Always when ideas like these come into focus and we "begin" to understand mechanisms and histories like this, I love the new facts of course, but still suspect the full truth is a whole lot messier.
15
This is another example of the mechanistic nature of all that exists.
6
If we all originally came from Africa, why does this article mention non-African origins?
1
@Bartolo
Because homo erectus was extant throughout Asia and Europe before Neanderthals arrived. And I believe its more like 800,000 years, not 600,000. All modern humans are descendants of the San group from Botswana. Around 200,000 years ago they began migrating along the shore lines in small fishing boats. they moved up the east African shores, to India, and on to Australia/New Zealand, arriving there around 70,000 years ago. All along this migration, they left some of their people behind and these are the foundation of everyone alive today.
21
This research could explain why there is a large cohort of heterosexual, non-hemophiliac H.I.V. victims among people of sub-Saharan African ancestry but much smaller percentage among people with purely Asian or European ancestry. This is very important research.
20
@Peter Johnson
I dont't think so. Let science do scientist.
1
@Peter Johnson
Unfortunately, that "protection" is very relative, and pales in comparison to the role played by behavior, such as safe sex, treating STI, or access to treatment as prevention. That is why public health action has been able to curb the number of new HIV infections, even if much work remains to be done.
6
After reading some of these comments, I can’t help wondering about the genetic substrates that support these eager willingnesses to deny that we all came out of Africa, that our similarities are far greater than our differences, that the old racial classifications are a buncha hooey, that our languages and cultures and histories are every bit as important as our biologies.
But most of all, I’d like to know what chunks of DNA are holding up these fantasies of purity. I mean, people are reading an article that discusses among other things a significant interpolation of Neanderthal in most all of us, and discussing the mixes of backgrounds that they find when they get their gimcrack report back from “23 and Me,” and they STILL want to hang onto their precious purity.
We’re bundles, in David Hume’s sense, and have been since at least the hazy far off times when our ancestral blobs got invaded by mitochondria. Cripes, we’re actually more like coral reefs than solid blocks.
I wish we’d get over it, so we can relax a little and just look at what we are honestly.
49
"living people with non-African ancestry carry 1 percent or 2 percent Neanderthal DNA"
True, but we don't all carry the same 1 or 2%. A much larger percentage of Neanderthal DNA survives in the overall population. Since it is there, it is available to be spread if it offers advantages. Since it is still there, it must have offered some individuals some advantages in the past.
This is a large topic, potentially important, and still only touched on by what is really early work on a huge subject.
16
I took the 23andme DNA test and found I was blessed with 308 Neanderthal variants in my DNA. I can attest that there must be some truth to having an edge over the influenza virus. I've never in my 40 yrs have ever had any symptoms that others would relate to the flu and I'm sure I had to of been infected with it at some point in my life. Additionally, it maybe coincidence but my wife was diagnosed with a non clinical significant anitibody to Bg (Bennett-Goodspeed) during her first pregnancy : These are actually Human Leukocyte Antigens that cause confusing results on serological tests of erythrocytes. I would assume my daughter inherited this white blood cell antigen from me and my wife formed antibodies to it. I often wonder if this was passed down from the Neanderthals as well and may have something to do with why I rarely get ill like others to cold or flu viruses.
21
There is something odd about this article. How is it that immunity to certain diseases is encoded in DNA. Certainly this is not the case for most of us for any disease. We are not genetically immune to any disease; we have to either become immune through vaccination, or experience the disease itself and develop an immunity. It is true that certain genetic abnormalities, such as HbS which renders a partial immunity to malaria are inherited, but this is not an example of specific coded proteins which make us immune. The proteins of the viral shell are coded by the virus, not the infected cell.
5
@Honeybee
What is the basis for your belief?
Our immune systems are not primed and triggered until they are exposed to antigens. https://www.scientificamerican.com/article/your-immune-system-is-made-no...
Antibodies are passively acquired through breast milk but not inherited.
5
@Elwood
Actually, we are genetically inmune to many diseases. And there are sub-populations of humans that are currently genetically inmune to a potential pandemc that would wipe out the redt of us. Their descendants would inherit this immunity.
15
@Elwood
'How is it that immunity to certain diseases is encoded in DNA. Certainly this is not the case for most of us for any disease. We are not genetically immune to any disease...'
I think the massive die off of Native Americans after their encounters with European diseases is proof that genetics matter. They clearly did worse with measles, small pox, influenza, and other diseases. And not that these were always kind to Europeans.
Pardon my simplistic explanation but your inherited immune system's capabilities are not random or all-encompassing. They are shaped by the evolutionary history of your surviving forbears and the pathogens they encountered.
Viruses need to enter cells and take over their reproductive machinery while evading innate extracellular and intracellular defenses. Many of these are molecule to molecule interactions, and these have been shaped by evolutionary forces on both the pathogen and those infected. DNA (or RNA for some viruses) determines the makeup of the relevant protein molecules.
The immune system also has the capability to ramp up cellular defenders like T cells as well as defensive antibodies from B cells when new pathogens (or old foes) are encountered. These capabilities, in turn, also vary among individuals and are inherited.
So yes, genetics matter very much to our immunity.
7
And this is why I love science. This is soooooo cool!
44
Africans were captured, enslaved and brought to the new world precisely because they were genetically superior to Europeans. They had resistance to tropical diseases which decimated the early European imigrants.
4
@William Meyer
I don't think the science was as developed in those days.
Like most of humanity's worst actions, the enslavement of Africans was a strictly commercial enterprise.
Some things never change.
53
@William Meyer How about instead of superior to Europeans we say they had genetic qualities which made them more adaptable to the environment of South and Central America. Or are you saying Africans are better, have more intrinsic value, than Europeans?
19
@Mike
My wife and I have two daughters. They're pretty different. Neither - repeat, neither - has more intrinsic value than the other.
These two notions do not seem incompatible, and taking well-identified differences into account especially in terms of health care does not seem a crazy idea to me, as a MD and researcher.
Our ancestry determines our genetic makeup, nature our epigenetics, and this determines our health vulnerabilities to some extent. But we are social animals and what we do with all of that to try to give each and every one of us a somewhat level playing field in a larger sense is what defines a society and political system.
6
" why are those genes still there 40,000 years after Neanderthals became extinct?"
Why wouldn't they be there? Genes stay in the genome once they are inherited. That's what "junk DNA" means. Evolution weeds out genes only if they keep their possessors from reproducing.
13
@Charlesbalpha
The article didn't spend much time explaining this. I'm assuming it's the same argument as is the premise for a very interesting book, "Survival of the Sickest." The idea is that when a specific gene or mutation has stayed in the genome for thousands or millions of years, the likelihood is that it served in some way to keep the possessor of it alive at least long enough to reproduce. (Whew! Is that sentence long enough?) If for any reason it killed its "owner" off before that person could reproduce, then it's gone. And if it did nothing much, it would still tend to disappear over time, just by the law of averages.
16
"It’s likely that most Neanderthal genes were bad for our health or reduced our fertility, and therefore were lost in modern humans."
If this is true, could not the inverse also be true, that our "genes were bad for the health or reduced the fertility" of Neanderthals? Afterall, the demise of such a successful species has still not been satisfactorily explained. It seems unlikely that we did not also give the Neanderthals viruses to which they had no resistance.
90
@SC Yes, the article states just that!
3
@SC
Who is "we"?
The modern humans who evolved in Africa 300,000 years ago were not part of the European and Asian Neanderthal and Denovisan genetic clade. There is no Neanderthal nor Denovisan DNA in black Sub-Saharan African populations.
Evolutionary fitness is determined wholly by leaving the most best adapted offspring over space and time. Sub-Saharan Africans are the most ancient and genetically diverse humans. There is more genetic diversity in one Sub-Saharan African village or ethnic group than all of the rest of humanity combined.
Sub-Saharan Africa resisted European colonization and conquest for milennia via environmental factors including climate and infectious disease. See " Plagues and Peoples" by William H. McNeil
9
@SC
Mutual interactions, including the sharing of pathogens and ill fitting genes, could certainly have played a role in the demise of the Neanderthals. But they did survive for thousands of years in the same general region after first contact with modern humans. It's just as likely their reproductive rates were intrinsically lower, or their technology was inferior, or they couldn't compete with the newcomers for resources, or they were slowly exterminated in tribal warfare (apart from the occasional sexual captive).
The model of the effect of Europeans on Native Americans could be illustrative. Native American numbers were first decimated by disease but our populations (or the survivors at least) have been slowly merging since Columbus arrived. Give it 10 or 20 thousand more years and we'd be pretty homogenous.
8
For thirty years I keep hearing, there is no difference between the races and genders, everybody is the same, there is no difference between men and women. Now the Times is telling me there are fundamental differences in our DNA which effect our existence. How about we change the politically correct line. All humans have value. No one is more valuable because of their race, gender or ability to earn money. There are differences between individuals and the races or genders. Some are stronger, faster, more resistant to specific disease or specific environmental challenges. Some humans and human populations have more affinity to art, music, literature, logic and mathematics. There is variation between individuals in group populations. There is nothing wrong with everyone not being the same. In fact our differences are beautiful. I remember the chant in the 1960's, Black is Beautiful. If there really were no differences, there would be no beauty.
49
@Mike
You are confusing "sameness" with "equal rights".
Humans are all the "same" only in that we are all of the same species. Within the species, we have different genders, and different characteristics.
But in our treatment of each other, both socially and legally, we should all be fully equal in rights and in dignified treatment.
Your conflation of "sameness" and "equal rights" is a common error in logic.
35
@Mike from New York
You are not me. Your immediate family is different from my immediate family. Those are genetic differences no one has ever denied. This is true between 2 members of the same ostensible population group. Hence the true statement: you know, we all don’t look alike.
The question you bring up is whether there are meaningful differences between so called population.
The differences within a population are greater than the differences between 2 populations.
14
@JDK Possibly true that difference within a population are greater than between populations depending on how you measure differences but it would be nice if everyone could agree there are differences between populations. This might seem obvious but my experience teaching high school for 27 years tells me that the idea populations have significant differences is not universally accepted.
4
While not dismissing the effects of racism, poverty, or other sociological variables related to both spread and prevention of disease, rates of HIV and genital herpes are not equal across different regions of the US, or across different ethnic groups within the US. Neanderthal ancestry might be another previously unrecognized variable to explain this.
The Kaiser Family Foundation, cited in this article also points out that:
"Black Americans represent ...12% of the ... population (but) ...accounted for 43% of new HIV diagnoses in 2016 ... rate of new HIV diagnoses per 100,000 among Black adults/adolescents (43.6) was 8 times that of whites (5.2) and more than twice that of Latinos (17.0) in 2016.16 The rate for Black men (82.8) was the highest of any group, .... Black women (26.2) had the highest rate among women."
https://www.kff.org/hivaids/fact-sheet/black-americans-and-hivaids-the-b...
NPR has also reported on the disparity in prevalence of genital herpes (HSV2) among African-Americans:
"(the cdc)... reported that 48 percent of black women between the ages of 14 and 49 have herpes simplex virus type 2, or HSV 2 as it's called. Overall blacks and women were much more likely to be infected. The prevalence among all women was almost 21 percent compared to 11 percent for all men. Thirty nine percent of blacks were infected, compared with roughly 12 percent of whites.
https://www.npr.org/templates/story/story.php?storyId=124628530
6
@Middleman MD
This is the type of racialized conclusion I was afraid people would reach upon reading this article. Remember, the author here has a bachelor's degree in English, and is not a geneticist, so it should surprise no one that there are a number of unsubstantiated assumptions and other logical leaps in the piece-- and that's not to be offensive, it's simply a matter of truth.
Second, a good history textbook can help us appreciate that many African-Americans (the group cited in your stats, Middleman) have ancestry "outside of Africa," in large part due to the slave trade and its aftermath (the same is true of many Africans in certain parts of Africa, for that matter). So let's be careful not to jump to any conclusions by assuming genetics plays a role at all in the stats you cite.
The LGBT population is often stigmatized in similar ways. And even if it may be true that the incidence in HIV cases is still higher in the LGBT population with respect to heterosexuals, those numbers have significantly declined over the past few years, and this is not due to any genetic change in the DNA of LGBT individuals-- evolutionary change in humans is much more deliberate! I suspect, with some time, and I believe within our lifetimes, the incidence of HIV cases in those who self-identify as gay will equal that of those who self-identify as heterosexual, and genetics will have had absolutely nothing to do with that.
13
@Middleman MD
@Middleman MD
This is the type of racialized conclusion I was afraid people would reach upon reading this article. Remember, the author here has a bachelor's degree in English, and is not a geneticist, so it should surprise no one that there are a number of unsubstantiated assumptions and other logical leaps in the piece-- and that's not to be offensive, it's simply a matter of truth.
Second, a good history textbook can help us appreciate that many African-Americans (the group cited in your stats, Middleman) have ancestry "outside of Africa," in large part due to the slave trade and its aftermath (the same is true of many Africans in certain parts of Africa, for that matter). So let's be careful not to jump to any conclusions by assuming genetics plays a role at all in the stats you cite.
The LGBT population is often stigmatized in similar ways. And even if it may be true that the incidence in HIV cases is still higher in the LGBT population with respect to heterosexuals, those numbers have significantly declined over the past few years, and this is not due to any genetic change in the DNA of LGBT individuals-- evolutionary change in humans is much more deliberate! I suspect, with some time, and I believe within our lifetimes, the incidence of HIV cases in those who self-identify as gay will equal that of those who self-identify as heterosexual, and genetics will have had absolutely nothing to do with that.
3
@Middleman MD
The factors that you dismissed, are the meaningful factors that explain the statistics. Equal exposure, does lead to equal infection rates.
As a matter of fact, the only known human variation that presented the capability to go from HIV-positive to HIV-negative after exposure was found in prostitutes from Quenia.
1
Could this be why a certain percentage of Caucasians are immune to the modern HIV virus, and Africans or those of African descent whose ancestors never made contact with the Neanderthals are not?
7
@David Godinez
Possibly its a factor, but it also been theorized that the repeated plagues of the Black Death that swept Europe in the 14 century are responsible for the genetic mutation that give a few immunity to HIV.
12
@David Godinez
There is no immunity to the virus, except the example I gave above (Quenia prostitutes). Some People do not develop the symptoms, but they are soro-positive and do transmit the infection.
Beware with your statements!
5
"People of Asian and European descent — almost anyone with origins outside of Africa" - is this an alternative theory of where we ALL originated from?
6
@Robert
They phrased it wrong. All humanity originated in Africa. The Eurasians met the Neanderthals after they migrated.
10
@Robert No. We ALL originally came from Africa.
11
@Robert
"" - is this an alternative theory of where we ALL originated from? "
-------------------------------------------------------------
No.
It simply means that different groups diverged from our common ancestors at different times.
The Neanderthals diverged earlier, at around 600 thousand years ago.
7
Question 1.
Has the "delta 32" gene ever been cross indexed with the Neanderthal genome?
Question 2.
When Neanderthals were doing "the wild thing" with our great, great grandmothers why weren't they picking up some survival technology like bows and arrows?
Question 3.
October 3 was "Virus Appreciation Day" which raises the question if perhaps our ancient friends with benefits could also be recognized with a designated national day or week of recognition. October is already National Pizza Month so why not just a National Neanderthal Week?
7
@L Martin
"why weren't they picking up some survival technology like bows and arrows?"
Maybe they did. We don't know why they died out. Perhaps an epidemic to which our ancestors were immune. It may have had nothing to do with "bows and arrows".
13
@L Martin: Are you sure the Neanderthals women weren't doing the wild thing with the modern men? What is the evidence from the Y chromosome and the mitochondrial DNA?
If the sociological pattern is any indicator, the males from the dominant group would have enjoyed the 'favors' from the females of the other group, unless they were matriarchal, in which case that might be reversed. Given that the Neanderthals were extinct, you might guess that the moderns were the dominant group, although this is by no means a given.
I've never seen a study that uses the Y chromosome or the mitochondrial DNA to address these issues.
8
another poem,
Once I was young --
yesterday, perhaps --
danced with RNA and DNA
And kissed some other chaps.
Once I was young,
but never was naive.
I thought I had a gamete or two
Up my imaginary sleeve.
And now I know I was naive.
I didn't know what DNA was
you took my hand
Then mtdna it was
And I'll say it was grand
Grand to be alive, to be young
To be mad, to be yours alone
grand to take your hand in my hand
and to know that you're not a clone
I didn't know what DNA was
then I met you.
Oh, mtDNA it was,
How sublime it was too!
I didn't know what DNA was
You held my hand.
Warmer than RNA it was,
And I'll say it was grand.
Grand to be alive, to be young,
To be mad, to be yours alone!
Grand to see your face, feel your touch,
Hear your voice say, "I'm not a clone."
I didn't know what DNA was
Life was unreal.
I wanted love and here it was,
Not just another allele.
I'm wise,
And I know what DNA is now.
20
@aaron ginsburg
Move over Rogers & Hart.....
2
Just read “Sapiens - A brief history of humankind" by Yuval Noah Harari
A very compelling book that I would like to recommend
13
The article should not say, "modern humans encountered new viruses ... as they expanded out of Africa roughly 70,000 years ago". What would be correct is, "a significant share of modern humans encountered new viruses ... as they expanded out of Africa roughly 70,000 years ago". Human modernity did not result from, or go together with, humans leaving Africa.
20
"The researchers pored through the genomes of living Asians and Europeans, and discovered a large fraction of those Neanderthal genes make proteins that interact with viruses."
what about living (native) americans? about 500 years ago there was another migration and continent-wide viral and bacterial infections.
see also, australia, japan and various islands.
one paper at a time...
5
Those alpha genes vs our technology powered lifestyles...
Well more than "anything but the result of our past".
but we should not forget our past.
1
If Neanderthals themselves came from Africa through common ancestors surely modern humans who came later in a second wave would have the same genetic make up with improved versions to cope with ecological changes over time.The original useful information would have already been retained in their cells.So how can we argue that interbreeding later on between the two resulted in retention of useful genes which withstood the test of time.
3
@M.T.Hasan: Your question contains flawed logic. You ask:
"....surely modern humans who came later in a second wave would have the same genetic makeup with improved versions (of DNA)."
This is erroneous thinking. Don't conflate "modern human" with some form of genetic superiority. There's no such thing in genetics. How would their genetic makeup be improved if they've never encountered the various diseases long dealt with by the Neanderthal's in the first place, eh? They'd have no immunity. They'd be a free lunch to those diseases.
Think of it as an inversion of what occurred when Europeans invaded the Americas, and in so doing bringing a host of diseases never before encountered by the native Indians. Without a mechanism by which genetic immunity to endemic diseases could occur, in this case interbreeding, one population would wipe out the other. As was the case in the America's.
Indeed, those American Indians who interbred with Europeans insured the survival of their peoples. It's the way Nature, all bloody red in tooth and claw, works. So we of European descent should thank our Neanderthal ancestors. They enhanced our survival, unfortunately at the cost to themselves...
John~
American Net'Zen
39
@M.T.Hasan
Because in between the first and second waves the two populations were whittled down and each selected genes and mutations useful to deal with their specific environments.
4
Is there any evidence that modern humans with Neanderthal background have more of a defense against modern HIV or Influenza than do modern humans who have no Neanderthal background?
17
@MKV
Well, HIV arose, I believe in Africa; and HIV is now most prevalent in Africa. Not at all sure that is relevant evidence, for other explanations come to mind, but there it is.
2
@Dennis Galon
Actually current research points out that the virus jumped species from our primate cousins to us, probably in the Caribbean region, not in Africa.
2
@MKV
Scandinavians are known to more frequently carry a CCR5-delta 32 mutation conferring (relative) resistance to HIV infection.
https://www.nature.com/scitable/blog/viruses101/hiv_resistant_mutation?i...
With influenza - a more ancient and more highly transmissible disease - it's more complicated.
4
This reminds me of a poem I wrote in 1998:
The Medicine Man Speaks on Evolution
His story begins in his illness,
when his body found no friends
in the village where we live,
the women looking at him with stone stares,
saving their smiles for the buds on trees and dead rock.
Needing to join with something, with anything,
the cells in his body took in the homeless beings
that float in the air, swim in the water, and fight in the earth,
they gave them shelter, fed them, created important work for each of them
(though it seemed as if his fevered body was at war),
and called them mit-o-chon-dri-a.
And he, who was once one with us,
became something more than a man, but less than a spirit,
and when the children began to die in droves,
it was to him the women came,
to beg him for a drop of his blood
to cook in the soup that would save their sons and daughters.
Brandywine
4/14/98
http://home.bway.net/hchang/medicine.html
15
So did modern humans bring with them viruses or genes that contributed to the extinction of Neanderthals?
43
So Neanderthal was not just a brute as sometimes characterized. Neanderthal endowed present day humans with the ability to defend against diseases Neanderthal apparently had( but not so HIV). This revelation, "sword and shield" as the article put it, is quite remarkable. I see other commentators wish to give this bit of science a political spin. Science does not need the spin.
22
It seems that the transformation of the Neanderthal as brute occurred once scientists surmised that only Europeans and Asians had their genes. Then, they went in search of the “positive” contributions of those genes. Before that, it was pure “uga uga”. Funny how that works...
5
@Plum
Actually geneticists do not corroborate with the "Uga Uga" or claims of superiority, that comes from movies or white supremacist propaganda. Every species adapts to their environment. We are modifying our world environment with global warming.
Good luck evolving!
6
@Bian
No, science does not need the spin.
You can be a brute AND have relative protection against some disease, because those who were more vulnerable died more and earlier than others.
3
To contemplate an ancestral connection to beings living on Earth 600,000 years ago is at oncer humbling and transcendent.
Thank you.
70
@dmbones
So far as is known, we have an ancestral connection to all life on earth, whether living now or at any time in the past.
11
So much for statutes of limitation.
11
You can also read 50 000bc on the brink of extinction
2
The Book of Genesis is clear as to Who created Man. Thank you.
2
@Southern Boy, I prefer my scientific reference text to be a little more rigorous than the Old Testament. Not lakying any blame here - I'm not sure if Moses knew about peer review....
14
@Southern Boy Wrong and sad. I will say that Gen 3 may have captured the interbreeding story as it is a story about sex. God forbids sex with the other, but Eve and Adam persist and end up having sex with the ole serpent. Cain is the offspring of that union, while Abel was the offspring of Adam and Eve.
One of the more likely places for Neanderthals and modern humans to interact is in Middle East.
The Embellished Oral History of the Jews is not a Religious Text, but a good document when interpreted correctly.
4
@Ant'ney
Actually, Evolution is well described in Genesis, you just need to know how to read the meaning through the words
fishes (all life started in water)
Plants (very likely the first species out of water)
animals (everyone but us)
Men (and women, still evolving...)
1
I’m kinda hairy and I NEVER get sick.
69
@New World
Thank you for the chuckle.
Comments in NYT are superior to many newspapers, and that can largely be attributed to a propensity towards seriousness.
Ergo, one-liner humor is a treasure to readers.
31
Hmmm. Through a commercial genetic test, I learned I have more Neanderthal alleles than 94% of the population. This article seems to provide an explanation for why I never seem to get sick. Few colds. No flu, No viruses -- even when directly exposed (mono, for instance). While I'll still get my flu shot this winter, I'll take some comfort in knowing I have extra protection from the vestiges of my Neanderthal heritage.
31
My genetic test revealed the exact same results and I am rarely sick as well, a cold every few years and rarely the flu. I also have contracted herpes unfortunately from my youth but after being diagnosed more than a decade ago have had maybe 4 outbreaks, much to the confusion of my doctors. Looks like the Neandertal genes are still influencing my health in dramatic ways.
8
@Unabashed Dem
I have more Neanderthal variants (312) than 94% of the people tested by 23AndMe. The last time I was infected by anything noticeable was over a decade ago after I visited a brother in a VA hospital.
3
On one hand I appreciate people being interested in science; on the other this highlights the problem I have with non-academic science writing (I also have a problem with academic writing but making a point here..) People tend to make massive conclusive leaps based on their own experiences.
I (mixed race) have less neanderthal DNA than 98% of the population, but I never get sick. My (white) roommate back in college, may have neanderthal DNA and was sick at least once a month. I never caught anything from her after years of living together... so any jump to ‘whites and asians may get less infected than blacks because of their better DNA’ is CRAZY and is the kind of racial hand waving we do not need right now. it’s totally untrue. also dangerous are comments conflating this with the reason why HIV is prevalent in the AA population. that’s VERY untrue as well.
The article is trying to make something that is only slightly interesting sexy—“Neanderthal DNA looks to have some mildly beneficial protein function. (particularly, we forcibly associated them with viruses worthy of research dollars..)”
But you have hundreds of thousands of beneficial proteins in your body from countless different environmental encounters. viruses have also been interacting with proteins for eons. The real headline should be: “a tiny sliver of our dna was never thrown out by evolution because it didn’t do enough harm. we’re finding out there’s a chance it’s not totally worthless to have.”
9
Is it possible that the germs that the modern humans brought with them out of African infected and perhaps contributed to the extinction of the Neanderthals?
23
@Joel
Neanderthals had thicker bodies and greater mass most likely to cope with cold winters during the ice ages.
When the ice melted Neanderthals had more trouble finding game that moved further and further as the glaciers receded.
It's likely the newcomers killed some Neanderthals as well but most likely Neanderthals couldn't adapt to the changes in the climate while the newcomers had better skills for doing so and they could always wear thicker clothing when it was cold.
It's an ecological principle that mammals get bigger the closer to the poles one goes since big bodies hold onto heat better than skinny ones but big bodies overheat quicker than smaller, skinnier ones. It's likely they couldn't evolve fast enough so they died out.
1
@lightscientist66
So that means that "fat" people have more Neanderthal genes?
2
The Neanderthals were human just like us. If you embrace the belief that Neanderthals were not Homo sapiens,you have a big problem,because one of the arguments in deciding species is the ability to interbreed and produce offspring who are fertile over many generations. Which obviously must have occurred.
On a non-scientific philosophical basis I often fall back on the Cain and Able story. Fratricide.
13
@ wy4ridem Given what we've seen in our species, it's not hard to see what we might have pulled on our earlier cousins occupying the lands we wanted.
10
@ wy4ridem Many species (as currently classified) can hybridize and produce fertile offspring. For example most (all?) species in the genus Canis can easily produce fertile hybrids. And two species of guenon have been happily producing fertile hybrids for ages...
https://www.the-scientist.com/news-opinion/monkey-hybrids-challenge-assu...
2
@ wy4ridem
Given interbreeding, we have, it seems to me, three choices:
We could stick with our notion that sexual infertility defines species differentiation, and follow your lead by redefining Neanderthals (and Denisovans) as simply variations of Homo sapiens.
We could reject the definition of species as always based on productive sex, in order to continue to distinguish Homo Sapiens vs Homo Neanderthalensis vs Homo Denisova
Or we could speak of: Homo Sapiens Sapiens vs. Homo Sapiens Neanderthalensis vs Homo Sapiens Denisova.
This is not my field, but I sense a movement towards the third option.
11
Well it seems as if the "modern" humans may have survived the onslaught of diseases that could have exterminated us.
I use the discovery of North & South America by Europeans that brought along their petulance and diseases effectively annihilating so much of the native population.
The struggle to eradicate or control virulent diseases (HIV, etc.) continues but given our present knowledge, we hopefully can learn to control the DNA that impacts our health. Now if only we can keep the corporate world from trying to make vast amounts of wealth from the ability to control such diseases.
19
@Gene Sorry, but it is not so much the wealth that capitalism generates in the hearts of some people, but the maladies their foolishness might develop.
1
"But OUR extinct relatives also gave US genetic defenses." The assumption underlying this statement is one that pervaded so many of the instructional classroom documentaries I sat through as a child in the 1980s: "our Western heritage," "nos ancetres, les gaulois," the list cannot be exhausted. I wonder if Mr. Zimmer is aware that some of US don't fall into his exclusive definition of US, which he limits to "almost anyone with origins outside of Africa." While I cannot rebut the science that might support his conclusions-- I'm a lawyer, not a geneticist-- I know I'm capable of reading an article in the New York Times, and it would be nice if HE? and others who make similar assumptions, would count people like ME among his readership, even if WE may have inferior mechanisms to ward off disease! Merci!
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I had the same thought, but could never have put it so well.
There are so many times when we read other articles that any things like “when humans left Africa thousands of years ago” etc. How difficult is it so say “when SOME humans left...”? He “some” or “many” really makes a difference.
When articles miss these little bits of nuanced language, it leaves the door open for problems.
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@James
My first thought after "But OUR extinct relatives also gave US genetic defenses", was " We gave you our genes ,you gave us genocide (extinction actually.)
Not sure the gene exchange was even consensual for that matter. You know how that works...
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@James
The Africa reference only is only related to human cross-migration. Neanderthal genes are only present in populations who descend from humans mixing with Neanderthals (40000 to 60000 years ago).
DNA evidence shows that these ancient populations never migrated back to sub-Saharan Africa.
People with Neanderthal DNA are not an exclusive and illustrious group. They are not better than modern or ancient Africans. This science is in it's infancy and there is much to discover. I know all this, in part, because of books and articles that Mr Zimmer has written.
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