Something to think about: there are nearly 6000 species of mammals (i.e. animals that produce milk), yet 97% of our dairy products come from cows. Crazier still is that in the United States, there are really only three types of dairy commercially available: sheep, goats, and cows. I have always been told that pigs produce delicious milk, but that their body type prevents effective milking (although this cartoon makes the process seem pretty easy). It seems a bit too silly to be true.
Other countries have slightly more variety. Buffalo (water and otherwise), yak, elk, reindeer, and even horse milk is consumed internationally, but none of it at the rate of cows milk. Why?
"Cow's milk has some real aesthetic and practical advantages: It separates itself into cream and milk, so it can be made into an easily drinkable beverage as well as all the luscious cream-based comestibles, such as ice cream and crème fraîche. Its fat content is similar to that of human milk, which makes it familiar to our palates, and its relative blandness makes it an attractive blank slate for the creation of cheeses with a range of flavor profiles and consistencies, from runny Camemberts to rock-hard Goudas."
Because of the practical advantages to cows milk, it has never had any real competition - except for certain types of cheeses. Still, I am waiting for the day when I walk into my local organic market to pick up some pig's milk cheese (or better yet, hampster's milk cheese). I am certain that foodies would be all over that one.
Others' Milk from Slate