I Am Milk!

Milk everyone’s first drink

- Kate Lowenstein and Daniel Gritzer

If you are a mammal, and I assume you are (Hello!), we are already well acquainted, aren’t we? I was, after all, your first food. I am the sweet secretion that flows from the mammary glands of a mammalian mom, the perfect nutrition for a baby human, cow, dog—what have you. I’m what allows an infant creature to exit its mother’s body and still continue to get everything it needs from her to grow into a larger, intelligent (in your case) being, tremendously jam-packed as I am with protein, fat, and delicious sugars.

The big twist with you humans, of course, is that you figured out how to continue your habit of drinking me well beyond your infancy and into adulthood. And rather than collect human milk and bottle it up, you chose a more efficient lactating creature to supply you: the cow.

This was an udder stroke of genius. By domesticating a milk-supplying animal—actually, over history, a bunch of them, including sheep, goats, buffalo, camels, and yaks—you found a way to take advantage of otherwise nutritionally useless grasslands and pastures. Ruminants such as cows, sheep, and goats are equipped with multiple stomachs and the (somewhat impolite) habit of regurgitating and re-chewing the contents of those stomachs until they’ve squeezed out every last nourishing molecule. With this unrivaled digestive determination, these beasts manage to turn scraggly weeds into copious amounts of rich and creamy me—and more.