Now , modern society has a never ending supply of domesticated tame animals to eat and to take milk and eggs from. Primitive humans , being hunter gatherers, were totally dependent on the success of a hunt. If things didn't go well, then they didn't have meat for a while, and lived more on a plant based diet, which many say was their predominant food source in the first place.
So when did this domestication start? It's generally agreed that the first animals to have been domesticated and tamed and used for food were sheep, and then goats, around 9000 years ago. That's a very short time in human history. This is really when humans starting eating a much more substantial amount of meat compared to all the meat eating in earlier times. Pigs , and cattle, started being domesticated around 7000 BC. It's at this time that Dairy production started. In the wild, primitive humans couldn't count on killing lactating females, so might not have used dairy at all. The female animals were killed for the same meat as the males.
Why humans took such a liking to milk is still a bit of a mystery to me. I realize that milk was considered a valid and useful food. But I'm not sure where we developed the taste buds for it in the first place! Much of the world's population is lactose intolerant. Most Asians and Africans do not have dairy in their diet. In fact, I read a few years ago , that more people on the planet did NOT use dairy than did. This might be changing as our SAD Diet (Standard American Diet) seems to be taking roots all around the world.
As you all probably know and realize, no species in evolutionary history has ever used the milk of other animals in their diet. AND , no species ever drank milk beyond childhood. Milk evolved as the perfect food for the baby animals of their specific species, and became unnecessary as the animal began to age. Humans have a very unique position, and a special claim to fame, therefore, in all of mammalian history, for our proclivity to dairy products. Dr. Klaper, well known Vegan medical doctor, once said in a lecture that I attended thatjust because humans started eating something 10,000 or more years ago, doesn't mean it's healthy...humans have been on a dietary experiment this whole time that has gone terribly wrong.
He also said one of my favorite statements I've heard in my 20 years of being Vegan. (and I'll repeat this later when I discuss dairy production"
...Every glass of milk has in it the blood of the mother and the tears of the calf...