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Oldest Human Genome Reveals When Our Ancestors Mixed With Neanderthals
sciencehabit writes DNA recovered from a femur bone in Siberia belongs to a man who lived 45,000 years ago, according to a new study. His DNA was so well preserved that scientists were able to sequence his entire genome, making his the oldest complete modern human genome on record. Like present-day Europeans and Asians, the man has about 2% Neanderthal DNA. But his Neanderthal genes are clumped together in long strings, as opposed to chopped up into fragments, indicating that he lived not long after the two groups swapped genetic material. The man likely lived 7000 to 13,000 years after modern humans and Neanderthals mated, dating the mixing to 52,000 to 58,000 years ago, the researchers conclude. That's a much smaller window than the previous best estimate of 37,000 to 86,000 years ago.
Someday they'll figure out "Neanderthal" is a completely artificial distinction, like "White Aryan", and the scientific consensus will be that Neanderthals R Us.
The same tests on DNA from another man from the same era and locale but from a different Y-haplogroup (and different mt-haplogroup) might show a completely different proportion of genetic mixing and time to most recent mating. Don't draw too many conclusions from a sample of just one.
This can't be right. The world is only 2014 years old!
Does not conclusively prove. Mixing could have occurred at many times and locations. While useful, more data needed.
Silence is a state of mime.
My guess is that the fact that no organisms exist with a Neanderthal genome defines them as extinct. Where one draws the line is more art than science I guess. There is a species of Galapagos tortoise that was biologically extinct since there was until recently just one male member (lonesome George). I know that there are some genetics in us (like the HMG group of proteins) that are ancient, but work so well that we still retain them. That doesn't mean the first species to have evolved them isn't extict, it just means we evolved from them.
Group of genes, not protiens! My bad.
Realize that 80% of the human population lives in abject poverty. The "trailer trash" are already above the average human condition.
The author's cro-mag bias is showing.
Her title implies that the neandertals in question are not also our ancestors.
A better title might have been "...genome reveals when our Cro-Magnon ancestors had sex with our Neandertal ancestors."
I belong to the group having two to four percent Neanderthal in me and I still haven't scored with a pure blooded homo sapiens, you insensitive clod!
How accurate is it for the media to say a "complete" genome was sequenced? I know a little molecular biology and have been lead to believe that certain types of DNA, (centromeres, telomeres, other such regions with lots of repetitive sequences or "fragile sites") are very hard to sequence reliably. Are these "swept under the rug" in a "complete" sequence? Perhaps a related question, how are non-coding regulatory portions of chromosomes handled in whole genome analysis?
Stay sentient. Don't drink bad milk.
The summary refers to the time when neanderthals and modern humans intermixed, but can we really call what came before the mixing modern humans? It seems that something about the combination sparked huge evolutionary changes that allowed us to rather rapidly (evolutionarily speaking) develop modern society. As far as I'm concerned, the history of modern humans starts with the mixing.
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it couldn't be measured if it weren't a distinct genotype. That says nothing about speciation, of course.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
So by what metric are Neanderthals extinct, if there are Neanderthals who have living descendants with a measurable amount of their genetic makeup?
There is no living population, large enough to produce additional generations of viable offspring, with a full, or substantial, Neanderthal genome.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Drawing hard lines in the sand is perhaps not possible. Neanderthals would share a vast majority of our DNA just by being hominids. There are clusterings of genetic patterns, but a cluster is not a clear-cut distinction.
Table-ized A.I.
My guess is that the fact that no organisms exist with a Neanderthal genome defines them as extinct. Where one draws the line is more art than science I guess ... I know that there are some genetics in us (like the HMG group of proteins) that are ancient, but work so well that we still retain them. That doesn't mean the first species to have evolved them isn't extinct, it just means we evolved from them.
Well, I don't think that quite matches the scientific concept of "species". By your definition, almost all species who were alive 50,000 years ago would be considered extinct, but hardly any biologists would agree with that. It's true that no humans alive today have 100% Neanderthal genes, but it's also nearly certain that there are no living humans with 100% Cro-Magnon genes, either. What happened would be considered a mixing of several human sub-species after migrations of one or more African groups into Eurasia. The Cro-Magnon sub-species disappeared, too, and modern human Caucasian and Asian sub-species are the results of that mixing. This sort of thing happens in species all the time, when conditions allow such genetic mixing, and the result is rarely considered a new species.
The fact is that modern humans are all one species. We can and do interbreed when groups mingle, and there are no groups of modern humans that are genetically incompatible. If sub-species "disappear" by genetic mixing, that is usually not called an extinction event. It's just the routine and normal mingling of subspecies.
An interesting contrast is that most North American duck species are known to hybridize occasionally, and the offspring are usually fertile. Does this mean they're really all one species? No, because they all mingle a lot, but interbreeding is rare. They have "behavioral" species-separation features, mostly based on female mate choice. The females are mostly all mottled brown (protective coloring), and the males often approach females of other species (because they can't tell them apart either ;-). But the females usually only accept males that have the "right" color markings; the others are ugly to them. This suffices to keep the species separate, though there is probably a very low level of genetic interchange between many of the species.
But humans aren't like this. Even if we do generally prefer mates in our own subspecies, most of us do find many members of other subspecies physically attractive, and we'll mate with them given the opportunity. This means that we really are all the same species. We now have good evidence that the Neandertals were merely another subspecies, because when they had the opportunity, they did interbreed with those slender, dark-skinned folks who migrated into their territory. They did so often enough to produce a new subspecies that's physically distinct from either of the earlier two (or three or more).
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
This seems like circular logic. First one has to define what a "Neanderthal" is before answering that question.
Table-ized A.I.
I think that some of those Africans look a little bit more Homo Sapien than Europeans who have the Neanderthal Genes.
A little bit more upright, less stooped, a little bit less hairy, a little mound of forebrain in their foreheads.
There's a lot of genetic variation in Africa by comparison though. I'm thinking of those tall, really black-skinned, Sudanese looking people.
Exactly. Look at chimpanzee's that share about 99% of human's DNA. Neanderthals would have to be much closer.
We've got to stop with the Neanderthal nonsense...
Neanderthals are *not* the magical missing link, nor does proving/disproving the existence of God or the truth of the theory of Evolution...none of this is in play
This is about legacy academia and how century-old academia wars are burdening good research today.
Another example: Clovis Culture http://www.examiner.com/articl...
Clovis Culture theory has been the bane of anthropologists and archaeologists for decades...the only reason it was so entrenched is b/c of flaws in academia.
Neanderthals are the same. The whole notion of "Neanderthals" being a separate thing is just a miscategorization of traits that modern humans have. Maybe they are rare, and have become less attractive over the millenia, but not any different than any other trait.
Look at Russian boxer Nikolai Valuev
The traits we collectively call "Neanderthal" are a distinction without a difference.
It's a failure of science that some ideas are irrationally difficult to disprove. Usually it is because people are using the research wrongly to prove a non-science point.
Again...Neanderthals can be variations on modern humans and it **does not disprove evolution!!!**
Thank you Dave Raggett
Strangely enough, beer was invented 57,999 years ago.
"The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
There's no such thing as beastiality.
Indeed.
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Homo sapiens neanderthalensis is also a classification used by some.
Well, I don't think that quite matches the scientific concept of "species".
There is no generally-agreed-upon "scientific concept of species". The "Biological Species Concept" is a well-know and highly contentious artifact. It is clearly useful, but how it is defined varies enormously from person to person and across sub-fields.
This variation doesn't matter much in practice, but it gives philosophers who for some unfathomable reason want there to be just one BSC fits. They seem unaware that concepts are tools used by knowing subjects to understand objective reality, so different subjects with different purposes will tweak the tool as appropriate, much the way a carpenter and a plumber are apt to use different types of hammer.
Blasphemy is a human right. Blasphemophobia kills.
If we could breed with it and the offspring was fertile, I guess there's a reason why some people still insist on calling them Homo sapiens neanderthalensis instead of just Homo neanderthalensis.
Ezekiel 23:20
I can tell the same by looking at some of my neighbors
We've got to stop with the Neanderthal nonsense...
Right we do. There are just a few pieces of evidence now, but it may be that Neanderthal is actually a distant race that falls within our human specie. If their whole genome diverged from the branch of modern humans ~600,000YA and yet --- if there is additional evidence of interbreeding up to ~50,000YA, and humans from ~50,000YA could interbreed with us today (which I believe is true) --- then I consider it extremely likely that a Neanderthal could breed with a modern human.
And give your children superpowers like X-ray vision.
This is vindication for Jean Auel, whose Earth's Children series of books has popularized this exciting idea for generations of children. As a lay author she has been the lightning-rod target of those who disagree with the hypothesis, and at times her literary critics have even betrayed a tone of indulgent arrogance that just might have been a glimmer of the old Darwinian stuffed shirts, who banished Neanderthal from the human family early on by some of the characteristics that (merely) differentiate races existing today. Central to all of this goofy criticism is the Ayla's hybrid child Durc.
I highly recommend Earth's Children books to all. They are on par with Tolkien in their use of descriptive language, the central characters portray a series of actual humans over time who have made technological discoveries over time. The books are especially fit for children as they imagine the rich and viable human society that we know must have existed long ago, dispelling the silly myths that what we would recognize as civilization is merely a few thousand years old.
<blink>down the rabbit hole</blink>
I'm with you on this, however you must be aware that a lot of different species can actually interbreed. It's just that biology is 10% science and 90% fluff.
The Cro-Magnon sub-species disappeared, too, and modern human Caucasian and Asian sub-species are the results of that mixing.
Modern thinking suggests there was no Cro-Magnon subspecies, and that scientists of the time were actively looking for differences, hence ignored that the dimensions of the cro-magnon specimens were within the variation found within modern humans. Remember, prior to World War II, "racism" was more or less considered a branch of science. In Frank Herbert's Dune, there is an obsession with finding "humans" and separating them from "animals" by breeding, and while it's easy to rationalise that away as a Nazi reference, but that's just choosing to ignore that a lot of people felt that way elsewhere. While most of the world abandoned eugenics after the war, there are some who lament the Nazis giving a "bad name" to it. Eugenics even continued in parts of the US, through mandatory sterilisation of the mentally disabled, which was extended to African Americans with poor school records. There was a continuing assumption among many that black Africans were an "inferior race" and therefore just pollution to the genestock. Elsewhere, the colonial powers justified their continued occupation of their remaining territories through the condescension that these foreign types just weren't capable of ruling their own countries, and so we were doing them a favour by lending them our superiority. For all this time, scientists were looking for individual homonid species/subspecies as ancestors of the "races" that we had invented in modern populations based on little more than melatonin levels and eye shape.
Yes, I've gone off at a tangent. A very long tangent. My point is that in matters of human evolution, generations of science were led by the nose in order to rationalise the prejudices of the privileged few. Modern science, thankfully, has proper data to work with -- DNA. Neanderthal DNA has been sequenced from Neanderthal fossils, and it differs from Modern Human DNA in ways that are measurable and quantifiable. It denies the old claim that white man was neanderthal and therefore a distinct race from Africans, or that Basques are Cro-Magnon and a different species from everyone else in Europe.
Neanderthaler was different enough to be of note and is extinct. A few genetic markers remain, but most of the unique DNA is lost.
But humans aren't like this. Even if we do generally prefer mates in our own subspecies, most of us do find many members of other subspecies physically attractive, and we'll mate with them given the opportunity. This means that we really are all the same species. We now have good evidence that the Neandertals were merely another subspecies, because when they had the opportunity, they did interbreed with those slender, dark-skinned folks who migrated into their territory. They did so often enough to produce a new subspecies that's physically distinct from either of the earlier two (or three or more).
I find your use of human subspecies troubling -- it harks back to the institutional racism of pre-genomic science (there was a point to my earlier rambling after all). Neanderthal may have been a subspecies rather than a fully-fledged species (debating that would be irrelevant here) and that definition would be based on marked genetic differences and rare interbreeding with early modern human populations. But the genetic differences between human racial groups is not on the same level as subspecies -- in fact, as I understand it, it's less than between different breeds of domestic dog, and all domestic dogs are lumped under one single subspecies: canis lupus familiaris.
Even though you didn't intend to, your argument implies that the difference between Neanderthaler and Modern Human is on the same order of magnitude as the difference between black African and white European. That's not a road we want to start back down.
Got them moderator blues I blieve I walk out the do', With these mod-points I been gettin', I 'most never post no mo'
Someday they'll figure out "Neanderthal" is a completely artificial distinction, like "White Aryan", and the scientific consensus will be that Neanderthals R Us.
If by "artificial distinction" you mean the classification of lifeforms into different groups based on physical and genetic characteristics, the boundaries of those classifications made by scientists, then you have a valid point. A species is generally understood as a population that can interbreed and produce viable offspring. Homo sapiens and homo neanderthalis obviously can do so, so they should be the same species. However, there is a valid argument for them being classified a subspecies, due to measurable physical and genetic differences.
The Moore-Murphy Law: The number of things that will go wrong will double every 2 years.
Except... tigons and ligers.
Got them moderator blues I blieve I walk out the do', With these mod-points I been gettin', I 'most never post no mo'
Judging by one of my coworkers I'd say it was still going on around sixty years ago.
A species is generally understood as a population that can interbreed and produce viable offspring. Homo sapiens and homo neanderthalis obviously can do so, so they should be the same species.
That's a very poor understanding of speciation.
For example, consider ring species: species A & B can breed and species B & C can breed, but species A & C cannot.
For example, consider ring species: species A & B can breed and species B & C can breed, but species A & C cannot.
Good point. What if Neanderthals could create viable offspring with Homo Erectus but modern humans couldn't?
Life is messy.
The Moore-Murphy Law: The number of things that will go wrong will double every 2 years.
I checked it out...seems interesting
I kind of wish we could just ditch "neanderthal" and "cro-magnon" from the lexicon entirely...Cro-Mags are "AMH" and IMHO all the evidence shows that Neanderthals are AMH as well...so let's start from scratch with the genomic comparisons and make a new nomenclature
Back to Earth's Children....from reading the wikipedia, it seems like it might be similar to the film "Clan of the Cave Bear"
Thank you Dave Raggett
Mod parent up. Here is a discussion of the various definitions of "species"; also, it's worth clicking through to this list.
That's the first book in the series.
It was made into a film 6 years after the original book, after she had written the second and third books.
Man is the animal that laughs.
And occasionally whores for Karma.
...
Just addressing the example given - the "Cro-Magnon" concept and term has been entirely abandoned by science. The problem was that there was never a definition of what a "Cro-Magnon" supposedly was. No distinguishing set of physical characteristics, no distinctive physical culture, and now with our powerful genetic analysis tools - no distinctive genetic pattern. Their range of variation is within that of modern humans, and supposing they were a subspecies would be as well founded as declaring "Samoans" a subspecies since they are, like the "Cro Magnon" physically more robust on average than modern Europeans.
Second class citizen of the New Gilded Age
This much older modern human has the same fraction of Neanderthal DNA as modern humans today.
Think about it.
We haven't seen any ancient Modern Humans that have a different degree of Neanderthal ancestry.
When Modern Humans first bred with Neanderthals the offspring were 50/50. If these F1s bred with each other predominantly from then on you would end up with a new breeding population that was roughly 50/50 in heritage. If the F1s predominantly bred with Modern Humans, then the Neanderthan portion would be cut to 25% in the F2, and if the process repeats it is 12.5% in the F3, etc.
This process stops when there are effectively no more pure blood Modern Humans, that the Neanderthal genome has diffused evenly across the entire population. But subsequent re-encounters would inject new Neanderthal DNA and restart the process.
We haven't yet seen any evidence of this history yet. Even 45,000 years ago it was "ancient history" and epoch that passed many, many generations earlier.
Second class citizen of the New Gilded Age
This seems like circular logic. First one has to define what a "Neanderthal" is before answering that question.
Yep. A lot of taxonomy is like that.
In the process of classifying things they're trying to find or define sharp boundaries on a subject matter that is actually a continuum.
I recall, in my first encounters with the subject, trying to get a coherent definition of the distinctions between species, genus, family etc.. The instructor was utterly uanble to provide one. (Of course this WAS at the junior-high level.)
DNA technology is also substantially revamping the whole field. Previously they had to infer what genes various organisms had by observing their expressions in morphology - which makes it hard to track genes that are there but "turned off". Now that they can actually sequence the DNA (or the expressed protiens when the sample is too old for DNA and RNA to survive) a lot of the classifications are getting rearranged.
Was Neanderthal a species, or something more akin to a colorform? What constitutes extinction when a branch that once interbred with another dies out, but leaves behind a substantial amount of its DNA? Did the two branches actually "speciate", i.e. separate to the point where the COULDN'T interbreed, or at least couldn't produce viable crossbreed offspring that could produce offspring of their own in turn? Or was it just that they mostly DIDN'T interbreed? Were they like the races of the current human species (clusters of different traits but one big gene pool), like horses and donkeys (where crossbreeds are easy but mostly infertile), or like fully-speciated organisms that might try but just can't produce offspring? Did they go extinct, or did most of their traits just gradually (or suddenly, as in a near-extinction event where all the copies of a gene were in the places where everybody died off) get lost from the geneome of the one big human family?
Seems to me it's mostly a matter of definition and partly a subject for more research.
Don't ask me for an authoritative definition. I'm just another observer, not a taxonimist. B-)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
What's a Neanderthal? What's a Cro Magnon?
Basically, these are names assigned to groups of fossils with similar bones. Sufficiently similar, for some nearly arbitrary value of sufficiently.
FWIW, it is my belief that they typical Neanderthal woman had a pelvic girdle to tight to pass a Cro Magnon baby. (The adults definitely had very differently shaped heads, though what that means is subject to doubt.) This explains nicely the lack of Neanderthal mitochondria in our genome. And it means that while Neanderthal males could successfully mate with Cro Magnon women, the converse didn't work out. As a result heads shaped like the Neanderthal disappeared from the gene pool, and any genes for producing them, and any genes that were tightly coupled with them.
OTOH, I haven't heard anything about the shape of the heads of the Denisovians. Some people have some of their genes, too.
It is my belief that Cro Magnon/Neanderthal/Denisovian is all one species, and that splitting them into separate species is an error, one fostered througout palentology, not just in this case, because it is much more important to discover a new species than to discover a new population with some unusual features.
OTOH, please note that species boundaries are nowhere near as absolute as normally thought. Often there will be diverse populations of a single species clustered in a spread out area, with the populations at the extremes of the area either unable or unwilling to interbreed, even though there is a continual flow of genes throughout the cluster, i.e., every adjacent population is willing to breed with its neighbors.
I think we've pushed this "anyone can grow up to be president" thing too far.
whoa!
mind=blown
Thank you Dave Raggett
. Note that the article also suggests that not all neanderthals were white, either. Note also that other traits often erroneously claimed to be neanderthal (blond hair, red hair, blue eyes) have again been shown not to be part of the neanderthal genome.
Got them moderator blues I blieve I walk out the do', With these mod-points I been gettin', I 'most never post no mo'
yet again, ring species.
Jean Auel's work is literate smut. It's just a Stone Age bodice-ripper. Don't make me quote-mine for proof.
Calling it a 'bodice ripper' is obscene.
Earth's Children series comprises six books, ~1.8 million words altogether.
In Clan of the Cave Bear There is brutal sex without consent. It occurs within the context of a culture that does not require a woman's consent, which is how Auel chose to portray the Neanderthals --- yet it is clear that among the clan brutality is not tolerated. This is essential to the story... and a series of encounters between Jondalar and Ayla appearing throughout the books that are as sensual and vivid as one might expect of a young couple in love, sex done 'right'. The scenes are described in extravagant (if you hate sex you might prefer 'lurid') detail. Auel's writing style is strained a bit during these sex passages only in that there are some repeated words and phrases, the cutest of which is the use of the word nodule.
But the lovers are soon satiated and the story moves on, just as it does in real life. It does not detract in the slightest from the series. Do not expect a 'did this, said this' style where the characters' minds are opaque and clumsily presented. Auel is a masterful writer who jumps skillfully between expressed inner thought, dialogue, and the senses.
But her portrayal of Earth's primordial landscapes and the journey/adventure is the real treasure one will find in these books. An avid reader not only sees through the characters' eyes, even down to the minutiae of making camp, it becomes possible to place yourself there, so well is it described. I loved the way Tolkien describes Ithilien and always wanted to tarry awhile without a burdensome ring quest. For me, Earth's Children recaptured that feeling.
I do not hesitate to recommend these books to any child who is old enough to read them, even the unpleasant explicit content within 'Cave Bear'. We do not live in a perfect world where there is no need to learn of such things, and that book portrays brutish and bully behavior in its complete context of the character's jealousy and malice. Many might consider these to be 'adult' themes, but my position is that they are just themes that children are sure to encounter in their lives. There is no 'right time' to introduce kids to these things only a 'right way'. The author neither glorifies nor apologizes for them. Books like these help prepare children for life.
Sorry to bore you. Back to the sex. Here is a Google search for "Ayla's nodule for your enjoyment and titillation. Now get off my lawn.
<blink>down the rabbit hole</blink>
Last I remember all the neanderthal specimens were discredited by highly secular sources.
The original fossils were mixed with clearly human fossils, but were later determined to have a condition called rickets.
So, yeah, this one seems a little made up to me, and I don't blame the 58% of Americans who don't believe in evolution.
If all the species are related, why are there all these shenanigans?
The latest big finding on Neanderthals: Some 20% of caveman DNA made its way into the human genome thanks to mating between humans and Neanderthals, though people today typically have only 1% or 2% of the stuff. (People have different parts of the DNA, which collectively represent what's left of the Neanderthal genome.) The results come compliments of two studies. Standout details: In one study of 1,004 people, Harvard researchers wanted to determine which populations have the most Neanderthal DNA; East Asians ranked ahead of Europeans, at 1.4% versus 1.1%, respectively, Reuters reports. (Africans essentially have no Neanderthal DNA, as Neanderthals never lived there.) That backs up a 2013 study, notes Reuters, but the researchers went beyond previous findings with this observation: Though Neanderthals are thought to have died out on the Iberian peninsula 28,000 years ago, Spaniards exhibited some of the smallest amounts of Neanderthal DNA, at 1.07%. As such, Neanderthals "are not fully extinct, if you will," a co-author of the Harvard study tells the Los Angeles Times. "They live on in some of us today—a little bit." The second study also compared the genomes of Europeans (379 of them) and East Asians (286), and found a similar heavier "genetic signature of Neanderthals" among the latter. A co-author tells the LAT that might indicate a second series of matings happened. "It's a two-night-stand theory now." The University of Washington geneticist also shared this observation: Based on the amount of our genome that comes from Neanderthals, he thinks the two species "mated perhaps 300 times about 50,000 years ago," per the LAT, though it's unclear whether that happened in one wave or over generations. Both studies reached a shared conclusion: that natural selection smiled on the Neanderthal genes that make skin and hair tough (possibly providing thicker insulation), and they remain common in populations with Neanderthal genes today, the New York Times reports.