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Angela
15-02-16, 18:52
See:
http://science.sciencemag.org/content/351/6274/737

This is yet another paper that explores the impact of Neanderthal introgression on disease risk. It confirms the association with What is really new and useful for the general reader is that they provide the specific snps involved, meaning we can look them up, at 23andme, for example, if we've been tested there.


"Neandertal SNPs explained a significant [likelihood ratio test; false discovery rate (FDR) < 0.05 over all phenotype tests] percent of the risk in three traits in the E1 discovery cohort (Table 1 (http://science.sciencemag.org/content/351/6274/737.full#T1)): depression (2.03%, P = 0.0036), myocardial infarction (1.39%, P = 0.0026), and corns and callosities (1.26%, P = 0.01). Neandertal SNPs also explained a nominally significant (P < 0.1) percent of risk for nine additional traits, including actinic and seborrheic keratosis, coronary atherosclerosis, and obesity."

One of the nine not mentioned in this quote is rheumatolgical disorders including rhematoid arthritis. No wonder poor Otzi had arterio-schlerosis.



"We also tested whether the percent of phenotypic variance explained by Neandertal SNPs remained significant in the context of non-Neandertal SNPs by including an additional genetic relationship matrix (GRM) computed from non-Neandertal SNPs across the rest of the human genome in the mixed linear model (11 (http://science.sciencemag.org/content/351/6274/737.full#ref-11)). Depression (P = 0.031), mood disorders (P = 0.029), and actinic keratosis (P = 0.036) were replicated with these stricter criteria in the independent E2 cohort."

By mood disorders they mean bi-polar disorder.


I found this interesting as well:
"Depression risk in modern human populations is influenced by sunlight exposure (18 (http://science.sciencemag.org/content/351/6274/737.full#ref-18)), which differs between high and low latitudes, and we found enrichment of circadian clock genes near the Neandertal alleles that contribute most to this association."


Anyway, as to the specific snps involved:
"The strongest signal was a Neandertal SNP (rs3917862, 6.5% European (EUR) 1KG frequency) in an intro"n of P-selectin (SELP) that was significantly associated with hypercoagulable state in both E1 and E2."

Clearly, the blood coagulating quickly means you're less likely to die from a wound. There are other consequences that aren't so great.

"The second replicating association was a SNP (rs12049593, 5.0% EUR frequency) in an intron of SLC35F3, a putative thiamine transporter, which associates with protein-calorie malnutrition. Thiamine is crucial to carbohydrate metabolism for all cells, particularly those with increased energy requirements (23 (http://science.sciencemag.org/content/351/6274/737.full#ref-23)). Decreased expression of this transporter in the brain or GI tract could exacerbate malnutrition or its symptoms. It is possible that new dietary pressures may have caused changes in carbohydrate metabolism to be beneficial in early human migrants out of Africa; indeed, there is evidence suggesting that Neandertal introgression probably influenced lipid catabolism in Europeans (9 (http://science.sciencemag.org/content/351/6274/737.full#ref-9)). More recently, the reduction of thiamine present in foods from the grain-refining process, as well as an increased intake of simple carbohydrates, make this a potentially harmful allele, because it could reduce thiamine availability although modern diets increase demand."

That one I don't quite understand.



"Another Neandertal SNP (rs11030043, 9.0% EUR frequency) is upstream of stromal interaction molecule 1 (STIM1) and is associated with a phenotype encompassing incontinence, bladder pain, and urinary tract disorders,"


"The last replicated association was between rs901033 (0.5% EUR frequency) and tobacco use disorder. This SNP is in an intron of SLC6A11, a solute carrier family neurotransmitter transporter that is responsible for reuptake of the neurotransmitter γ-aminobutyric acid (GABA). Nicotine addiction disrupts GABAergic signaling in the brain and reduces expression of SLC6A11 (25 (http://science.sciencemag.org/content/351/6274/737.full#ref-25)). This is the second Neandertal SNP to be associated with smoking risk (5 (http://science.sciencemag.org/content/351/6274/737.full#ref-5)). The last replicated association was between rs901033 (0.5% EUR frequency) and tobacco use disorder. This SNP is in an intron of SLC6A11, a solute carrier family neurotransmitter transporter that is responsible for reuptake of the neurotransmitter γ-aminobutyric acid (GABA). Nicotine addiction disrupts GABAergic signaling in the brain and reduces expression of SLC6A11 (25 (http://science.sciencemag.org/content/351/6274/737.full#ref-25)). This is the second Neandertal SNP to be associated with smoking risk (5 (http://science.sciencemag.org/content/351/6274/737.full#ref-5))."


Rheumatoid Arthritis and other related polyarthritis conditions. Rs12639456

Tomenable
16-02-16, 21:26
Were any of the intelligence-increasing SNPs (see the studies linked below) also inherited from Neanderthals ???:

Piffer 2013 - http://emilkirkegaard.dk/en/wp-content/upl...ment-and-IQ.pdf (http://emilkirkegaard.dk/en/wp-content/uploads/Factor-Analysis-of-Population-Allele-Frequencies-as-a-Simple-Novel-Method-of-Detecting-Signals-of-Recent-Polygenic-Selection-The-Example-of-Educational-Attainment-and-IQ.pdf)
Piffer 2014 - http://www.ibc7.org/article/journal_v.php?sid=317
Piffer & Kirkegaard - http://openpsych.net/OBG/2014/04/the-genet...nitive-ability/ (http://openpsych.net/OBG/2014/04/the-genetic-correlation-between-educational-attainment-intracranial-volume-and-iq-is-due-to-recent-polygenic-selection-on-general-cognitive-ability/)
Rietveld 2013 (https://www.sciencemag.org/content/340/6139/1467.abstract) - http://scholar.harvard.edu/files/laibson/f...ence_053013.pdf (http://scholar.harvard.edu/files/laibson/files/gwas_science_053013.pdf)
Benyamin 2013 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3935975/
Gosso 2007 - http://www.biomedcentral.com/1471-2350/8/66

At least 14 SNPs correlated with intelligence (of them at least 10 positively and at least 1 negatively) have been identified.

That allele which is associated with lower cognitive ability (lower intelligence and lower educational attainment), Rs429358(C) - is carried by ca. 26% of Sub-Saharans, ca. 14% of Europeans, ca. 11% of Native Americans and by around 9% of East Asians.

By contrast, combined frequencies of 10 SNPs associated with higher cognitive ability are higher in Eurasian populations.

We share one of these 10 alleles with other primates, but the remaining 9 are unique to the genus Homo:


(...) Nine of the 10 alleles associated with educational attainment were derived, thus unique to humans and not shared with non-human primates. This result was significant (p=0.01) and is predicted on the basis of the assumption that humans have evolved by natural selection to become more intelligent than their primate cousins. The results show that this evolutionary process, which was already far advanced at the time when modern humans spread across the globe approximately 65,000 years before present, has continued in modern human populations after that time. It invalidates theories that assume, explicitly or implicitly, that human cognitive evolution has ended with the first appearance of physically modern Homo sapiens (e.g., Tooby and Cosmides, 1992). (...)

In particular one intelligence-boosting allele - Rs13188378(G) - appears to be absent from Sub-Saharans, but is present in Europeans, Asians and Native Americans. So I suppose, that it is possible that Eurasians inherited this SNP from Neanderthals.

Angela
16-02-16, 22:41
This study doesn't discuss it, but to the best of my recollection prior studies have found, on the contrary, that Neanderthal introgression leads to cognitive and language processing difficulties, i.e. lower verbal IQ, perhaps dyslexia, perhaps a higher risk of autism.

I wouldn't give too much weight to a couple of genes for intelligence. Over one hundred separate genes are involved in differences in height; only imagine how many are involved in intelligence, which is vastly more complex.

Tomenable
16-02-16, 23:23
prior studies have found, on the contrary, that Neanderthal introgression leads to cognitive and language processing difficulties, i.e. lower verbal IQ, perhaps dyslexia, perhaps a higher risk of autism.

There was nothing about cognitive processing difficulties there, only about speech production, IIRC.

That could be all down just to anatomical issues (different speech mechanism), not related to brain:

http://image.slidesharecdn.com/effectivespeechandoralcommunication-150615012407-lva1-app6892/95/effective-speech-and-oral-communication-29-638.jpg?cb=1434331640


perhaps a higher risk of autism.

Quite possible. But read this:

"Autism Genes Linked To Higher Intelligence: Treading A Fine Line Between Intellectual Disability And Superiority":

http://www.medicaldaily.com/autism-genes-linked-higher-intelligence-treading-fine-line-between-intellectual-325798

"Autism IS linked to higher intelligence: People with genes related to the condition 'scored better in mental ability tests'


People carrying autism genes scored better on intelligent tests
Genetic factors in autism associated with heightened mental ability" :

http://www.dailymail.co.uk/health/article-2988410/Autism-linked-higher-intelligence-People-genes-related-condition-scored-better-mental-ability-tests.html

Promenade
17-02-16, 17:18
See:
http://science.sciencemag.org/content/351/6274/737

This is yet another paper that explores the impact of Neanderthal introgression on disease risk. It confirms the association with What is really new and useful for the general reader is that they provide the specific snps involved, meaning we can look them up, at 23andme, for example, if we've been tested there.


"Neandertal SNPs explained a significant [likelihood ratio test; false discovery rate (FDR) < 0.05 over all phenotype tests] percent of the risk in three traits in the E1 discovery cohort (Table 1 (http://science.sciencemag.org/content/351/6274/737.full#T1)): depression (2.03%, P = 0.0036), myocardial infarction (1.39%, P = 0.0026), and corns and callosities (1.26%, P = 0.01). Neandertal SNPs also explained a nominally significant (P < 0.1) percent of risk for nine additional traits, including actinic and seborrheic keratosis, coronary atherosclerosis, and obesity."

One of the nine not mentioned in this quote is rheumatolgical disorders including rhematoid arthritis. No wonder poor Otzi had arterio-schlerosis.



"We also tested whether the percent of phenotypic variance explained by Neandertal SNPs remained significant in the context of non-Neandertal SNPs by including an additional genetic relationship matrix (GRM) computed from non-Neandertal SNPs across the rest of the human genome in the mixed linear model (11 (http://science.sciencemag.org/content/351/6274/737.full#ref-11)). Depression (P = 0.031), mood disorders (P = 0.029), and actinic keratosis (P = 0.036) were replicated with these stricter criteria in the independent E2 cohort."

By mood disorders they mean bi-polar disorder.


I found this interesting as well:
"Depression risk in modern human populations is influenced by sunlight exposure (18 (http://science.sciencemag.org/content/351/6274/737.full#ref-18)), which differs between high and low latitudes, and we found enrichment of circadian clock genes near the Neandertal alleles that contribute most to this association."


Anyway, as to the specific snps involved:
"The strongest signal was a Neandertal SNP (rs3917862, 6.5% European (EUR) 1KG frequency) in an intro"n of P-selectin (SELP) that was significantly associated with hypercoagulable state in both E1 and E2."

Clearly, the blood coagulating quickly means you're less likely to die from a wound. There are other consequences that aren't so great.

"The second replicating association was a SNP (rs12049593, 5.0% EUR frequency) in an intron of SLC35F3, a putative thiamine transporter, which associates with protein-calorie malnutrition. Thiamine is crucial to carbohydrate metabolism for all cells, particularly those with increased energy requirements (23 (http://science.sciencemag.org/content/351/6274/737.full#ref-23)). Decreased expression of this transporter in the brain or GI tract could exacerbate malnutrition or its symptoms. It is possible that new dietary pressures may have caused changes in carbohydrate metabolism to be beneficial in early human migrants out of Africa; indeed, there is evidence suggesting that Neandertal introgression probably influenced lipid catabolism in Europeans (9 (http://science.sciencemag.org/content/351/6274/737.full#ref-9)). More recently, the reduction of thiamine present in foods from the grain-refining process, as well as an increased intake of simple carbohydrates, make this a potentially harmful allele, because it could reduce thiamine availability although modern diets increase demand."

That one I don't quite understand.



"Another Neandertal SNP (rs11030043, 9.0% EUR frequency) is upstream of stromal interaction molecule 1 (STIM1) and is associated with a phenotype encompassing incontinence, bladder pain, and urinary tract disorders,"


"The last replicated association was between rs901033 (0.5% EUR frequency) and tobacco use disorder. This SNP is in an intron of SLC6A11, a solute carrier family neurotransmitter transporter that is responsible for reuptake of the neurotransmitter γ-aminobutyric acid (GABA). Nicotine addiction disrupts GABAergic signaling in the brain and reduces expression of SLC6A11 (25 (http://science.sciencemag.org/content/351/6274/737.full#ref-25)). This is the second Neandertal SNP to be associated with smoking risk (5 (http://science.sciencemag.org/content/351/6274/737.full#ref-5)). The last replicated association was between rs901033 (0.5% EUR frequency) and tobacco use disorder. This SNP is in an intron of SLC6A11, a solute carrier family neurotransmitter transporter that is responsible for reuptake of the neurotransmitter γ-aminobutyric acid (GABA). Nicotine addiction disrupts GABAergic signaling in the brain and reduces expression of SLC6A11 (25 (http://science.sciencemag.org/content/351/6274/737.full#ref-25)). This is the second Neandertal SNP to be associated with smoking risk (5 (http://science.sciencemag.org/content/351/6274/737.full#ref-5))."


Rheumatoid Arthritis and other related polyarthritis conditions. Rs12639456

It makes me wonder why we carry so much of their genome if it has such negative consequences. Surely there was some kind of benefit from this introgression? Possibly these genes once held or still hold a purpose we arent noticing, like as Tomenable mentioned autism being linked to higher intelligence in some cases

Angela
17-02-16, 17:31
There was nothing about cognitive processing difficulties there, only about speech production, IIRC.

That could be all down just to anatomical issues (different speech mechanism), not related to brain:

http://image.slidesharecdn.com/effectivespeechandoralcommunication-150615012407-lva1-app6892/95/effective-speech-and-oral-communication-29-638.jpg?cb=1434331640



Quite possible. But read this:

"Autism Genes Linked To Higher Intelligence: Treading A Fine Line Between Intellectual Disability And Superiority":

http://www.medicaldaily.com/autism-genes-linked-higher-intelligence-treading-fine-line-between-intellectual-325798

"Autism IS linked to higher intelligence: People with genes related to the condition 'scored better in mental ability tests'


People carrying autism genes scored better on intelligent tests
Genetic factors in autism associated with heightened mental ability" :

http://www.dailymail.co.uk/health/article-2988410/Autism-linked-higher-intelligence-People-genes-related-condition-scored-better-mental-ability-tests.html

Yes, well, tell that to the parents of children with autism. I know quite a few families in this situation and I wouldn't wish it on my worst enemy. Their poor children are locked in their own skins. Better to have a Down Syndrome child. For every semi-functioning autistic person there are God knows how many that will be incapable of leading really independent lives. These parents live in dread of their own deaths because it will leave their children vulnerable. If there's an after life they should go straight to paradise, because they've already lived a hell on earth.

Even dealing with children with ADHD is more challenging than most parents can handle well.

I wasn't talking about physical differences; I was talking about neural pathways in the brain.
"There are gene deserts in which you find very few Neanderthal alleles, presumably because those alleles didn’t work well in modern humans. There is a dearth of testes-associated gene, not too surprising because they evolve particularly rapidly and are therefore more likely than average to be incompatible with a sister group that diverged some time ago. The area around FOXP2 is such a desert: Neanderthals were perhaps worse at speech, or any rate different in some way that didn’t mesh."
https://westhunt.wordpress.com/2014/01/30/adaptive-neanderthal-admixture/

See also:
http://www.biolinguistics.eu/index.php/biolinguistics/article/viewFile/304/305

There are numerous papers on the subject.
https://evolution-institute.org/blog/how-admixture-with-neanderthals-may-have-affected-human-populations/

LeBrok
17-02-16, 18:37
It is hard to say how good Neanderthal genome was for humans. Most of information about known Neanderthal genes come for hospital databases. Databases full of diseases related info. So for now all information we have is about how bad it is for us.

Tomenable
17-02-16, 20:13
Yes, well, tell that to the parents of children with autism. I know quite a few families in this situation and I wouldn't wish it on my worst enemy. Their poor children are locked in their own skins.

Probably (like with many similar traits) homozygous = higher intelligence + autism, while heterozygous = only higher intelligence.

Thus the mutation is beneficial but only as long as you have just one derived allele. When you have both, you get autism.

Just my guess.

Tomenable
17-02-16, 20:26
Surely there was some kind of benefit from this introgression?

Apparently some recessive Neanderthal mutations tend to mask (= neutralize the negative effects of) our own, indigenous human, deleterious mutations. Acquiring their imperfections helped us neutralize our own (pre-Neanderthal admixture) imperfections.

Quote:

http://biorxiv.org/content/early/2015/10/31/030387

"We also show that if deleterious mutations are recessive, the Neanderthal admixture fraction would gradually increase over time due to selection for Neanderthal haplotypes that mask human deleterious mutations in the heterozygous state. This effect of dominance heterosis might partially explain why adaptive introgression appears to be widespread in nature."

Heterosis = so called hybrid vigor.

Maybe this explains, why humans for the first time achieved technological superiority over Neanderthals only during the Aurignacian culture, which - as recent genetic studies show - was not really 100% human, but 90% Human and 10% Neanderthal. See Oase1 genome - he was one of Aurignacians, and he had ca. 9% recent Neanderthal ancestry - one or two Neanderthal great-great-grandparent(s). Before the Aurignacian period, human tools were not more complex or in any other way superior to Neanderthal tools. Only in Aurignacian findings archaeologists started to observe a higher level of technology than in either 100% Neanderthal or 100% Human cultures.

Perhaps autism comes from Neanderthals and in the heterozygous state it only boosts intelligence, without causing the disease.

This is also the case with sickle-cell anaemia (in the heterozygous state this mutation only makes you immune to malaria, but in the homozygous state in addition to making you immune to malaria, it also causes sickle-cell anaemia - a deadly disease).

As ironic as it is, many mutations are beneficial in the heterozygous state, but become deleterious in the homozygous state.

Tomenable
17-02-16, 20:44
What about the case of Ashkenazi Jews?

They have a heavy genetic burden / high frequencies of heritable diseases, but also very high intelligence. Aren't the two things (diseases and high IQ) actually caused by the very same mutations (but associated diseases appear only in the homozygous state)?

I know that most explanations say that these two Ashkenazi peculiarities are unrelated (and that diseases were caused by population bottlenecks and inbreeding, while high IQ was caused by selective pressure pushing Jews into white-collar occupations in Medieval Europe). But maybe they are actually related, and the same derived alleles which cause diseases, also cause intelligence boosts?


I wasn't talking about physical differences; I was talking about neural pathways in the brain.

"There are gene deserts in which you find very few Neanderthal alleles, presumably because those alleles didn’t work well in modern humans. There is a dearth of testes-associated gene, not too surprising because they evolve particularly rapidly and are therefore more likely than average to be incompatible with a sister group that diverged some time ago. The area around FOXP2 is such a desert: Neanderthals were perhaps worse at speech, or any rate different in some way that didn’t mesh."

Yes, they were definitely different.

But as far as I know, Neanderthals were really not imbeciles. If technological advancement can be used as some kind of measure of intellect, then they were intellectually on par with AMH (anatomically modern humans) for a long time.

Neanderthal Mousterian culture was not really inferior to AMH cultures existing at the same time (according to James Shreeve, "The Neandertal Enigma"). They were also not superior. Maybe in some fields less advanced, in some more.

Aurignacian culture became more advanced than Neanderthal cultures (which continued to exist as neighbours of Aurignacians).

However, now we know, that Aurignacians were not pure humans, but had some Neanderthal admixture.

I'm not saying that it was absorption of Neanderthal genes which made Aurignacian technology superior.

It could be down to purely cultural exchange (maybe Neanderthals had some inventions, that humans didn't have, and vice versa - and when mixing, they exchanged their knowledge, forming a technologically superior material culture).

Angela
19-02-16, 16:41
@LeBrok,
Actually, most of the studies are done using standard data bases like 1000 Genomes. The most important fact is that there are no or few Neanderthal genes in certain areas, including cognitive areas involving speech, for example, suggesting those alleles have been purged by selection. They are also looking at the ones which remain; a good number of these have disease risk associations. While these particular alleles might have conferred, and still do confer a benefit, the benefit, as is often the case, is accompanied by a detriment. A simple example is light skin mutations in humans. They may confer a benefit in that they allow more absorption of Vitamin D from the sun. The detriment is a higher risk for skin cancer in certain climates.

Also, as the latest paper on Neanderthal introgression suggests, it's not a question solely of Neanderthal dna being problematic for AMHs but of the reverse as well.

@Tomenable,
Who said that autistic people are intelligent? I don't know if they have special education classes or sections in your schools. We do have them, and I also know quite a few people with autistic children. There's no way anyone could possibly tell if these children are intelligent or not because a lot of them can't even speak, or do so haltingly. How could their verbal IQ or any other measure of intelligence be measured? You may be thinking about people who have been diagnosed as having Asberger's. Maybe you might call that being on the autism scale, but actually autistic people are a different matter. As to any supposed benefits for heterozygozity they can't even pinpoint the relevant genes yet so how can anyone possibly know if being heterozygous for whatever it is would be a benefit?

As for intelligence in endogamous societies, I think it all depends on the set of genes in the founding population, and then selective pressures acting on that. The mutations for good or bad first have to exist, although of course detrimental mutations might pop up later. Then it becomes a question as to what they are and whether they prevent procreation. So, selection again. Sometimes the selection is social, not just natural. If you are part of a society where you can't become a male adult and marry unless you can read Hebrew at your Bar Mitzvah, boys with severe learning issues or disabilities aren't going to have offspring.

Likewise, in certain farming cultures where only one son inherits the free hold or gets the lease from the landlord, the land isn't going to go to a man who can't farm it. In such situations, younger sons who were intelligent went into the church, and perhaps a few into the army. The less capable in every way remained as unpaid labor on the sibling's farm and never married. Life was harsh in those days.

Tomenable
21-02-16, 18:03
Sometimes the selection is social, not just natural.

Here a very interesting 2014 article about this by Nicholas Wade:

http://time.com/91081/what-science-says-about-race-and-genetics/

Angela
21-02-16, 19:15
Here a very interesting 2014 article about this by Nicholas Wade:

http://time.com/91081/what-science-says-about-race-and-genetics/

I very much agree with almost everything he says. However, in modern western societies with very progressive welfare benefits even people who are not really adapted to the modern economy can and do procreate, and sometimes at higher levels than the more educated. As a larger and larger share of the population is incapable of attaining the skills necessary to thrive in modern society but do have children (also so incapable), we have multiple generations of people who wind up depending on social assistance. This kind of income inequality is bound to spell trouble.

Btw, I noticed he agrees with some of the arguments that were made on this site about the fact that adaptation to a farming lifestyle required and selected for certain traits. LeBroc and I could have used the appeal to authority, but we, or at least I, didn't know Wade had made this argument. I just thought we were particularly insightful. :)

"Human social structures change so slowly and with such difficulty as to suggest an evolutionary influence at work. Modern humans lived for 185,000 years as hunters and gatherers before settling down in fixed communities. Putting a roof over one’s head and being able to own more than one could carry might seem an obvious move. The fact that it took so long suggests that a genetic change in human social behavior was required and took many generations to evolve."

The traits favored by selection in an agrarian world also proved beneficial in trade and industrialization.

"Turning up punctually for work every day and enduring eight eight hours or more of repetitive labor is far from being a natural human behavior. Hunter-gatherers do not willingly embrace such occupations, but agrarian societies from their beginning demanded the discipline to labor in the fields and to plant and harvest at the correct times. Disciplined behaviors were probably evolving gradually within the agrarian English population for many centuries before 1200, the point at which they can be documented."

Tomenable
21-02-16, 20:14
Here also an interesting article - disparate rates of development of distinct populations started already long before farming:

https://unsafeharbour.wordpress.com/2012/01/06/the-origins-of-inequality/

"(...) We all know that the early development in agriculture and civilization began in Eurasia - but it goes back much earlier than that. At a somewhat atemporal level, toolkits of hunter-gatherers have been shown to increase in size and complexity with latitude [larger and more complex toolkits in northern latitudes] (Oswalt, 1976) - the driving cause seeming to be the risk of resource failure (Collard et al., 2005). Developments necessary for cold, risk of resource failure… whatever the cause, Foley (1987) writes: 'although there is a general and global technological development during the Pleistocene, it is in high latitudes that it is most marked; in parts of the tropics the artefacts remained simple.' (...)"

Prior to agriculture, the fastest rates of technological progress were observed in cold climates with short vegetative seasons.

On the other hand, one of important factors which hampered development in the tropics, was surely the parasite load:

https://en.wikipedia.org/wiki/Parasite_load

Tropical climate zones are full of parasites which may infect humans, compared to temperate and polar climate zones.

bicicleur
21-02-16, 20:18
But as far as I know, Neanderthals were really not imbeciles. If technological advancement can be used as some kind of measure of intellect, then they were intellectually on par with AMH (anatomically modern humans) for a long time.

Neanderthal Mousterian culture was not really inferior to AMH cultures existing at the same time (according to James Shreeve, "The Neandertal Enigma"). They were also not superior. Maybe in some fields less advanced, in some more.

Aurignacian culture became more advanced than Neanderthal cultures (which continued to exist as neighbours of Aurignacians).

However, now we know, that Aurignacians were not pure humans, but had some Neanderthal admixture.

I'm not saying that it was absorption of Neanderthal genes which made Aurignacian technology superior.

It could be down to purely cultural exchange (maybe Neanderthals had some inventions, that humans didn't have, and vice versa - and when mixing, they exchanged their knowledge, forming a technologically superior material culture).

note the diveristy among AMHs
AMHs didn't outcompete Neanderthals, only 2 haplogroups of AMHs - CF and DE - outcompeted both Neanderthals and all other AMH lines

I'm not sure Aurigancians lived in the same areas at the same time as Neanderthals, they probably replaced Neanderthals in certain areas of Europe and consequently increased their territtory

Did Aurignacians have more Neanderthal admixture than other AMHs?

Tomenable
21-02-16, 20:35
I'm not sure Aurigancians lived in the same areas at the same time as Neanderthals, they probably replaced Neanderthals

Physical anthropologists once had some doubts whether Aurignacians were AMHs or Neanderthals, due to their mixed features.

Now genetic research seems to confirm that they were indeed a mixed group of partially Neanderthal origin.


Did Aurignacians have more Neanderthal admixture than other AMHs?Oase1 had much more than modern people - do we have any other Aurignacian genomes (was Kostenki14 also one of them?). Already physical anthropologists discovered some Neanderthal traits in AMH skeletons from Peștera cu Oase; aDNA confirms:

https://en.wikipedia.org/wiki/Peștera_cu_Oase

LeBrok
21-02-16, 23:04
"Human social structures change so slowly and with such difficulty as to suggest an evolutionary influence at work. Modern humans lived for 185,000 years as hunters and gatherers before settling down in fixed communities. Putting a roof over one’s head and being able to own more than one could carry might seem an obvious move. The fact that it took so long suggests that a genetic change in human social behavior was required and took many generations to evolve." It is a neat argument, I like it.


The traits favored by selection in an agrarian world also proved beneficial in trade and industrialization.

"Turning up punctually for work every day and enduring eight eight hours or more of repetitive labor is far from being a natural human behavior. Hunter-gatherers do not willingly embrace such occupations, but agrarian societies from their beginning demanded the discipline to labor in the fields and to plant and harvest at the correct times. Disciplined behaviors were probably evolving gradually within the agrarian English population for many centuries before 1200, the point at which they can be documented."
Unlike the long evolutionary process to becoming hunter gatherer and Homo Sapience, this change to farming way of life came mostly through selection and emphasis of already existing traits. Just making more copies of them, fine tuning of existing genes (new alleles), and them becoming more and more frequent through population. Few thousand years is way too short time to develope a perfect agricultural genome. If it was the case, we wouldn't have problems of wear and tear on our joints and spine from hard repetitive work, our kids would stop playing warriors running around with guns, but instead would love to imitate plowing fields or milking cow, to get the training and head start in vital skills. Likewise everybody would be lactose tolerant by now and could eat gluten.
I think from all the people where agriculture started first, Chinese (and few others in the area) are the most equipped to do repetitive work. Perhaps agricutlure started way earlier over there, or they mixed less with local hunter gatherers. Sometimes I have a feeling that they are the only ones who can enjoy the long repetitive work. It doesn't need to be hard physical work, but just sitting or standing and manually doing something for long hours, with pleasant and satisfying feeling. If you feel good doing something why would you stop? That's how the natural instinct works, and it has to be genetic.
This is East Asian trick in being very productive and highly educated, both taking countless hours of repetitive tasks. Things that come easy to them. Ones they embrace the right economic system of production they are very quickly catching to the West, with few already there like Japan, Singapore, Hong Kong, Taiwan and South Korea.
Other signs of this joyful workaholism are: Japanese companies have to force people to go home after working hours, otherwise they keep working for free! Korean government introduced legislation to limit the school hours for Korean kids. No study after 10pm! Of course it is well seen, as a sign of caring for kids, to break this law. Things unheard of in other parts of the world.

Tomenable
26-02-16, 10:29
When it comes to autism (discussed here before) - it is apparently 5 times more common among men, than among women:

https://www.youtube.com/watch?v=nQcgD5DpVlQ


https://www.youtube.com/watch?v=nQcgD5DpVlQ