Water is still put in the milk, aside from i being economical it's also because drinking milk from cow directly could give you diarrhea and taste is too much form many people. I've seen the process on bio farm with manual milking.
Interesting. Does it work for all "races" . Because I thought Caucasian developed high rate of lactose tolerance genetically to compensate for lack of vitamin D from sun light among other things but e.g. Asians have higher rate of lactose intolerance.
As far as I am aware, yes. Maybe not with a 100% success rate, but yes. I am white as snow and when I went vegan I developed a lactose intolerance (every once in a blue moon I'll accidentally grab some milk chocolate or something without realising.) While there's probably some genetics at play, western cultures have a much higher focus on milk, so you are much more likely to just drink/consume milk with some regularity throughout your life, from childhood, so you just never lose those... well, I don't know, enzymes, I think? Every mammal starts out with a lactose tolerance, after all.
interesting. I've always read about genes version never about time between consumption of lactose.
As for mammals, it's unique for humans to be able to drink other species milk on large scale AFAIK. Even adult cats can get into trouble after drinking cow milk.