Milk isn’t dairy. Because it’s a liability in many parts of the world without abundant fodder or cold climate. Milk can be dangerous without refrigeration in hours.

Dairy is much more than milk. You can consume cheese, yogurt, butter and many other products where the process of making the dairy product eliminates lactose. Think about things like cooking oil — an impossible thing to manufacture efficiently if you lack the resources to grow oil crops and process them. With diary, you just make butter, which is trivial to do.

Domesticated cows and dairy is a pretty miraculous thing. It’s a shame that the excesses and poor practices around industrialized agriculture and economic policy has made it a ethical problem for some people.

Let it ferment. Just add https://en.wikipedia.org/wiki/Kefir

Lard was the "cooking oil" of choice before modern industrial production shifted to seed oils.

And it's still great.

(Though to be sure, lard was the cooking fat of choice in much but not all of the world.)

Lard was also very expensive, typically inaccessible to the layman, who preferred to sell all animal products they could get their hands on.

Fat was inaccessible for cooking on a day to day basis, for anyone but the rich, until the introduction of seed oils.

I prefer purified butter for cooking, milkprotein burns so fast.

> If it's so powerful, why did it not take over the rest of the world.

Time. For going from 1/10 000 000 to 25% of the population in 300 generations (7500 years), you need to have a gene that give you 5% more offsprings at each generation.

And distance. Not so much gene flow across the Mediterranean until we got good at sailing.

And climate. Milk was an advantage against other food sources available at the time in northern Europe, but this wasn't necessarily true elsewhere.

Climate also reflects on the level of available grass that the herders had to take into account when deciding where to move. Europe receives smaller quantities of precipitation as one goes from west to east, and then Europe's lush vegetation transitions into steppes and harsher climate beyond Volga region (Europe-Asia border). It must have been a tough call to decide to go eastward, and from what history tells us, that herders chose to migrate westward, not the other way around.

Europe, throughout most of its history, was a corner of the world. It was a final destination for tribes that were misplaced by overpopulation, decease, and famine from the Middle East and Central Asia.

My theory is that in order for this mutation to spread it must give a cutting edge advantage in an equal environment. However, the migration pressure was toward Europe, not out of it. What's more, other populations already had their ways to utilize derry products and the advantage might not have been so crucial. Therefore, the gene spread had been dependent mostly on internal migration and local populations mixing together.

Of course, this theory has its weaknesses. It does not account for the effects of Alexander the Great, the Silk Road, the Roman empire or the depopulation of Eastern Europe through slave trade during the middle ages. At the same time, most of these factors would open trade routes and cultural exchange but not the large scale migrations necessary for a significant genetic mix. Slavery might offer something, but it was recent and slaves are usually the most disadvantaged group in a society which does not help their genes being promoted.

>You hear stories about people trying everything when they're out of food, maybe trying the cow's milk was a sort of last resort that worked for some lucky people. Then again, you'd think they'd have eaten the cow first.

Maybe it was more desperation from waiting for cheese or something? I'm guessing if they kept milk cattle and didn't eat it they had a reason?

Cheese seems like something that cows would be used for. It's easy to make, it comes from curdled cream, it stores for long periods, and it's calorie dense.

Maybe milk drinking came at a time of extreme hunger where people just drank it directly instead of waiting?

Cheese has about the same lactose as milk, doesn't it?

Hard cheeses contain almost no lactose; it's consumed by bacteria during the maturation process.

A way to store a surplus food that contains high protean and fat is another huge benefit of dairy. Hard cheeses can be stored for years in the right conditions and these conditions are achievable for ancient people (caves).

And if done right, the cheese becomes tastier as it ages.

Not as important today, but more important back then: aging your cheese also concentrates the salt. Salty foods are tasty.

Good point. Back then salt was valuable in places just short distances from the ocean. Humans need salt, especially when doing hard physical labor, sweating all day.

rwh86 is correct. That was part of my reasoning. I was thinking aged fermented cheeses not fresh cheeses, which do have more lactose.

Aged fermented cheese is what I was figuring they would have made, because of the lactose issues. These take several months to years to make. I was lumping in higher lactose things like milk, soft unripened cheeses and yogurts together as 'high lactose desperation foods' as arguably, all were likely consumed for the same reasons early on.

I would guess the lower lactose fermented cheeses would have been favoured earlier though. Humans have a history of fermentation and the utility of aged cheese is kind of hard to beat as far as such things go regarding fat and calorie content and preservability.

Eurasia focused more on mare's milk and China and other rice dominated agricultures had no room for large concentrations of herds.

> China and other rice dominated agricultures had no room for large concentrations of herds.

Yeah it was discussed recently: https://news.ycombinator.com/item?id=24373939

tl;dr: rice was so efficient that there was no point in raising cattle

>If it's so powerful, why did it not take over the rest of the world, or at least the rest of Eurasia? You'd think just a few people having kids with foreign populations would make the gene conquer the whole planet? They had cows in other places as well, right?

It's cooler in Europe. Food stays better longer there. For example the daily mean temperature in Prague in July is 20 C, with a low of 15 C, so you could easily keep a cellar below that. Cheese will keep for a while. Plus, there's often a nearby mountain range with a convenient glacier:

https://en.wikipedia.org/wiki/Ice_trade#Pre-19th_century_met...

Uhh, they just drank different milk. Ox milk, goat milk, etc.

Cattle are not always found in other places.

You might be thinking of a different animal. An ox isn't a good choice as an milking animal, as it typically is a castrated male bovine. If female, it would at least produce milk, but then it would just be a cow used for plowing, and would have the same milk as a dairy cow: https://en.wikipedia.org/wiki/Ox. Maybe you mean a water buffalo?

Lactose is present in all mammal milks to some degree and thus lactase persistence can have some benefits regardless of the specific animal the milk comes from.

Goats milk aminoprofile is closer to human milk. Cows milk is 90/10 casein/wheyprotein, goats milk is 60/40 or 40/60 IIRC.