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July 7 Information
i'm from india and as you all may very well know, alcohol in india is pretty much shunned. a very small percentage of people regularly consume it, me among them. now, i've always known that the reason why Western people drink so much alcohol and we Indians, and Asians for that matter, don't is because of simple cultural differences. But one of my friends said that it's something to do with colder temperatures in Western countries and the body able to "handle" alcohol better at lower temperatures.
can somebody please shed some light on this?
thanks -- 117.197.234.248 ( talk · contribs) 05:09, 7 July 2013 (UTC)
- It has nothing to do with cultural difference. In India people cannot buy branded wines hence they drink the unhealthy Rice wine. Now people in US or Europe has more money hence they drink Grape wine. It is all clear cut case of money, not cultural difference. The Legend of Zorro 06:10, 7 July 2013 (UTC)
- It also has nothing to do with colder temperatures.
Darwin in Australia's Northern Territory has the world's highest alcohol consumption rates. It is a very hot and humid place.
HiLo48 (
talk) 06:58, 7 July 2013 (UTC)
- Can we get a ref for " Darwin in Australia's Northern Territory has the world's highest alcohol consumption rates"? 202.155.85.18 ( talk) 01:09, 9 July 2013 (UTC)
- While there isn't the possible health benefits of red wine, I'm not aware there's anything particularly unhealthy about rice wine compared to grape wine or alcoholic beverages in general (in other words, not counting the health issues alcohol consumption may bring). I'm not of course counting the health risks of drinking wine contaminated with methanol and other crap that comes from adulteration which isn't tied to the type of beverage per se. (Quality control and production can make a difference as well and these do depend on the type of alcoholic beverage but I don't think rice wine necessarily comes out bad here.) Also I think you overstate, the significance of grape wine in Western countries, in a number of them, beer is far more common than wine, in others vodka or other beverages are common. In addition, while still expensive for the average Indian, I expect cheap house brands etc are a big proportion of the market in some places and I suspect some discerning drinkers would prefer a quality rice wine to that sort of stuff. Nil Einne ( talk) 19:52, 8 July 2013 (UTC)
- It also has nothing to do with colder temperatures.
Darwin in Australia's Northern Territory has the world's highest alcohol consumption rates. It is a very hot and humid place.
HiLo48 (
talk) 06:58, 7 July 2013 (UTC)
Interested editors may see Sura (alcoholic beverage). The Legend of Zorro 07:09, 7 July 2013 (UTC)
- Western doesn't equal cold. Check the Mediterranean countries: in the North the drink wine, in the South they smoke pot. Or the US, many parts are hot, but alcohol is also consumed there. It's all about culture and being able to get it. OsmanRF34 ( talk) 07:35, 7 July 2013 (UTC)
| off-topic religious discussion; this is the Science ref desk |
|---|
| The following discussion has been closed. Please do not modify it. |
|
- Another factor that might lead to higher alcohol consumption is a lack of safe alternative drinks, such as areas with unsafe water. Of course, most of the Western world has safe drinking water (with exceptions, like Mexico), does all of India ? StuRat ( talk) 07:44, 7 July 2013 (UTC)
- The alcohol flush reaction may be a factor, though from the article it sounds like India is on the periphery of the affected region. Wnt ( talk) 07:58, 7 July 2013 (UTC)
Looking at the List of countries by alcohol consumption, there certainly does seem to be a bias towards colder countries consuming more alcohol. There's only two countries in the top 20 with what I would consider warm climates (Portugal and Andorra). There's also a strong bias towards high alcohol consuming countries being in Europe, so a cultural factor may also be at play (South Korea is the only non-European country in the top 20). 202.155.85.18 ( talk) 01:17, 9 July 2013 (UTC)
- I would propose an alternate hypothesis; that fermented beverages are more popular in cultures from colder climates, because in warm climates it is more difficult to control the process of alcoholic fermentation [1]. Modern technology makes this a surmountable obstacle, but it was during more primitive periods that these cultural aversions to alcohol developed. The differential in exposure to ethanol has lead to genetic differences expressed in the efficacy of alcohol dehydrogenase across different populations [2]. 202.155.85.18 ( talk) 02:03, 9 July 2013 (UTC)
- Might it have something to do with body size? I don't have the stats, but it seems from pictures and videos of crowds that Indians (and most South Asians) are generally on the small side, compared to "Northerners". Might be related to the climate (bigger people stay warmer). If this is true, and not a misjudgment of mine, it makes sense that alcohol may have gotten a bad reputation among those who can't hold it as well. Nobody likes puking and passing out by ten. InedibleHulk (talk) 02:35, 9 July 2013 (UTC)
Besides the Lawrence Krauss' book (A Universe From Nothing), what other works enter into the question above? What part of Physics deal with it? Do we know something about it? OsmanRF34 ( talk) 15:31, 7 July 2013 (UTC)
- The big bang happened because there was nothing to prevent it. μηδείς ( talk) 17:08, 7 July 2013 (UTC)
- Never thought it about that way. Thanks! InedibleHulk (talk) 02:43, 9 July 2013 (UTC)
- "Obvious" is obviously a relative thing. Why doesn't a mini-micro-universe just get created in my living room every second day of the week? There's certainly nothing to prevent it. -- Jack of Oz [Talk] 02:07, 10 July 2013 (UTC)
- Check out cosmogony. People hypothesize about it (e.g. the article mentions maybe a collision of 11-dimensional membranes caused our universe, maybe just one in a multiverse). But nobody really knows what caused the big bang, or what happened before it. We don't know if it possible ever to know. If (if!) time itself started to exist at the bang, does it even make sense to say "before" and "caused". It's really quite wide open. 88.112.41.6 ( talk) 17:24, 7 July 2013 (UTC)
- Actually we dont even know if this "big bang"-theory is right. Its just an educated guess. --
Kharon (
talk) 20:40, 7 July 2013 (UTC)
- Big bang cosmology—which describes a universe expanding and cooling from a very hot, dense, uniform initial state—is true beyond resonable doubt at this point. But it doesn't have anything to say about this question, unless you call that initial state "nothing". -- BenRG 22:07, 7 July 2013 (UTC)
- On a similar level you don't even know if anything except you exists. The big bang is as good as we can come up with, but then again, your own belief that anything outside your own mind exists is no less of an educated guess. -- Jayron 32 02:51, 8 July 2013 (UTC)
- We know nothing about it. I may as well point out that (according to negative reviews I've seen) the "nothing" in Krauss's book title is the quantum vacuum, which has a lot of structure and really doesn't deserve to be called "nothing". The question of how the universe got from a vacuum to the precursor of its present-day state is easier and less interesting that the question of where the vacuum came from. Even so, no one knows the answer, and no one even knows if the alleged initial vacuum existed. -- BenRG 22:07, 7 July 2013 (UTC)
The idea that there exists such a thing as "physical existence" may be wrong, at least there is no evidence for it. If the only form of existence is mathematical i.e. we exist in the same sense that the function f(x) = sqrt(1+x^2) exists, then there is no problem to solve here. Most philosphical problems that have been resolved were resolved in this way. E.g. there exists no such thing as a "soul", God doesn't exist, living organisms are not fundamentally different from "dead" matter, etc. etc. etc. So, if there is an intractible problem, you have to seriously consider if it could be an artifact of some unproven assumption we are making. Count Iblis ( talk) 14:30, 8 July 2013 (UTC)
- Those are the same learned scientists who argued that bumblebees can't fly. ←
Baseball Bugs
What's up, Doc?
carrots→ 02:51, 9 July 2013 (UTC)
- That's a really annoying thing to say Bugs...where is your reference for these scientists who said that. Only a total idiot would say that bumblebees can't fly - they might say "We don't understand how bumblebees can fly"...but seriously...who would ever say that they can't! The truth is that no scientist who was researching this ever made that statement. The true story is explained in
Bee#Flight - and I strongly suggest you read it. So [CITATION NEEDED] or stop spouting this drivel.
SteveBaker (
talk) 17:17, 9 July 2013 (UTC)
- I strongly suggest you refrain from further personal attacks in front of the OP. ←
Baseball Bugs
What's up, Doc?
carrots→ 22:54, 9 July 2013 (UTC)
- Calling your comment "drivel" is not a personal attack - it is a statement of fact. Please either provide a reference for what you said or retract it. StewieCartman ( talk) 10:59, 10 July 2013 (UTC)
- I strongly suggest you refrain from further personal attacks in front of the OP. ←
Baseball Bugs
What's up, Doc?
carrots→ 22:54, 9 July 2013 (UTC)
- That's a really annoying thing to say Bugs...where is your reference for these scientists who said that. Only a total idiot would say that bumblebees can't fly - they might say "We don't understand how bumblebees can fly"...but seriously...who would ever say that they can't! The truth is that no scientist who was researching this ever made that statement. The true story is explained in
Bee#Flight - and I strongly suggest you read it. So [CITATION NEEDED] or stop spouting this drivel.
SteveBaker (
talk) 17:17, 9 July 2013 (UTC)
- Those are the same learned scientists who argued that bumblebees can't fly. ←
Baseball Bugs
What's up, Doc?
carrots→ 02:51, 9 July 2013 (UTC)
- Actually, all that exists is the physical: mathematics is a human invention to model the physical world. Without humans, the physical would still be here, but there would be no mathematics to describe it. -- Jayron 32 02:08, 9 July 2013 (UTC)
Within a species, I've seen different terms for the distinguishable varieties used for Human (Race), wild animals (Subspecies) and domesticated animals (Breed). What I'm wondering is whether the differences between different populations of Humanity (Say between the Xhosa in Southern Africa and the Ainu in Northern Japan) are larger, smaller or about the same as the differences between the two subspecies of Eastern Gorilla (to pick a relatively close relative of man with recognized subspecies)? From the wikipedia article, Neanderthals where either a different subspecies as modern man within the same species or a different species within the same genus as modern man, so I guess the rules on what is or is not a common subspecies aren't completely fixed. So I don't know if this has an answer... Naraht ( talk) 17:00, 7 July 2013 (UTC)
- This is pretty similar to [3]. I posted a link there to a paper which pointed out that yes, humans varied as much as some of the ape "subspecies" - however, its conclusion was that the primate subspecies were unjustified.
- The situation is muddled from the top down, though - we actually have the high weirdness of Homo sapiens neanderthalensis, which was renamed to a full-fledged species Homo neanderthalensis based on the conclusion that Neanderthals didn't breed with modern humans. Immediately afterward people decided they did... but kept the name. So technically the Ainu (like any Eurasian) would be Homo sapiens x Homo neanderthalensis, and the Xhosa would be plain Homo sapiens, at least until someone more industrious figures out where they live and what early human species they bred with. Etcetera.
- "There is something fascinating about science. One gets such wholesale returns of conjecture out of such a trifling investment of fact." -- Mark Twain
- To follow up a bit further though, I should point out that Neanderthals themselves were not so different from modern humans, building quite large structures, [4] collecting medicinal herbs for the ill ( Shanidar Cave) etc. (I know there are some naysayers about the second, and the evidence was destroyed in the bombing of Iraq, but I find the original explanation most believable). We're not that different from them in appearance or behavior, most of us are the results of hybridization with them ... I think that the conservative thing is to say that they and Denisovans are the subspecies level, which puts all modern humans at something less than that. I think there is room for thought here; we might see grounds to justify a more closely related subspecies in some modern, isolated, physically distinct human population as I commented in the previous discussion. But I don't want to miss the obvious point that humans probably had subspecies and lost them all to our invasive habit long ago. Wnt ( talk) 17:53, 7 July 2013 (UTC)
- You've phrased the question well, but I'd encourage you to think more deeply about what what you mean by "differences between different populations." Certainly some human populations have notable phenotypic differences, e.g. eye color, skin color, hair color and structure, etc. But, adding up and quantifying these differences is no easy matter, both technically, and ontologically. And even then, these differences may not mean much in terms of separating out species or subspecies. Are you familiar with the species problem? What about phylogenetics, systematics, and cladistics? I am not an expert in these fields; in fact I find the whole matter rather confusing. So I cannot answer the question, but I believe any good, rigorous investigation should start with understanding these foundational topics and methods. SemanticMantis ( talk) 20:05, 7 July 2013 (UTC)
I'm reading this this paper as an amateur and there is something that confuses me. On page 80 it says:
- Because the effective population size of the X chromosome is three times that of mtDNA and the Y chromosome and threequarters that of autosomes, this age agrees well with the estimates of the age of the MRCAs for mtDNA and Y chromosomal sequences, which fall 100,000−200,000 years ago1,2,27, and for β-globin gene sequences, which are 750,000±210,000 years.
I can understand that for a population composed of an equal number of males and females there is going to be 3 times as many X chromosomes as Y chromosomes, but I don't understand why is says 3 times that of mtDNA. For every male and female pair there are 3Xs and 1Y but there are two sets of mtDNA. I'm not sure what I'm missing. 87.194.131.188 ( talk) 20:34, 7 July 2013 (UTC)
- Actually I think I've worked it out. If a couple are described as m.x.y for the male and M.X1.X2 for the female the pattern of inheritance for their children is going to be M.X1.y, M.X2.y, M.X1.x, M.X2.x. giving three times as much variation for the X chromosome as both Y and mtDNA.
87.194.131.188 ( talk) 20:55, 7 July 2013 (UTC)
- I suppose this may be very slightly inaccurate due to mtDNA mosaicism (see human mitochondrial genetics) and possible paternal mtDNA transmission. As the first article there mentions, it is possible for twins to end up receiving different levels of a disease mtDNA. The stuff can even recombine, at least in some somatic cells! [5] However, there's no real way for multiple mtNDA lineages to persist within the female bloodline for very long, so I assume the impact of all this is still pretty small. Wnt ( talk) 21:35, 7 July 2013 (UTC)
- A simpler but completely equivalent interpretation is that effective population size refers to the number of genes that pass on to the next generation. Males have mitochondrial DNA, but that's irrelevant because they won't pass it to their offspring. In terms of gene flow, it's as if they had no mtDNA at all. -- Bowlhover ( talk) 02:03, 8 July 2013 (UTC)
| Science desk | ||
|---|---|---|
| < July 6 | << Jun | July | Aug >> | July 8 > |
| Welcome to the Wikipedia Science Reference Desk Archives |
|---|
| The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages. |
July 7 Information
i'm from india and as you all may very well know, alcohol in india is pretty much shunned. a very small percentage of people regularly consume it, me among them. now, i've always known that the reason why Western people drink so much alcohol and we Indians, and Asians for that matter, don't is because of simple cultural differences. But one of my friends said that it's something to do with colder temperatures in Western countries and the body able to "handle" alcohol better at lower temperatures.
can somebody please shed some light on this?
thanks -- 117.197.234.248 ( talk · contribs) 05:09, 7 July 2013 (UTC)
- It has nothing to do with cultural difference. In India people cannot buy branded wines hence they drink the unhealthy Rice wine. Now people in US or Europe has more money hence they drink Grape wine. It is all clear cut case of money, not cultural difference. The Legend of Zorro 06:10, 7 July 2013 (UTC)
- It also has nothing to do with colder temperatures.
Darwin in Australia's Northern Territory has the world's highest alcohol consumption rates. It is a very hot and humid place.
HiLo48 (
talk) 06:58, 7 July 2013 (UTC)
- Can we get a ref for " Darwin in Australia's Northern Territory has the world's highest alcohol consumption rates"? 202.155.85.18 ( talk) 01:09, 9 July 2013 (UTC)
- While there isn't the possible health benefits of red wine, I'm not aware there's anything particularly unhealthy about rice wine compared to grape wine or alcoholic beverages in general (in other words, not counting the health issues alcohol consumption may bring). I'm not of course counting the health risks of drinking wine contaminated with methanol and other crap that comes from adulteration which isn't tied to the type of beverage per se. (Quality control and production can make a difference as well and these do depend on the type of alcoholic beverage but I don't think rice wine necessarily comes out bad here.) Also I think you overstate, the significance of grape wine in Western countries, in a number of them, beer is far more common than wine, in others vodka or other beverages are common. In addition, while still expensive for the average Indian, I expect cheap house brands etc are a big proportion of the market in some places and I suspect some discerning drinkers would prefer a quality rice wine to that sort of stuff. Nil Einne ( talk) 19:52, 8 July 2013 (UTC)
- It also has nothing to do with colder temperatures.
Darwin in Australia's Northern Territory has the world's highest alcohol consumption rates. It is a very hot and humid place.
HiLo48 (
talk) 06:58, 7 July 2013 (UTC)
Interested editors may see Sura (alcoholic beverage). The Legend of Zorro 07:09, 7 July 2013 (UTC)
- Western doesn't equal cold. Check the Mediterranean countries: in the North the drink wine, in the South they smoke pot. Or the US, many parts are hot, but alcohol is also consumed there. It's all about culture and being able to get it. OsmanRF34 ( talk) 07:35, 7 July 2013 (UTC)
| off-topic religious discussion; this is the Science ref desk |
|---|
| The following discussion has been closed. Please do not modify it. |
|
- Another factor that might lead to higher alcohol consumption is a lack of safe alternative drinks, such as areas with unsafe water. Of course, most of the Western world has safe drinking water (with exceptions, like Mexico), does all of India ? StuRat ( talk) 07:44, 7 July 2013 (UTC)
- The alcohol flush reaction may be a factor, though from the article it sounds like India is on the periphery of the affected region. Wnt ( talk) 07:58, 7 July 2013 (UTC)
Looking at the List of countries by alcohol consumption, there certainly does seem to be a bias towards colder countries consuming more alcohol. There's only two countries in the top 20 with what I would consider warm climates (Portugal and Andorra). There's also a strong bias towards high alcohol consuming countries being in Europe, so a cultural factor may also be at play (South Korea is the only non-European country in the top 20). 202.155.85.18 ( talk) 01:17, 9 July 2013 (UTC)
- I would propose an alternate hypothesis; that fermented beverages are more popular in cultures from colder climates, because in warm climates it is more difficult to control the process of alcoholic fermentation [1]. Modern technology makes this a surmountable obstacle, but it was during more primitive periods that these cultural aversions to alcohol developed. The differential in exposure to ethanol has lead to genetic differences expressed in the efficacy of alcohol dehydrogenase across different populations [2]. 202.155.85.18 ( talk) 02:03, 9 July 2013 (UTC)
- Might it have something to do with body size? I don't have the stats, but it seems from pictures and videos of crowds that Indians (and most South Asians) are generally on the small side, compared to "Northerners". Might be related to the climate (bigger people stay warmer). If this is true, and not a misjudgment of mine, it makes sense that alcohol may have gotten a bad reputation among those who can't hold it as well. Nobody likes puking and passing out by ten. InedibleHulk (talk) 02:35, 9 July 2013 (UTC)
Besides the Lawrence Krauss' book (A Universe From Nothing), what other works enter into the question above? What part of Physics deal with it? Do we know something about it? OsmanRF34 ( talk) 15:31, 7 July 2013 (UTC)
- The big bang happened because there was nothing to prevent it. μηδείς ( talk) 17:08, 7 July 2013 (UTC)
- Never thought it about that way. Thanks! InedibleHulk (talk) 02:43, 9 July 2013 (UTC)
- "Obvious" is obviously a relative thing. Why doesn't a mini-micro-universe just get created in my living room every second day of the week? There's certainly nothing to prevent it. -- Jack of Oz [Talk] 02:07, 10 July 2013 (UTC)
- Check out cosmogony. People hypothesize about it (e.g. the article mentions maybe a collision of 11-dimensional membranes caused our universe, maybe just one in a multiverse). But nobody really knows what caused the big bang, or what happened before it. We don't know if it possible ever to know. If (if!) time itself started to exist at the bang, does it even make sense to say "before" and "caused". It's really quite wide open. 88.112.41.6 ( talk) 17:24, 7 July 2013 (UTC)
- Actually we dont even know if this "big bang"-theory is right. Its just an educated guess. --
Kharon (
talk) 20:40, 7 July 2013 (UTC)
- Big bang cosmology—which describes a universe expanding and cooling from a very hot, dense, uniform initial state—is true beyond resonable doubt at this point. But it doesn't have anything to say about this question, unless you call that initial state "nothing". -- BenRG 22:07, 7 July 2013 (UTC)
- On a similar level you don't even know if anything except you exists. The big bang is as good as we can come up with, but then again, your own belief that anything outside your own mind exists is no less of an educated guess. -- Jayron 32 02:51, 8 July 2013 (UTC)
- We know nothing about it. I may as well point out that (according to negative reviews I've seen) the "nothing" in Krauss's book title is the quantum vacuum, which has a lot of structure and really doesn't deserve to be called "nothing". The question of how the universe got from a vacuum to the precursor of its present-day state is easier and less interesting that the question of where the vacuum came from. Even so, no one knows the answer, and no one even knows if the alleged initial vacuum existed. -- BenRG 22:07, 7 July 2013 (UTC)
The idea that there exists such a thing as "physical existence" may be wrong, at least there is no evidence for it. If the only form of existence is mathematical i.e. we exist in the same sense that the function f(x) = sqrt(1+x^2) exists, then there is no problem to solve here. Most philosphical problems that have been resolved were resolved in this way. E.g. there exists no such thing as a "soul", God doesn't exist, living organisms are not fundamentally different from "dead" matter, etc. etc. etc. So, if there is an intractible problem, you have to seriously consider if it could be an artifact of some unproven assumption we are making. Count Iblis ( talk) 14:30, 8 July 2013 (UTC)
- Those are the same learned scientists who argued that bumblebees can't fly. ←
Baseball Bugs
What's up, Doc?
carrots→ 02:51, 9 July 2013 (UTC)
- That's a really annoying thing to say Bugs...where is your reference for these scientists who said that. Only a total idiot would say that bumblebees can't fly - they might say "We don't understand how bumblebees can fly"...but seriously...who would ever say that they can't! The truth is that no scientist who was researching this ever made that statement. The true story is explained in
Bee#Flight - and I strongly suggest you read it. So [CITATION NEEDED] or stop spouting this drivel.
SteveBaker (
talk) 17:17, 9 July 2013 (UTC)
- I strongly suggest you refrain from further personal attacks in front of the OP. ←
Baseball Bugs
What's up, Doc?
carrots→ 22:54, 9 July 2013 (UTC)
- Calling your comment "drivel" is not a personal attack - it is a statement of fact. Please either provide a reference for what you said or retract it. StewieCartman ( talk) 10:59, 10 July 2013 (UTC)
- I strongly suggest you refrain from further personal attacks in front of the OP. ←
Baseball Bugs
What's up, Doc?
carrots→ 22:54, 9 July 2013 (UTC)
- That's a really annoying thing to say Bugs...where is your reference for these scientists who said that. Only a total idiot would say that bumblebees can't fly - they might say "We don't understand how bumblebees can fly"...but seriously...who would ever say that they can't! The truth is that no scientist who was researching this ever made that statement. The true story is explained in
Bee#Flight - and I strongly suggest you read it. So [CITATION NEEDED] or stop spouting this drivel.
SteveBaker (
talk) 17:17, 9 July 2013 (UTC)
- Those are the same learned scientists who argued that bumblebees can't fly. ←
Baseball Bugs
What's up, Doc?
carrots→ 02:51, 9 July 2013 (UTC)
- Actually, all that exists is the physical: mathematics is a human invention to model the physical world. Without humans, the physical would still be here, but there would be no mathematics to describe it. -- Jayron 32 02:08, 9 July 2013 (UTC)
Within a species, I've seen different terms for the distinguishable varieties used for Human (Race), wild animals (Subspecies) and domesticated animals (Breed). What I'm wondering is whether the differences between different populations of Humanity (Say between the Xhosa in Southern Africa and the Ainu in Northern Japan) are larger, smaller or about the same as the differences between the two subspecies of Eastern Gorilla (to pick a relatively close relative of man with recognized subspecies)? From the wikipedia article, Neanderthals where either a different subspecies as modern man within the same species or a different species within the same genus as modern man, so I guess the rules on what is or is not a common subspecies aren't completely fixed. So I don't know if this has an answer... Naraht ( talk) 17:00, 7 July 2013 (UTC)
- This is pretty similar to [3]. I posted a link there to a paper which pointed out that yes, humans varied as much as some of the ape "subspecies" - however, its conclusion was that the primate subspecies were unjustified.
- The situation is muddled from the top down, though - we actually have the high weirdness of Homo sapiens neanderthalensis, which was renamed to a full-fledged species Homo neanderthalensis based on the conclusion that Neanderthals didn't breed with modern humans. Immediately afterward people decided they did... but kept the name. So technically the Ainu (like any Eurasian) would be Homo sapiens x Homo neanderthalensis, and the Xhosa would be plain Homo sapiens, at least until someone more industrious figures out where they live and what early human species they bred with. Etcetera.
- "There is something fascinating about science. One gets such wholesale returns of conjecture out of such a trifling investment of fact." -- Mark Twain
- To follow up a bit further though, I should point out that Neanderthals themselves were not so different from modern humans, building quite large structures, [4] collecting medicinal herbs for the ill ( Shanidar Cave) etc. (I know there are some naysayers about the second, and the evidence was destroyed in the bombing of Iraq, but I find the original explanation most believable). We're not that different from them in appearance or behavior, most of us are the results of hybridization with them ... I think that the conservative thing is to say that they and Denisovans are the subspecies level, which puts all modern humans at something less than that. I think there is room for thought here; we might see grounds to justify a more closely related subspecies in some modern, isolated, physically distinct human population as I commented in the previous discussion. But I don't want to miss the obvious point that humans probably had subspecies and lost them all to our invasive habit long ago. Wnt ( talk) 17:53, 7 July 2013 (UTC)
- You've phrased the question well, but I'd encourage you to think more deeply about what what you mean by "differences between different populations." Certainly some human populations have notable phenotypic differences, e.g. eye color, skin color, hair color and structure, etc. But, adding up and quantifying these differences is no easy matter, both technically, and ontologically. And even then, these differences may not mean much in terms of separating out species or subspecies. Are you familiar with the species problem? What about phylogenetics, systematics, and cladistics? I am not an expert in these fields; in fact I find the whole matter rather confusing. So I cannot answer the question, but I believe any good, rigorous investigation should start with understanding these foundational topics and methods. SemanticMantis ( talk) 20:05, 7 July 2013 (UTC)
I'm reading this this paper as an amateur and there is something that confuses me. On page 80 it says:
- Because the effective population size of the X chromosome is three times that of mtDNA and the Y chromosome and threequarters that of autosomes, this age agrees well with the estimates of the age of the MRCAs for mtDNA and Y chromosomal sequences, which fall 100,000−200,000 years ago1,2,27, and for β-globin gene sequences, which are 750,000±210,000 years.
I can understand that for a population composed of an equal number of males and females there is going to be 3 times as many X chromosomes as Y chromosomes, but I don't understand why is says 3 times that of mtDNA. For every male and female pair there are 3Xs and 1Y but there are two sets of mtDNA. I'm not sure what I'm missing. 87.194.131.188 ( talk) 20:34, 7 July 2013 (UTC)
- Actually I think I've worked it out. If a couple are described as m.x.y for the male and M.X1.X2 for the female the pattern of inheritance for their children is going to be M.X1.y, M.X2.y, M.X1.x, M.X2.x. giving three times as much variation for the X chromosome as both Y and mtDNA.
87.194.131.188 ( talk) 20:55, 7 July 2013 (UTC)
- I suppose this may be very slightly inaccurate due to mtDNA mosaicism (see human mitochondrial genetics) and possible paternal mtDNA transmission. As the first article there mentions, it is possible for twins to end up receiving different levels of a disease mtDNA. The stuff can even recombine, at least in some somatic cells! [5] However, there's no real way for multiple mtNDA lineages to persist within the female bloodline for very long, so I assume the impact of all this is still pretty small. Wnt ( talk) 21:35, 7 July 2013 (UTC)
- A simpler but completely equivalent interpretation is that effective population size refers to the number of genes that pass on to the next generation. Males have mitochondrial DNA, but that's irrelevant because they won't pass it to their offspring. In terms of gene flow, it's as if they had no mtDNA at all. -- Bowlhover ( talk) 02:03, 8 July 2013 (UTC)