Interspecies fun (and benefits)

November 8, 2006 1:13 PM

Neanderthal Lovin’! New research from evolutionary scientist Bruce Lahn suggests that humans and the now extinct Neanderthal species mixed, and humans snatched up a valuable brain gene in the process. (The gene, MCPH1, and Lahn, discussed last year on MeFi) This comes on the tails of yet another new study providing morphological evidence that there was nontrivial interbreeding between humans and Neanderthals in Eurasia, despite the fact that Neanderthals may have been genetically closer to chimps than humans. Contrary to popular imagination, though, the Neanderthal species had bigger brains and sophisticated intellects, at least roughly on par with that of human beings. The gene regulates brain size during development, but its exact utility to humans is still unknown (and controversial). The origin of this gene and the question of Neanderthal mixing will soon be answered more definitively by the, just launched, 2 year project to map the Neanderthal genome, headed by Svante Pääbo (profiled in recent Smithsonian and Wired articles). Pääbo calls Lahn’s study "the most compelling case to date for a genetic contribution of Neandertals to modern humans."
posted by Jason Malloy (26 comments total)

The paper is available free here. Anthropologist John Hawks provides some Q&A here and here.
posted by Jason Malloy at 1:15 PM on November 8, 2006

Great post Jason Malloy.

So all of us have a Neandrathal in the wood pile. There you have it.
posted by three blind mice at 1:27 PM on November 8, 2006

All of my interbreeding is nontrivial.

"Hey baby... you know what they say about a species' cranial capacity..."
posted by XMLicious at 1:30 PM on November 8, 2006

I wonder how often this evolutionary device is employed within a group of species. A few zoos have ended up with ligers, and there's mules. I've always held the notion internally that evolution was a sort of branching mechanism, and I find it interesting that it might not be the case.

I guess it's time to grab a Barry White CD and get to know a few pidgeons cause I'd be swell if my decendents could fly!
posted by The Power Nap at 2:09 PM on November 8, 2006

This is really cool.

At the same time, while I hate to say it, this has very distressing racial implications. Hopefully they'll sort out what the phenotypical effect of these genes is before people start whipping them out as the definition of white power.

Then again, it'll at least be amusing to find someone say non-european race X is less intelligent because they aren't neanderthals.
posted by Alex404 at 2:14 PM on November 8, 2006

I'm never going to get used to spelling Neandertal without the "h". (I pronounce it without the "h", though.) *sigh*

Hawks's 2nd Q&A covers some technical points about genetics but is for the main part very readable. And he answers The Power Nap's question.
posted by dhartung at 2:20 PM on November 8, 2006

The Power Nap - "...get to know a few pidgeons..."

Is that you, Nikola Tesla...?
posted by porpoise at 2:36 PM on November 8, 2006

Cool. But I hope this doesn't lead to some massivel psycho rationalization by Dr Satoshi Kanazawa.
posted by DenOfSizer at 3:59 PM on November 8, 2006

Fine, if no one else will:

I'd hit it.
posted by Bookhouse at 4:12 PM on November 8, 2006

They gave us brain capacity, we gave them herpes.
posted by graventy at 4:40 PM on November 8, 2006

I think this is what Rick Santorum was warning us about! Slippery slope folks. First you let people develop stone tools, you let females weave grass skirts, next thing folks are bangin' monkeys!
posted by Pollomacho at 5:05 PM on November 8, 2006

I'm never going to get used to spelling Neandertal without the "h". (I pronounce it without the "h", though.) *sigh*

I'm never going to spell or pronounce Neanderthal without the h. Why on earth would you bother adapting to German spelling changes that took effect after we borrowed the word? Is there a Neandertal Action Committee that will get mad at you?
posted by languagehat at 5:13 PM on November 8, 2006 [1 favorite]

We're talking about Homo neanderthalensis here so why would you change?
posted by Pollomacho at 5:37 PM on November 8, 2006

I always thought it was highly unlikely that if we bothered to kill them off, we wouldn't have raped them while we were at it.

I mean, it isn't like human men at war are known for avoiding rape while pillaging, nor do they avoid taking female slaves. If interbreeding was possible, it was going to happen-- and I would have been completely surprised if this left modern humans without any Neanderthal genes if there'd been any contact between the groups at all.

If there was nonwarlike contact like trading, mating would have been there, too, clearly.

And just think about how you could really enrage your parents with such a mate choice!
posted by Maias at 6:26 PM on November 8, 2006

Hotlegs!
posted by tellurian at 6:43 PM on November 8, 2006

The New York Times says that there are going to be two more studies in the next few weeks supporting human interbreeding with extinct hominid species (probably including the one Hawks mentions with him and Gregory Cochran). This paper estimates that 5% of modern human genes were acquired this way; mating with our cousin species in both Europe and Africa.

This may have been an important process throughout human evolution. A genetic study earlier this year also suggested that. . .

Our human ancestors were still interbreeding with their chimp cousins long after first splitting from the chimpanzee lineage. . . Early humans and chimps may even have hybridised completely before diverging a second time. If so, some of the earliest fossils of proto-humans might represent an abortive first attempt to diverge from chimps, rather than being our direct ancestors.

posted by Jason Malloy at 6:56 PM on November 8, 2006

Hotlegs!
posted by tellurian at 10:43 AM ACST on November 9

I mean, jeez, with go-go boots like those how could early homo sapien males resist?
posted by Pollomacho at 7:05 PM on November 8, 2006

I haven't read all the links, but the "genetically closer to chimps" one caught my eye. Thats just, um, stupid. Seriously. There is no measure - genetic, physiological, technological, cultural - on which Neanderthals are closer to chimps than humans. The very fact that there is disagreement still on whether they are best classified as Homo neanderthalensis or as Homo sapiens neanderthalensis is pretty much all you need to know: by any reasonable definition, these critters were human.

There are many models of Neanderthal:Modern interaction. To my knowledge, there isn't any empirical evidence of hostile interaction between the two groups. In places like the Levant the species co-occur over tens of thousands of years. In others, there appears to be replacement. Although the evidence for inter-breeding is slight, it is still stronger than the evidence for violent exclusion. Competitive exclusion, perhaps. Niche specialization, probable. War? Sorry, need another metaphor.

In fact, a lot of these studies show an all too common bias in archaeology: European exceptionalism. Neanderthals are really an unusually distinct flavour of archaic homo sapiens, limited in their distribution to the Levant and western Eurasia. Other archaic variants existed in, say, southern Africa, and there is emerging evidence that is where many of the key innovations in human H. s. to H.s. sapiens) adaptation occurred. In the global sense, Europe is a backwater, a backwash of human evolution. If this gene is as important as claimed (and I am no expert) it will need to be shown it arose in Neanderthals and did not arise elsewhere, say in archaic H.s. in Africa, and then pass into global archaic taxa, and thence into H.s.s. The PNAS article linked, for example, allows about a million years for this to happen. That degree of temporal imprecision captures almost all events of interest in the later evolution of genus Homo. To claim that it happened from H.s.n to H.s.s seems no more likely, and (based on the relative sophistication of the archaeological record of South Africa ca. 100,000 years ago, compared to neanderthal hyper-conservatism) actually less likely than that the transfer happened elsewhere. If there is a trend in human evolution, it seems to be innovation happens in Africa, and moves out of Africa, again and again.

so suck it eurocentric whiteys

And, good set of links, thanks.
posted by Rumple at 7:12 PM on November 8, 2006

Neanderthals may have been more talented in certain ways than the average Homo Sapien (of the day), but they is UGLY. Even today, beauty trumps brains. Neanderthals died out because even the Neanderthals prefered screwing the Homo Spaiens Sapiens than each other.

(it's a theory anyway)
posted by tgyg at 7:24 PM on November 8, 2006

Hotlegs!
posted by tellurian at 10:43 AM ACST on November 9

OK folks - we know what the band's title (10cc for those who haven't followed the link) is all about - right?

Highly relevant to the whole transference of DNA material/evolution topic methinks.
posted by Sk4n at 8:23 PM on November 8, 2006

Neanderthals may have been more talented in certain ways than the average Homo Sapien (of the day), but they is UGLY. Even today, beauty trumps brains. Neanderthals died out because even the Neanderthals prefered screwing the Homo Spaiens Sapiens than each other.

I dunno. The Scotsman link says that h. sapiens was more likely to travel and make friends than h. neanderthalensis. Seems to me that those traits come in handy in more ways than one.

Why on earth would you bother adapting to German spelling changes that took effect after we borrowed the word?

Mainly because of all the scientists who say Neandertal. Like Hawks. Google tells me they're a minority even in the US, where the usage seems to be more common (4:1 in the US, 7:1 in the UK).

Anyway, I just love the etymology of Neanderthal, with or without the "h". Neander is Greek for new man, which was the public name taken by theologian Neumann, after whom the valley was named. It seems that "new man" continues to surprise us.
posted by dhartung at 10:13 PM on November 8, 2006

Newman!
posted by Pollomacho at 11:03 PM on November 8, 2006

Neanderthals may have been more talented in certain ways than the average Homo Sapien (of the day), but they is UGLY. Even today, beauty trumps brains. Neanderthals died out because even the Neanderthals prefered screwing the Homo Spaiens Sapiens than each other.

heh. I like it, but have you been to a mall, or a NASCAR race, or any other public place recently? Sometimes, when you can't have beauty, you settle for what's available. I hereby declare this to be the "fat chicks need love too" rebuttal to your theory.

Anyway, moving on. I have a few problems I with the wholescale adoption of H. neanderthalensis as a viable partner for H. Sapiens in the horizontal mambo, specifically in relation to this study. According to Evans et al. halpogroup-D exited what would become the H.s lineage ~1.1Mya, then re-entered the lineage ~37Kya. On the one hand this age of diversion supports the idea that H.n would be the possible resevoir for this gene, since investigations into mitchondrial DNA has suggested that H.n diverged from H.s a long time ago, possibly back when we were all just Homo erectuses (erecti?). In fact, even the articles quoted above cite the divergence of H.n and H.s as ~500Kya. Which raises the question: Why weren't we getting busy with each other for the first 600K years? This ancient seperation also lends credence to the proprosal that, by ~40Kya H.s and H.n had diverged too much to produce viable offspring.

On the other hand, the re-entrance ~37Kya presents another problem. H.n and H.s were in contact during that whole period. For example, Qafzeh, in Lebanon, shows evidence of fully modern anatomical H.s ~100Kya, then a replacement by H.n ~80Kya, followed by yet another replacedment of H.n by H.s ~40Kya. There's a lot of this in the Levant; H.n and H.s overlapping at the same site. This has even supported some theories of interbreeding based on morphology, but more on that later. The point I want to make is that H.n and H.s had plenty of opportunities to interbreed prior to 37Kya. One thing all Neandertals did have in common ~37Kya is that they were all dead. The last evidence for living H.n populations is ~40Kya. While this may support Maias "rape and pillage" model of replacement, it still doesn't explain why H.n and H.s weren't fucking before then.

Finally, trying to classify species based on narrow morphological (particularly highly variable cranio-facial) characteristics is always tricky. The National Geographic study above cites Erik Trinkaus (who is a long time proponent of H.n and H.s hybridization) saying that the remains found in Petera Muierii look like H.s but include some telltale H.n features including "the shape of the lower jaw and the back of the skull." I don't know for sure, but I assume he is referring to the occipital bun and receding gnathion (that's the chin) so indicative of H.n. The problem is that occiptal buns and receding chins are found in H.s populations across the globe and are not unique to H.n.

Anyway, what I'm trying to say is this: If H.n and H.s did interbreed that would be fucking awesome on a whole lot of levels, but so far the genetic and morphological evidence all points to a great big "maybe."
posted by TheSpook at 11:45 PM on November 8, 2006

maybe this will clear up your issues, at least regarding the Levant, TheSpook:

When men began to increase in number on the earth and daughters were born to them, the sons of God saw that the daughters of men were beautiful, and they married any of them they chose. Then the LORD said, "My Spirit will not contend with man forever, for he is mortal; his days will be a hundred and twenty years."
The Nephilim were on the earth in those days -- and also afterward -- when the sons of God went to the daughters of men and had children by them. They were the heroes of old, men of renown.
posted by Pollomacho at 12:23 AM on November 9, 2006

I don't see any serious race implications, intelligence is not just some function of cranial capasity!

I'm not sure "European" is correct here, the blog say Asians have this gene too. Its only Africans who don't have it & it sounds linked to cold weather survival.

Hawks makes it clear that humans *could* interbreed with neandertals.
posted by jeffburdges at 1:38 AM on November 9, 2006

Pollomacho, that appears to be an interesting longitudinal study, and I see also that it has been widely translated. The original data appear, however, to have been lost. I think we'll have to take its conclusions on faith.
posted by dhartung at 2:05 AM on November 9, 2006 [1 favorite]