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Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

sciencemag.org

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Re: Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

#91

Post by interestica »

Izkata wrote: post #39
wincy wrote: post #36

Earlier quoted context omitted.

I think it’s that all the worlds were seeded by some sort of progenitor race millions of years ago. Also they can interbreed I believe.

For Star Trek, in-universe this happened at least twice. The relevant episodes are TOS 2x22 Return to Tomorrow [0] and TNG 6x20 The Chase [1]. VOY 3x23 Distant Origin [2] also in-universe establishes convergent evolution is very likely to create humanoids (makes no reference to the other two episodes, as far as I remember, but it's kinda wishy-washy in that it could be highly likely because of the two progenitor spec…

Thanks for this. Definitely curious. (Your comment is so much better than what one could have quickly searched).

Sometimes real constraints (eg costuming/budgets/etc) can result in really clever explanations that strengthen the storytelling/worldbuilding.

Re: Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

#92

Post by nobody9999 »

interestica wrote: post #90
nobody9999 wrote: post #87

Earlier quoted context omitted.

>I always wondered if there could be some sort of in-world explanation as to why all the aliens in star trek/wars are so ...humanoid. I'd say that for most Sci-Fi Movies/TV there's a couple of reasons: 1. Non-humanoids are less relatable than humanoids; 2. Budgetary restrictions and the relative immaturity of CGI holds us back from creating fairly realistic and relatable alien species.

Yes, that's the real reasons. But by 'in-world' I meant something that could be explained within the story/world-building to justify/explain it away.

I know. I just thought I'd throw that out there since no one else did.

Re: Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

#93

Post by enkid »

Ygg2 wrote: post #80
enkid wrote: post #69

Earlier quoted context omitted.

If they are remanants in people's DNA, they did become common ancestors, no? Everyone's family tree collapses to the same individuals at 5500 BC, after the other humans went extinct.(1) That means we are all descended from non Homo Sapiens humans. What I'm trying to say is that they were not "purged," we are their descendants. We got most of our genetic material from the Homo Sapiens side, but there is continuity wit…

Common ancestors are in all humans IIRC. While say Neanderthal DNA is only in subset of populations.

You don't necessarily have any DNA from any particular ancestor, but they would be your ancestor. This is explained in the article I linked. That means that if everybody's ancestors converged in 5500 BC, and at least one person had a Neanderthal as their ancestor, everyone has a Neanderthal ancestor.

Re: Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

#94

Post by thaumasiotes »

scarmig wrote: post #83
thaumasiotes wrote: post #37

Earlier quoted context omitted.

Ring species are so called because their breeding relationships form a cycle. You're only describing a chain. You would have described a ring species if you could mate with your dog. (Also note that while it's perfectly possible to walk up from humans to an ancestral slime creature, and then back down to dogs, most of the steps along that path will be shared between humans and dogs, like a Y with a very, very long le…

The point about the most recent common ancestor is well taken, but, at least according to my layman's level understanding of ring species, the two ends of the "ring" aren't expected to interbreed. Wikipedia supports that definition (and if it's wrong, should be updated by someone more knowledgeable than myself).

You seem to be right about the idea of "ring species". Papers from the past several decades all introduce the concept the same way.

Re: Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

#95

Post by scarmig »

thaumasiotes wrote: post #94
scarmig wrote: post #83

Earlier quoted context omitted.

The point about the most recent common ancestor is well taken, but, at least according to my layman's level understanding of ring species, the two ends of the "ring" aren't expected to interbreed. Wikipedia supports that definition (and if it's wrong, should be updated by someone more knowledgeable than myself).

You seem to be right about the idea of "ring species". Papers from the past several decades all introduce the concept the same way.

Yeah, though I wouldn't be surprised if your suggested "continuous" ring species exists somewhere, with gene flow possible from both sides at every point but not from one side of the ring to the other (even if brought into the same geographic proximity).

In principle you even could have some kind of genetic helix, where one end of the ring species not only meets but overlaps with the other, perhaps going so far as to do a full wraparound a number of times. But probably the two ends of the ring would occupy too similar an ecological niche (even with all the genetic divergence) to allow for much time of overlap.

Re: Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

#96

Post by Izkata »

Izkata wrote: post #79
CobaltFire wrote: post #77

Earlier quoted context omitted.

I know some people don't like Enterprise, but it IS in-universe, so lets not forget ENT 1x05 Unexpected [0]. I kid; I know you said "at least". [0] https://memory-alpha.fandom.com/wiki/Unexpected_(episode)

Oh, I was referring to progenitor seeding specifically. In terms of interbreeding, there's a few more prominent ones: Spock, B'Elanna Torres, and Alexander Rozhenko and B'Elanna's daughter (who are respectively 3/4 human and 1/4 human, showing there likely isn't an infertility problem like with mules [0]). (Though I admit that the ENT example was certainly unique in the differing biologies) [0] https://en.wikipedia.o…

Dangit I changed the order of "Alexander Rozhenko" and "B'Elanna's daughter" to make it clear they're not related, and forgot to switch the 3/4 and 1/4. Alexander is 1/4 human.

Re: Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

#97

Post by mytailorisrich »

enkid wrote: post #67
mytailorisrich wrote: post #49

Earlier quoted context omitted.

Even as the single human species we used to be spread into isolated groups, that's why different populations have specificities (e.g. skin colour, but also other adaptations). Now that we have such a huge and interconnected population diversity will fade and adaptation will slow.

I don't think that genetic diversity will necessarily slow under those conditions. Genetic differences between people are already dominated by individual genetic differences over group genetic differences. Our diversity is more about us as individuals than as a collection of groups. Why, then, would the mixing of groups decrease diversity? I would think it would increase it.

For example, Tibetan people have developed a genetic adaptation to high altitude. This can only have happened because of the relative isolation of that specific population. Now that we are constantly mixing and have technology to fix everything such adaptations are much more unlikely to arise or even to be kept.

All in all, the global human population will become more homogeneous and less diverse.

Re: Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

#98

Post by enkid »

mytailorisrich wrote: post #97
enkid wrote: post #67

Earlier quoted context omitted.

I don't think that genetic diversity will necessarily slow under those conditions. Genetic differences between people are already dominated by individual genetic differences over group genetic differences. Our diversity is more about us as individuals than as a collection of groups. Why, then, would the mixing of groups decrease diversity? I would think it would increase it.

For example, Tibetan people have developed a genetic adaptation to high altitude. This can only have happened because of the relative isolation of that specific population. Now that we are constantly mixing and have technology to fix everything such adaptations are much more unlikely to arise or even to be kept. All in all, the global human population will become more homogeneous and less diverse.

People being less adapted to specific environments is not the same thing as being less diverse.

Re: Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

#99

Post by _opc6 »

mytailorisrich wrote: post #85
_opc6 wrote: post #82

Earlier quoted context omitted.

Speciation is an ongoing process and it's happening right now in the human population. https://news.sky.com/story/human-microevolution-sees-more-pe...

Evolution may of course be ongoing but not speciation in the sense of splitting into different species as we are now constantly mixing. Speciation processes may return once we start colonising other planets as it is highly possible that physical contacts between populations will stop.

Whether or not all populations on Earth are mixing enough to prevent speciation remains to be seen. But the process begins with the kind of mutations documented in the article.

Re: Mysterious ‘super-archaic’ populations had multiple trysts with human ancestors

#100

Post by adenozine »

lebuffon wrote: post #74
gen220 wrote: post #35

Earlier quoted context omitted.

I encourage you to explore the early history of the pre-Roman Empire peoples. These were largely mythologies that the romans retroactively constructed for themselves (i.e. they had the opportunity to omit the raping and kidnapping in retellings, but chose not to). It’s full of “and then tribe X invaded and the land of Y, took their women and enslaved their men”. Back and forth for centuries. This behavior was cyclica…

"pre-Roman Empire peoples" Do you mean the Bible? "Only in the cities of these peoples that the LORD your God is giving you as an inheritance, you shall not leave alive anything that breathes. But you shall utterly destroy them, the Hittite and the Amorite, the Canaanite and the Perizzite, the Hivite and the Jebusite, as the LORD your God has commanded you,...? Deut. 20:16..

That's an interesting scripture for this situation! Very insightful.

I was thinking actually quite a bit earlier than a lot of the Hebrew historical times, like species that were more apelike.

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