans and female neanderthals made non viable babies.
There is a few different potential reasons as well as sexual preference.
Genetic incompatibility - the interspecific cross could only occur one way.
Genetic bottlenecks in the neandertal lineage. A high inbred coefficient could have decreased the neandertal females overall fertility (high deleterious alleles load). This could also cause a rapid reduction in the percentage of neandertal DNA in a mixed population.
Maternal behavior - Neandertals females might not have cared for hybrid offspring appropriately. This could be for anything from milk production requirements to differences in physiological developmental rates.
I think the idea of there being health issues in certain types of mixed families is super interesting because that almost certainly would have been noticed and lead to certain cultural practices or taboos within both species' societies.
If I had to guess the successful crosses were potentially much healthier than either parent line. Heterosis (hybrid vigor) would likely be pretty extreme in genetic lines that has been isolated by 300,000+ years of time. Of course the degree of fertility was likely lowered due to genetic distance. Once the initial cross was made however, back-crossing to either species by the hybrid would likely be much easier.
Many of those ancient stories about individuals with super strength and size etc could have likely been based upon these crosses.
The evidence is showing neadertals never truly died out. Their smaller population bred back into the modern humans who came later.
Keep in mind heterosis isn't always the result of hybridization and even then the magnitude of isolation doesn't always positively correlate. Outbreeding depression can also be the result, increasingly so when two groups are more genetically distant or when one group is already subject to heavy inbreeding depression, as the neanderthals were thought to be.
Two ways.
First, sex chromosomes. In mammals, sex is determined by the sex chromosomes - males have XY, females XX. If interbreeding was equal between the sexes of both species, this would be reflected in the frequency of neanderthal genes on each chromosome in the current human population, but it's more heavily skewed toward the Y chromosome than we'd expect if equal pairing was true. This suggests a higher proportion of successful male neanderthal/female human offspring.
Second, mitochondrial DNA. While genomic DNA in a sexually-reproducing species is a mix between the parents, in most mammals the inherited mitochondrial DNA (mtDNA) is purely maternal. This is because only the egg's mitochondria typically survive, though on rare occasion paternal mitochondria are also passed on. There is no known existent neanderthal mtDNA in the human population. This suggests either female neanderthal/male human crosses didn't happen much and/or didn't often produce offspring capable of further reproduction.
Of course, there are many other explanations for all of these. These are just amongst the simplest possible options, and in population genetics, it's not uncommon that the simplest answers are frequently correct.
So, how likely is it that neanderthals and humans just lived in tribes together, and neanderthals just eventually died off within human tribes?
I bet it at least ended that way.
They died out during the last ice age when one of the big differences from previous ones they survived was the presence of homo sapiens.
I'm guessing it was from a combination of lack of space, raids, and integration (willing or not).
We (who carry it) have a small amount of Neanderthal DNA, but it's not the same DNA for all of us, it's pretty diverse, so cross breeding events between us weren't limited to just a few times.
They were probably just genocided like many other minorities in history. And since Homo Sapiens succeeded, everyone promotes how superior we are.
BTW, our genetics apparently just merged, but my theory is probably also true.
Neanderthals were more peaceful than Homo Sapiens.
We don't actually know that. Homo Sapiens is on the whole a peaceful species, but we have a few assholes that like to kill and subjugate.
Just because our assholes outlived their assholes, doesn't mean that they were any less assholes on average than we are/were
hunter gatherers vs agriculturers say otherways. Mass of graves and the murdering entire family lines and clans and villages go back as far as humankind goes back. Homo sapiens are no different than any other animal—opportunistic killers like cows and horses are.
Yep, the relative lack of heterogeneity in the Y-chromosome compared to mtDNA is somewhat testament to that too, but those mass grave sites are late stone age. Neanderthals predate those sites by a large margin, so it'd be hard to say that they didn't necessarily follow the same brutal history against their own kin
Context?
Clan of the cave bear vibes
Did they have bigger dicks or something?
Pretty sure they actually did
You're allowed to say dick on the internet
What's with that dicks?
Check out Beforeigners - there is some prehistoric romance atuff there:
https://www.imdb.com/title/tt8332130/
(and the series are generally interesting)




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