Humans were drinking milk before they could digest it(sciencemag.org)
sciencemag.org
Humans were drinking milk before they could digest it
https://www.sciencemag.org/news/2021/01/humans-were-drinking-milk-they-could-digest-it
68 comments
A safer form of water even if you can't make use of the nutrition?
if you have domesticated herds and you live in an arid climate, you can regard your milk animals as portable water fountains that eat vegetable matter which you cannot, and produce protein and hydration more or less on demand, for free.
Hell of a lot easier than oasis hunting.
Hell of a lot easier than oasis hunting.
> for free
Sort of. You have to feed them, often by moving from site to site throughout the year as pastures become overgrazed. Even more importantly, you have to guard them against rustlers. The incentive for someone else to steal your animals is so high that preventing raids ends up dominating your life.
Sort of. You have to feed them, often by moving from site to site throughout the year as pastures become overgrazed. Even more importantly, you have to guard them against rustlers. The incentive for someone else to steal your animals is so high that preventing raids ends up dominating your life.
And thus, the concept of war was born.
I'd bet humans invented warfare way before animal husbandry.
Human's didn't invent war. Insects go to war.
Insects also practice animal husbandry.
That's true, but we can still say humans invented animal husbandry; humans descend from species that didn't practice it.
In contrast, humans have a continuous tradition of war that goes back long before the differentiation of the species.
In contrast, humans have a continuous tradition of war that goes back long before the differentiation of the species.
Hey! Those are OUR mastadons!
From a theoretical perspective, this cannot be a surprise. There is no evolutionary advantage to producing lactase if you don't drink milk. There is a cost, which is why most populations stop producing lactase after weaning.
It isn't possible for lactase persistence to spread in an environment that doesn't already feature adult consumption of milk; this finding was guaranteed before a study began.
It isn't possible for lactase persistence to spread in an environment that doesn't already feature adult consumption of milk; this finding was guaranteed before a study began.
I have little knowledge of evolution theory, can you please help me understand this?
How can one force evolution by invoking a fitness cost? Wouldn't that actually just drive extinction?
I would have thought that if producing lactase when consuming milk has a cost, then over time, milk-consuming populations would suffer and disappear from lower fitness, and the ones who aren't drinking milk would survive and win the genetic race.
How can one force evolution by invoking a fitness cost? Wouldn't that actually just drive extinction?
I would have thought that if producing lactase when consuming milk has a cost, then over time, milk-consuming populations would suffer and disappear from lower fitness, and the ones who aren't drinking milk would survive and win the genetic race.
The fitness "cost" isn't the "net cost." Pretty much everything our bodies do has a cost. Our organs are all consuming a tremendous amount of energy. Our guts harbor bacteria that can absolutely overwhelm the body if they get out. It takes us more than a decade of growth to reach sexual maturity.
You can only determine the value by taking into account the benefit.
Populations that could consume milk, an easy and plentiful supply of calories and calcium, did better off than some of their local neighbors who didn't.
You can only determine the value by taking into account the benefit.
Populations that could consume milk, an easy and plentiful supply of calories and calcium, did better off than some of their local neighbors who didn't.
> I would have thought that if producing lactase when consuming milk has a cost, then over time, milk-consuming populations would suffer and disappear from lower fitness, and the ones who aren't drinking milk would survive and win the genetic race.
Your focus is oddly misplaced. There is a cost of producing lactase, regardless of whether you do anything with it. This cost indeed caused those who continued to produce lactase after weaning to suffer and disappear from lower fitness. That is why, from a world perspective, almost nobody today can digest lactose in adulthood.
If you drink milk as an adult, you still have to pay the normal cost of producing lactase. But you get the benefit of being able to metabolize the lactose you're already consuming. This makes the production of lactase profitable.
Note that this relies on you drinking milk. If adults are not drinking milk, the ordinary dynamic of lactase production being a waste of energy that lowers your fitness will prevail.
Your focus is oddly misplaced. There is a cost of producing lactase, regardless of whether you do anything with it. This cost indeed caused those who continued to produce lactase after weaning to suffer and disappear from lower fitness. That is why, from a world perspective, almost nobody today can digest lactose in adulthood.
If you drink milk as an adult, you still have to pay the normal cost of producing lactase. But you get the benefit of being able to metabolize the lactose you're already consuming. This makes the production of lactase profitable.
Note that this relies on you drinking milk. If adults are not drinking milk, the ordinary dynamic of lactase production being a waste of energy that lowers your fitness will prevail.
The fitness of the group drinking the milk was higher than group not drinking the milk (even with an intolerance). After drinking started, the individuals with a tolerance had higher fitness than the group without. This is super simplified.
You are forgetting that drinking milk was beneficial(lots of extra calories for example), this obviously outweighed the downside of lactose intolerance.
Yes. And it didn't have to be an all-or-nothing thing. It's also plausible that cow milk was used for babies who lost their mother. So to create an evolutionarily significant effect, it was sufficient to simply select for babies who could keep drinking cow's milk for longer and longer, on average.
You might be interested to know that there are -- broadly -- three lactase production strategies that humans exhibit.
Everyone produces lactase as an infant, for obvious reasons.
Some people cease producing lactase at some point in childhood, so that they are unable to digest lactose as adults.
Some people continue producing lactase throughout their lives, so that they are always able to digest lactose.
But some people continue producing lactase as long as they maintain regular dietary lactose intake, even if that circumstance lasts well into adulthood. However, if they ever go for an extended period without consuming lactose, they permanently cease lactase production.
Everyone produces lactase as an infant, for obvious reasons.
Some people cease producing lactase at some point in childhood, so that they are unable to digest lactose as adults.
Some people continue producing lactase throughout their lives, so that they are always able to digest lactose.
But some people continue producing lactase as long as they maintain regular dietary lactose intake, even if that circumstance lasts well into adulthood. However, if they ever go for an extended period without consuming lactose, they permanently cease lactase production.
Removing the ability to drink milk also comes at a cost. You body has to have the program to remove lactase production exactly when appropriate else you die or get hurt.
> From a theoretical perspective, this cannot be a surprise.
Going off the crappy title "Humans were drinking milk before they could digest it" Don't you find that surprising? Why drink milk if it does nothing for you?
> From a theoretical perspective, this cannot be a surprise.
Going off the crappy title "Humans were drinking milk before they could digest it" Don't you find that surprising? Why drink milk if it does nothing for you?
> Don't you find that surprising? Why drink milk if it does nothing for you?
You can view milk as a mixture of four basic nutrients: water, fat, protein, and sugar. What we're discussing here is the sugar. No one anywhere has problems digesting the protein or fat.
So the answer to your question is, because milk is quite nutritious even ignoring the value of the sugar. Lactose-intolerant populations today frequently consume yoghurt, cheese, and even milk for this reason. Yoghurt and cheese contain negligible lactose. (A fun way to think about this is: take out the sugar from the milk and you get yoghurt. Take out the water from that and you have cheese. Take out the protein from that and you have butter. Of course, that's not really how these things are made; you get butter by separating the fat from milk. But still.)
Metabolizing the lactose in milk gives you more than you were already getting, but you were already getting plenty.
You can view milk as a mixture of four basic nutrients: water, fat, protein, and sugar. What we're discussing here is the sugar. No one anywhere has problems digesting the protein or fat.
So the answer to your question is, because milk is quite nutritious even ignoring the value of the sugar. Lactose-intolerant populations today frequently consume yoghurt, cheese, and even milk for this reason. Yoghurt and cheese contain negligible lactose. (A fun way to think about this is: take out the sugar from the milk and you get yoghurt. Take out the water from that and you have cheese. Take out the protein from that and you have butter. Of course, that's not really how these things are made; you get butter by separating the fat from milk. But still.)
Metabolizing the lactose in milk gives you more than you were already getting, but you were already getting plenty.
>That undercuts a myth, propagated by white supremacists, that lactase persistence and milk drinking are somehow associated with white Europeans.
Isn't it most associated with that ethnic group? https://commons.wikimedia.org/wiki/File:Lactase_persistence_...
Even a broken clock can be right...
Isn't it most associated with that ethnic group? https://commons.wikimedia.org/wiki/File:Lactase_persistence_...
Even a broken clock can be right...
I find that whole statement in the article totally unnecessary, especially from someone calling themselves science mag.
To be honest I found the actual report from the original study to be far more enlightening.
https://www.nature.com/articles/s41467-020-20682-3
From their discussion section
>Our study provides a rare opportunity to link the LP status of specific ancient individuals with direct evidence for their consumption of milk, drawing on combined palaeoproteomic and archaeogenetic investigations. This research clearly demonstrates that ancient African individuals who do not appear to have had a genetic adaptation enabling lactose digestion were nonetheless drinking milk. As noted, not all individuals or populations who drink milk have LP, and ancient dairy consumption may have been enabled by fermentation practices10,11 or gut microflora12, as is suggested for populations today.
That's actually pretty awesome. Yet the news article wipes it away with a snide comment about white supremacy.
Why not explain how Africans seemingly adapted to drinking milk in ways that were different to Europeans? Why not talk about the possibilities this opens into more research and just how adaptable the human body really is?
It turns what's actually a pretty amazing discovery into some political baiting nonsense and I really dislike how that kind of thing is creeping it's way even into scientific reporting.
To be honest I found the actual report from the original study to be far more enlightening.
https://www.nature.com/articles/s41467-020-20682-3
From their discussion section
>Our study provides a rare opportunity to link the LP status of specific ancient individuals with direct evidence for their consumption of milk, drawing on combined palaeoproteomic and archaeogenetic investigations. This research clearly demonstrates that ancient African individuals who do not appear to have had a genetic adaptation enabling lactose digestion were nonetheless drinking milk. As noted, not all individuals or populations who drink milk have LP, and ancient dairy consumption may have been enabled by fermentation practices10,11 or gut microflora12, as is suggested for populations today.
That's actually pretty awesome. Yet the news article wipes it away with a snide comment about white supremacy.
Why not explain how Africans seemingly adapted to drinking milk in ways that were different to Europeans? Why not talk about the possibilities this opens into more research and just how adaptable the human body really is?
It turns what's actually a pretty amazing discovery into some political baiting nonsense and I really dislike how that kind of thing is creeping it's way even into scientific reporting.
I don’t know. The media today is prone to stirring things up just because they can. I think it does a disservice to society to latch on to a boogeything without evidence or when evidence is disputed.
All hacks are Russia or North Korea. Rigor and science (in some examples) perpetuate racism, etc. but it DOES generate clicks, that’s for sure.
All hacks are Russia or North Korea. Rigor and science (in some examples) perpetuate racism, etc. but it DOES generate clicks, that’s for sure.
Because, unfortunately, lactase persistence has been turned into a white supremacist talking point, as proof of a purported fundamental genetic separation between black Africans and white Europeans. It's become necessary to explicitly distance oneself from such ideologies, as people who subscribe to them become more overt in their bigotry and, in so doing, threaten to upset the social stability that makes research like this possible to conduct and disseminate.
IMO the statement doesn't undercut the points expressed in the discussion section. I don't understand the kneejerk oversensitivity to it among people who ostensibly are able to read these types of articles critically and dispassionately.
It's also worth mentioning that certain ethnic groups in East Africa feature hereditary lactase persistence (via a different SNP from European and Asian LP groups).
IMO the statement doesn't undercut the points expressed in the discussion section. I don't understand the kneejerk oversensitivity to it among people who ostensibly are able to read these types of articles critically and dispassionately.
It's also worth mentioning that certain ethnic groups in East Africa feature hereditary lactase persistence (via a different SNP from European and Asian LP groups).
>I don't understand the kneejerk oversensitivity to it among people who ostensibly are able to read these types of articles critically and dispassionately.
Because I expect reporting on scientific reports and journal articles to be critical and dispassionate. I expect it to report the methods, results and discussion from the original paper and summarize it in a succinct easy to understand way, not inject political statements referencing the nonsense rantings of idiots on the internet that have no business being in a report about a discovery in which the authors themselves completely refrain from referencing any such thing.
There's plenty of ways they could have brought those 'theories' into the discussion, had they chosen, without ridiculous emotionally driven, inflammatory language.
For the same reason why posting
'$Topic is just white supremacy'
Is not an acceptable HN comment. It adds literally nothing to the discussion and incites emotionally driven thinking.
Because I expect reporting on scientific reports and journal articles to be critical and dispassionate. I expect it to report the methods, results and discussion from the original paper and summarize it in a succinct easy to understand way, not inject political statements referencing the nonsense rantings of idiots on the internet that have no business being in a report about a discovery in which the authors themselves completely refrain from referencing any such thing.
There's plenty of ways they could have brought those 'theories' into the discussion, had they chosen, without ridiculous emotionally driven, inflammatory language.
For the same reason why posting
'$Topic is just white supremacy'
Is not an acceptable HN comment. It adds literally nothing to the discussion and incites emotionally driven thinking.
That's simply your white fragility speaking. For those with experience speaking on the subject, it is simply another (rather crucial) aspect of the science as it applies to our contemporary society.
The article was sufficiently neutral; your hysteria is the only issue.
Food is politics. Until we're back to scavenging from the nutrient-supporting biome in our immediate vicinity - as long as diet is subject to policy and public sentiment - what is and isn't available to eat and how it interacts with our bodies is inherently both scientific and political, and both deserve mention at points of intersection like this.
The article was sufficiently neutral; your hysteria is the only issue.
Food is politics. Until we're back to scavenging from the nutrient-supporting biome in our immediate vicinity - as long as diet is subject to policy and public sentiment - what is and isn't available to eat and how it interacts with our bodies is inherently both scientific and political, and both deserve mention at points of intersection like this.
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Its going to be really unfortunate for society when white supremacists start talking about how much they like air and water
Pretty certain this was a 4chan operation 'milk is racist' where they would go and drink milk in public. They try and get random things banned. Like rainbows and milk
Really? Did this article really have to go there and bring that up? Does it do anything to enhance the story at all or is it just dredging up mud for no productive reason, whatsoever?
When you've got a culture where all research must be "relevant" don't be surprised when tenuous connections are made in order to sustain the grants.
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It's true that lactose intolerance is quite uncommon in Northern Europe -- to the extent that some even consider it a defect - but most people who'd do that also rarely realise that milk drinking isn't the norm everywhere.
Besides, the ability to drink milk developed independently more than once during human history.
Besides, the ability to drink milk developed independently more than once during human history.
Not really, it’s more common in parts of Saudi Arabia and Africa than Germany or Russia. https://upload.wikimedia.org/wikipedia/commons/f/ff/Lactose_...
It’s one of those things somewhat associated with what is considered race, but not all that closely. Further, the underlying data is very messy.
It’s one of those things somewhat associated with what is considered race, but not all that closely. Further, the underlying data is very messy.
Where is it most common?
Depends on how your counting.
If you mean right now and in terms of total number of people probably India. If you’re talking historic rates it varies depending on time period and how local your talking about. With villages in Asia, Europe, and Africa hitting ~100% at various points.
If you want a national average today then the UK.
If you mean right now and in terms of total number of people probably India. If you’re talking historic rates it varies depending on time period and how local your talking about. With villages in Asia, Europe, and Africa hitting ~100% at various points.
If you want a national average today then the UK.
Yeah I'm curious about what motivated calling out a "myth"... that appears to be not a myth and, why give it more attention?
Seems counterproductive.
Seems counterproductive.
The myth part is that it is common just in Europeans or "caucasian" race. Lactase persistence is relatively common in many parts of the world. Indians have some percentage, Semites and more.
It was unheard of in native Americans and Canadians, and very rare in eastern Asians.
I have no idea about prevalence in Africa, must be nonzero.
It was unheard of in native Americans and Canadians, and very rare in eastern Asians.
I have no idea about prevalence in Africa, must be nonzero.
I saw that map some time ago together with the one here: https://en.wikipedia.org/wiki/Lactase_persistence. However, after having lived in Southeast Asia for a while, I can attest that either the theory is quite wrong, or many many people drink milk with tea and coffee and then have a bad time in the bathroom daily.
The amount of lactose that a person's gut has to process is significantly less if they're only adding it to tea or coffee rather than drinking pints of it every day.
But even so, I gather that people in Southern European countries like Italy don't generally tend to drink milk, apart from added to coffee, and even then only in the mornings.
https://mydearitalia.wordpress.com/2019/03/16/italian-cappuc...
But even so, I gather that people in Southern European countries like Italy don't generally tend to drink milk, apart from added to coffee, and even then only in the mornings.
https://mydearitalia.wordpress.com/2019/03/16/italian-cappuc...
I lived in Spain for most of my life, and plenty of people drink milk in various forms: by itself, with chocolate or other flavourings, with cereals, muesli, etc. Supermarkets have huge shelfs for many brands of milk, and they're sold mainly in 6-packs.
Spain is somewhere in the middle, with 30-35% of people being lactose-intolerant, making it a big market for lactose-free milk apparently.
https://pubmed.ncbi.nlm.nih.gov/9285380/ https://www.bordbia.ie/industry/news/food-alerts/lactose-fre...
https://pubmed.ncbi.nlm.nih.gov/9285380/ https://www.bordbia.ie/industry/news/food-alerts/lactose-fre...
Europeans are not the only group with lactase persistence. It is a trait that is strongly associated with European ancestry.
The problem is graphs like that are used to misleadingly portray lactose tolerance as a “racial” trait, using an out-of-context bit of science to propagate the falsehood of racial differences between Africans and Europeans. The (real) biological difference in skin color ignited a ridiculous false belief that Africans and Europeans constitute different “races,” and scientists have a duty to push back on racist propaganda asserting a “racial difference” where none exists, even on the racists’ own flawed terms.
The high genotypic frequency of lactose persistence in Northern Europe and Saudi Arabia is an interesting and incomplete story about human adaptation to geography and climate (perhaps droughts and harsh winters meant that people were not be able to wait for cheese or yogurt and need to consume large amounts of raw milk?) Another crucial part of the mix is that there is much less genetic diversity in Europe and the Middle East than in Africa.
Regardless, if you read the linked NYT article, it’s clear that a bunch of racist weirdos are stumbling across graphs like the ones you presented and are treating “the ability to drink milk without getting queasy” as another paper bag test. Although it’s ridiculous and abhorrent, such ideas wouldn’t be sustainable if people weren’t convinced pseudoscience was the real thing.
The high genotypic frequency of lactose persistence in Northern Europe and Saudi Arabia is an interesting and incomplete story about human adaptation to geography and climate (perhaps droughts and harsh winters meant that people were not be able to wait for cheese or yogurt and need to consume large amounts of raw milk?) Another crucial part of the mix is that there is much less genetic diversity in Europe and the Middle East than in Africa.
Regardless, if you read the linked NYT article, it’s clear that a bunch of racist weirdos are stumbling across graphs like the ones you presented and are treating “the ability to drink milk without getting queasy” as another paper bag test. Although it’s ridiculous and abhorrent, such ideas wouldn’t be sustainable if people weren’t convinced pseudoscience was the real thing.
It's frustrating that your comment is beginning to slip into transparency, because it's a direct and satisfying answer to the parent's frustration.
Don't shoot the messenger.
Don't shoot the messenger.
Yes. In areas of Africa with higher milk drinking, more have the gene mutations leading to lactase persistence.
Wait, I thought that's what made white people "white".. No?
There's more to milk than lactose, Stone Age people would (and did) kill for the ~4% fat content.
The real trick is to get whale milk... IIRC 42% fat
I read an interview once with a guy who, due to various intolerances and circumstances, ended with a raw meat diet. He has some source of getting good meat, like a farm which also lets him take the animal straight to the butcher, stores it frozen, and eats it just like that, IIRC.
He said that in the beginning, he had trouble digesting it, until he let some meat get to borderline rotting and then ate that. Somehow that colonized his gut with a biome which could digest it, and he was golden after that.
Something to think about in this context...
Personally, I find most milk to be difficult to digest, but cheese and yogurt and such goes over quite well.
Edit: https://archive.is/cX98n https://www.vice.com/en/article/nnqw3q/this-guy-has-eaten-no...
He said that in the beginning, he had trouble digesting it, until he let some meat get to borderline rotting and then ate that. Somehow that colonized his gut with a biome which could digest it, and he was golden after that.
Something to think about in this context...
Personally, I find most milk to be difficult to digest, but cheese and yogurt and such goes over quite well.
Edit: https://archive.is/cX98n https://www.vice.com/en/article/nnqw3q/this-guy-has-eaten-no...
That's a really intresting story, but does the body actually get enough nutrients from just raw meat? No deficiencies in any vitamins or minerals? no risk of scurvy for instance?
The article I linked goes into that. Apparently, fresh meat contains enough vitamin C to keep him going, especially the organs. At the time of the interview, he'd been doing it for several years, and was healthier than ever:
> The organ meat of the animal actually contains vitamin C. And the thing about vitamin C is that you need more of it in a high-carbohydrate diet, but if you're eating carnivorously, there's enough in the animal flesh. So I just eat the organ meat and the connective tissue and everything else.
(Sheep is the animal he is referring to.)
> The organ meat of the animal actually contains vitamin C. And the thing about vitamin C is that you need more of it in a high-carbohydrate diet, but if you're eating carnivorously, there's enough in the animal flesh. So I just eat the organ meat and the connective tissue and everything else.
(Sheep is the animal he is referring to.)
Ah that makes a lot of sense. I assumed he wasn't eating the offal, civilization has made me weak ;)
I think humans in general can eat raw meat. It just doesn't give as much calories compared to cooked meat, plus more chance of diseases which would've been sorted out by the heat if it was cooked.
Beef tartare is quite awesome - raw beef, onion, raw egg yolk.
In Poland it is quite common in restaurants.
https://en.wikipedia.org/wiki/Steak_tartare
In Poland it is quite common in restaurants.
https://en.wikipedia.org/wiki/Steak_tartare
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Wonder if dry aging meat and poultry/game[1] would work for this? It's not cooked.
[1]https://montagne-hautlanguedoc.com/recettes-de-cuisine-tradi...
[1]https://montagne-hautlanguedoc.com/recettes-de-cuisine-tradi...
I'll save anyone a click who was as puzzled as I was.
> All humans can digest milk in infancy. But the ability to do so as an adult developed fairly recently
Is it just me or would "Adult humans were drinking milk..." been a far more clarifying title. I clicked on the link just to make sure I hadn't lost my mind. Humans have been drinking milk since whatever first glimmering of 'human' existed.
> All humans can digest milk in infancy. But the ability to do so as an adult developed fairly recently
Is it just me or would "Adult humans were drinking milk..." been a far more clarifying title. I clicked on the link just to make sure I hadn't lost my mind. Humans have been drinking milk since whatever first glimmering of 'human' existed.
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Maybe they were drinking fermented milk like yoghurt or kefir. No lactate sugars...
The study cannot (and does not attempt to) distinguish whether the milk proteins found within the dental calculus of these thousands-of-years-old remains were as a result of drinking raw milk or consuming fermented milk products. Even the article admits this, but the headline's use of the word 'drink' is misleading and unfortunate.
Fermented milk products are often consumed among populations that cannot digest lactose, because they contain less lactose per weight, or occasionally contain lactase enzyme themselves.
They're a conduit to consuming the calories from milk products without the discomfort and the rapid unhygienic fluid loss that can result from the inability to digest lactose.
Fermented milk products are often consumed among populations that cannot digest lactose, because they contain less lactose per weight, or occasionally contain lactase enzyme themselves.
They're a conduit to consuming the calories from milk products without the discomfort and the rapid unhygienic fluid loss that can result from the inability to digest lactose.
I agree, the article is not supported by the evidence.
They have evidence of dairy consumption, but no evidence of liquid milk consumption.
Is the actual study better? Because if not, then how did this pass peer review?
They have evidence of dairy consumption, but no evidence of liquid milk consumption.
Is the actual study better? Because if not, then how did this pass peer review?
Why is literally everything being spun to cover some racial tension.
You've disproved a myth held by 0.00001 percent of the population. Cool. You gonna disprove flat earthers in your next article about cow flatulence?
Just so damn tired of hearing about racism. We get it, you've got problems.
You've disproved a myth held by 0.00001 percent of the population. Cool. You gonna disprove flat earthers in your next article about cow flatulence?
Just so damn tired of hearing about racism. We get it, you've got problems.
Only 6000 years ago? All the Indians with scriptures linked to cows and milk consumption for millenia before chuckling at this....
The cattle whose milk was easily digestible would have been selectively bred by the humans.
This artificial selection would have been many orders of magnitude more influential than the random, accidental forces alluded to in the article.
Yet, that didn’t happen. So, I’m skeptical about an evolutionary explanation.
Further, the underlying premise of the study is that humans, circa 6000 years ago, were lactose intolerant. Says who? A critical reader would stop there and demand some answers as to why they are making this assumption. (Indeed, even in this thread, you see confusion and disagreements as to which group of living humans are or are not intolerant... yet, I’m supposed to assume that we know with certainty the prevalence of lactose intolerance amongst a population 6000 years ago?!)