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  • If you've had a cup of coffee with cream lately, or maybe cereal with milk, you've

  • come to the right place.

  • Because, while you may not have thought of it then, milk is weird.

  • Well, the liquid itself isn't that weird. It's super useful.

  • But the way that we use it? That's weird.

  • I mean, milk is for babies. That's why it was made.

  • Plenty of adult humans drink it anyway, like myself, and the milk we drink mostly comes

  • from cows.

  • But there are lots of other options out there -- including the fattiest and skimmest milks known.

  • You just probably wouldn't want to drink them.

  • Milk is produced by modified sweat glands in mammals called mammary glands, and it's

  • used to give baby animals the nutrients they need before they can digest other food.

  • All mammals produce milk--it's where we get the name Mammalia, and it's one of the

  • three defining features of mammals, along with hair and three middle ear bones.

  • Humans, being mammals, also make and drink milk.

  • But we've done something no other animal has:

  • We've taken this nutrient-rich baby food and, through genetic mutation, turned it into

  • a digestible, dietary staples for humans of all ages.

  • But most people don't continue to drink human milk throughout their lives.

  • If they did, it would mean a human would have had to sacrifice the calories necessary to

  • make the milk, which would have totally defeated the purpose back when we were starting to

  • use it as an extra source of nutrients.

  • So instead, we drink the milk of other animals.

  • People around the world drink milk -- and make other food products from -- animals like

  • yak, reindeer, water buffalo, elk, and horses.

  • In the US and Europe, dairy consumption is mostly limited to the mammary secretions of

  • sheep, goats, and cows.

  • But really, mostly cows.

  • Why? Well, first, picture a cow. They're big and they're pretty nice.

  • Over generations of selective breeding, we've created creatures who can give between six

  • and seven gallons of milk a day, and they're domesticated enough to just line up to do it.

  • Goats and sheep, while they've also been bred to produce more milk and be more willing

  • to do so, can only produce about a gallon of milk a day.

  • By economics alone, cows are the better milk producers.

  • But it's also a matter of taste.

  • Cow's milk has a fat content similar to human milk -- about 3.5% versus a human's

  • 4.5% -- which makes it familiar, at least if you want to drink whole milk.

  • By comparison, the water buffalo, which produces the milk that gives the world buffalo mozzarella,

  • has a fat content of almost 7 percent -- great for cheese, but maybe not the best for drinking.

  • These animal milks all have different fat content, because it depends on the animal's

  • environment and the way that they nurse.

  • If you're looking for the very fattiest known milk, you'll have to find a hooded

  • seal -- their milk is about 60% fat.

  • That's because hooded seal pups are born on floating sea ice in the North Atlantic

  • and Arctic oceans.

  • The harsh temperatures and the instability of the environment mean that the pups have

  • to put on a lot of fat really fast. They only nurse for about four days, but almost double

  • their weight in that time.

  • By comparison, heavy cream is usually around 36% fat.

  • Even if you wanted to hang out in the freezing, icy ocean, drinking this stuff would be like

  • trying to drink really fatty peanut butter.

  • At the opposite extreme, the skimmest known milk comes from the black rhinoceros, with

  • a fat content of around 0.2%.

  • The watery milk probably has to do with their long nursing period: black rhino moms nurse

  • their young for almost two years, and pouring a ton of fat into their milk for that long

  • would use up a lot of resources.

  • But if you wanted to try some out, you might have some trouble tracking it down.

  • For one thing, black rhinos are critically endangered, so it would be tough to find one

  • in the first place.

  • And even if you did find oneit's still a rhinoceros.

  • Have you seen one of those things?

  • About a third of the females and half the males die from fights with other animals.

  • Unless you're a baby rhinoceros, a nursing rhino mom is probably not going to let you

  • walk up and take a swig.

  • Now, before we sign off, I want to clear up one milky myth that gets repeated a lot.

  • Hippopotamuses are mammals, and they make milk.

  • You may have heard that it is pink, but it is not.

  • Hippo milk is whitish, just like all other milk.

  • This misconception probably comes from the fact that hippos do secrete a super useful

  • mucus on their skin that helps protect against UV rays and works as an antibiotic.

  • And the mucus is a reddish color.

  • But it is not milk!

  • Though, again, you probably wouldn't want to go up to a hippo and check.

  • Thank you for watching this episode of SciShow, which was brought to you by our patrons on

  • Patreon. If you want to help us spread more tasty science, you can go to

  • And don't forget to go to and subscribe!

If you've had a cup of coffee with cream lately, or maybe cereal with milk, you've

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Extreme Animal Milks You Probably Don't Want To Drink

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    joey joey posted on 2021/05/05
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