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  (Source: 20th Century Fox)
But can they sing? And was Dr. Zaius involved?

Chorus: "He can speak, he can speak, he can speak!"
Troy McClure as Taylor: "I can singggg!"
"Planet of the Apes: The Musical" from The Simpsons epsiode "A Fish Called Selma"

A research team at the Max-Plank-Gesellschaft Institute's (MPI) Psycholinguistics department has analyzed recent discoveries on humans' close relatives -- the Neanderthals (Homo neanderthalensis) and Denisovans (Denisova hominin) -- and offered a controversial hypothesis.  They propose that Neanderthals, and likely Denisovans had languages and that these human relatives likely spoke with humans during their interactions.

Recent DNA discoveries have cast new light on the interactions of humans and their relatives.

Once viewed as dumb and brooding hunter-gatherers, Neanderthals inhabited much of western Eurasia from 350,000 to 600,000 years ago, and later migrated back to Africa.  But new evidence shows that Neanderthals actually had larger adult brains than humans, a very similar genetic makeup, and advanced tool use.  What's more there is strong evidence they exchange culture -- trading with early humans -- and even more shockingly had sex with them, producing offspring.  Much of the interbreeding appeared to occur when humans and Neanderthals migrated back to Africa some 50,000 to 80,000 years ago.

Neanderthals
Neanderthals interbred and traded with humans in Africa and Europe. [Image Source: AP]

The simplistic world-view was further shaken by the discovery of the Denisovans -- another ancient relative that remained unknown until archaeological finds and gene research in the latter half of the last decade.  Like Neanderthals, Denisovans appear to have enjoyed a prosperous interaction with the locals some 30,000-300,000 years ago.

The evidence of rich ongoing interbreeding with each group suggested that these genetic exchanges weren't examples of raping and pillaging.  There's strong evidence some humans on their own free will bedded these relatives intermixing their lines for long stretches of time.

Family tree
The human family tree is much more complex than previously thought. [Image Source: MPI]

MPI Professors Dan Dediu and Stephen C. Levinson say that this indicates that early man must have been able to communicate with his early relatives; they must have been capable of speech.  They argue this hypothesis is further supported by the lack of discovery of a single or handful of "magic" genes that alone "create" the capacity for speech.

Rather they argue that speech evolved between the emergence of the Homo genus 1.8 million years ago and the emergence of Neanderthals, Denisovans, and Humans common answer -- Homo heidelbergensis some 600,000 to 1.3 million years ago.

In a press release MPI writes, "This reassessment of the evidence goes against a saltationist scenario where a single catastrophic mutation in a single individual would suddenly give rise to language, and suggests that a gradual accumulation of biological and cultural innovations is much more plausible."

speech bubble
Humans might not have a monopoly on speech. [Image Source: Career Realism]

The researchers suggest that differences between European and Asian languages may be attributable to traces of lost Denisovan and Neanderthal languages that crept into the speech of the humans who interacted and interbred with them.  They suggest further work be done to model language spread with computer simulations and to compare the structural properties of the African (where humans interbred with Neanderthals) and non-African languages (where humans may have bred with Denisovans).

The pair have published [abstract] their paper in the journal Frontiers in Language Sciences.

Sources: Max-Plank-Gesellschaft Institute, Frontiers in Language Sciences



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A rose by any other name is still a rose.
By drycrust3 on 7/15/2013 2:03:22 PM , Rating: 2
quote:
The researchers suggest that differences between European and Asian languages may be attributable to traces of lost Denisovan and Neanderthal languages that crept into the speech of the humans who interacted and interbred with them.

If there are children produced from the union of Homo sapiens and Homo neanderthalensis, doesn't that suggest they are actually the same species, and that what you are looking at is just different races, just like Americans, Chinese, Koreans, Indians, American Indians, etc?
I reckon that if they went and did a mitochondrial DNA analysis on these "different species" of humans they'd find they have the same "Mitochondrial Eve" genetic code in them as appears in all Homo sapiens, and if that is correct, which it will be, then these "different species" are actually Homo sapiens.




RE: A rose by any other name is still a rose.
By Reclaimer77 on 7/15/2013 4:05:00 PM , Rating: 2
Not really. Certain separate species can inter-breed like lions and tigers, or wolves and coyotes. That doesn't make them the same species though.

As far as to the why, well, that's over my head. DNA..genes..bla bla.


By maugrimtr on 7/16/2013 11:11:25 AM , Rating: 2
Depends on far your DNA drifts. Species need a really long time to evolve separately after a split in the population to have enough divergence that mixed mating is fruitless. Humans actually had a very short time. Pretty much any ancient human could mate with any other ancient human most likely - geographic separation just lowered the odds of it happening which is why mass migrations between Africa and Europe/Asia were so important.

You have to see the funny side. The Neanderthals and Denisovans did not become extinct. All of us from Europe, Africa and Asia have 4-6% of our DNA from our so-called inferior and primitive cousins (an important part of it being improved immune systems).

The only close to pure Homo Sapiens on the planet are natives from North and South America who became isolated from Asia/Europe/Africa when the land bridge between N. America and Asia was flooded, and who never got the chance to interbreed with the contaminated bloodlines of half breed Europeans and Asians.

On Lions/Tigers - also Jaguars and Leopards - these all belong to the same genus "Panthera" (just as we belong to the "Homo" genus that includes Neanderthals) and can interbreed to varying degrees of success and liklihood. Cheetahs belong to a different genus (and they can't interbreed with other big cats) just as Apes and Chimps/Bonobos can't interbreed with us.


RE: A rose by any other name is still a rose.
By charleski on 7/15/2013 5:24:29 PM , Rating: 2
If they interbred and the offspring were independently fertile then they would indeed be the same species.

There are many examples of different species interbreeding and producing infertile offspring, the most common example is the mule (offspring of a male donkey and female horse) - all male mules are sterile as are the vast majority of females, so male and female mules could never have foals. (Female mules can, very rarely, produce offspring when mated with a horse or donkey.)

It's been suggested that modern humans carry small amounts of Neanderthal DNA. If true, this could possibly have happened through interbreeding with the offspring then mating back among purebred humans. Unless human/Neanderthal offspring were able to breed together the species distinction would be maintained, however.


RE: A rose by any other name is still a rose.
By maugrimtr on 7/16/2013 11:23:43 AM , Rating: 2
quote:
It's been suggested that modern humans carry small amounts of Neanderthal DNA.


It's not a suggestion, it's regarded as fact. DNA analysis is pretty plain that Europeans got 4% of their DNA from Neanderthals, i.e. the mixed breeding gave us significant benefits and spread across the entire population. It's almost certain the benefit was a better immune system for ex-African diseases. Asians got similar benefits from Denosovan DNA.

Worth noting that Neanderthals and Denosovans also interbred indepedently of modern humans so unless you hid away in the Americas separate by an ocean, you are at least 2-6% Neanderthal (majority of that 6% being Denosovan if from Asia).

quote:
Unless human/Neanderthal offspring were able to breed together the species distinction would be maintained, however.


They obviously could but, geography would have made it impractical unless there was a shared Sapien/Neanderthal population centre. It's a moot point - all that matters to us that those with Neanderthal DNA were better survivors and the DNA spread. The half breeds won a gamble at the Evolution table and many of us are descended from them.


RE: A rose by any other name is still a rose.
By drycrust3 on 7/16/2013 5:11:51 PM , Rating: 2
quote:
Worth noting that Neanderthals and Denosovans also interbred indepedently of modern humans so unless you hid away in the Americas separate by an ocean, you are at least 2-6% Neanderthal (majority of that 6% being Denosovan if from Asia).

So if you can test the genome of a body buried thousands of years ago to the point you can tell how many genes are still present in the human population today, why is it so difficult to test to see if they share our descent from "Mitochondrial Eve"? Since I don't know anything about the technology or process, my guess is it isn't any more difficult.
Which leads us back to the second question: If all of those other "human species" have the same common ancestor as us, aren't they also the same species as us? The answer, of course, is they are the same species as us.


By charleski on 7/21/2013 3:11:05 AM , Rating: 2
They're the same genus. Species diverge from a common ancestor, and once they've diverged enough they're separate and can't mingle back with each other.


By charleski on 7/16/2013 8:43:39 PM , Rating: 2
quote:
It's not a suggestion, it's regarded as fact.

There's some very interesting evidence, but the correspondences could still be the result of a degree of common ancestry rather than interbreeding. It seems likely that humans and Neanderthals interbred, but it's still very far from being a fact.

quote:
quote:
Unless human/Neanderthal offspring were able to breed together the species distinction would be maintained, however.

They obviously could

Nope, not obvious at all. The most likely scenario would involve female human/Neanderthal hybrids backcrossing into the human gene line and passing on a few segments of Neanderthal DNA to those offspring that survived. Models of DNA transmission that would account for the Green et al. results come up with extremely low levels of interbreeding. See http://www.pnas.org/content/108/37/15129.short and http://www.plosone.org/article/info%3Adoi%2F10.137...


RE: A rose by any other name is still a rose.
By Fritzr on 7/18/2013 4:18:25 AM , Rating: 2
No, there are documented edge cases where the hybrids breed true to type. The Red Wolf is only found where Coyote and Grey Wolf ranges overlap. Coyote-Grey Wolf hybrids are Red Wolves & there is a stable breeding population of Red Wolves descended from these hybrids.

Dog-Wolf hybrids are also fully fertile, though it is now thought that dogs ARE wolves. The problem with that is the various traits of dog that enable them to work with and read humans. Timber, Grey and Red wolves lack this ability as do Coyotes.

Domestic dogs have unique abilities that enable them to understand human speech and signals while retaining the ability to successfully breed with all Wolf and Coyote varieties.

Dogs are a unique species that is still able to interbreed with multiple closely related non-dog species.


By charleski on 7/21/2013 3:19:52 AM , Rating: 2
Er, yeah, I mentioned the Canis hybrids already. This is an edge case where the chromosomal organisation of the genus permits extensive mingling. One solitary genus has little impact on the concept of reproductive isolation, though.


RE: A rose by any other name is still a rose.
By Keeir on 7/15/2013 7:35:26 PM , Rating: 3
Species are defined more by a variation of conformity rather than particular reproducability.

Species that are relatively close together are more likely to be able to have cross species reproducability. (But potentially not)

In this case, fossils suggest Neanderthals differed significant from "Homo Sapiens" type in conformity. Genetic analysis also suggests significant deviations of genes. Certainly Homo Sapiens and Neanderthals were very close, but crossbreeding does't really play a role.

(Remember plants are cross breed all the time)


RE: A rose by any other name is still a rose.
By charleski on 7/15/2013 10:13:17 PM , Rating: 2
You need only go to a dog show to see how one species can exhibit huge phenotypic variation. Modern interspecific plant hybrids are produced using highly artificial techniques to induce chromosomal rearrangements - that's not really a good counter-example. A better one would be the Canis hybrids, which can occur without genetic intervention and are often fertile - for example a dog can mate with a coyote, and there are accounts of wild populations of dog/wolf/coyote hybrids: http://www.jstor.org/stable/3671304

These are edge-cases, though. The definition of a species is still problematic at times, but Mayr's concept of reproductive isolation (which I outlined above) remains the most widely accepted.


RE: A rose by any other name is still a rose.
By Keeir on 7/17/2013 9:43:29 PM , Rating: 2
I doubt that many "species" are conclusively tested for true reproductive isolation.

I think its also a stretch to assume that any/all Homo Sapiens/Neatherthal pairings would fit the "natural" category. In the time period of potential "crossings": culture, language, and force multipliers all existed.

I also think its interesting that in one sense you embrace extremely artificaly means to exagerate phenotypic variation. But even with the clear visual difference, the bone structure and sensory organs of dogs are extremely similiar and function in extremely similiar fashions.


RE: A rose by any other name is still a rose.
By charleski on 7/21/2013 3:07:36 AM , Rating: 2
We don't need to test them. If they were capable of interbreeding and were in proximity to each other, they would, and we'd find that the species had hybridised.

Compared to twiddling genes in a culture dish everything else is 'natural'. Culture and language are pretty poor at restraining the sex drive, even today.

Your last paragraph makes no sense at all. We have eyes. Fish have eyes. Does that make us the same species?


By charleski on 7/21/2013 3:25:20 AM , Rating: 2
Oh, and just so it's clear, when I say 'the species would have hybridised' I mean you'd see a mixture that's far more substantial than one gene crossing every 70 generations, which is what the results suggest happened between humans and Neanderthals.


RE: A rose by any other name is still a rose.
By croc on 7/16/2013 12:26:38 AM , Rating: 2
Ahem. 'Races' tend to not notice lines on a map. Last time I checked, Americans were not a 'race' but a nationality.


By StormyKnight on 7/16/2013 2:39:05 PM , Rating: 2
Would it have been better if he had said "ethnicities" instead of races? You got the idea. Quit nitpicking the semantics.


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