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Animals & Wildlife

Why have we domesticated some animals but not others? It comes down to four F's.

An entertaining video explains why we can't ride zebras or breed "war bears."

Horses were domesticated over 5,000 years ago. Zebras, never.

Humans have domesticated several kinds of animals over the millennia, from trusty horses and mules to livestock for milk and meat to our favorite furry companions. But why those specific animals and not others? What is it that led us to those particular choices? Why can we ride horses but not zebras? Why don't we purposefully breed "war bears" to fight for us?

That last question comes straight from the always-interesting and often-hilarious CGP Grey, whose YouTube videos explore all kinds of things we wonder about but don't necessarily take the time to research. In the video "Why Some Animals Can't Be Domesticated," Grey explains the four main elements that make an animal a good candidate for domestication, which excludes bears (and many others) from the list.

Grey alliterated the four elements to make them easier to remember: Friendly, Feedable, Fecund, and Family-Friendly. Let's dig into what those mean.

- YouTubewww.youtube.com

Domestication requirement #1: Friendly

This one is fairly self-explanatory, but basically an animal has to not post an inherent, immediate threat. We have to be able to catch them if we're going to domesticate them, so that eliminates all of the "carnivores whose day job is murder" as Grey puts it, as well as the large, nervous prey animals that are too afraid of us to let us get anywhere near them.

wild animals, domesticated animals, gazelleGood luck trying to catch a gazelle.Photo credit: Canva

Domestication requirement #2: Feedable

Every animals is feedable, of course, but that doesn't mean it's easy or cheap to feed them, especially in large numbers. This category pretty much eliminates pure carnivores and some omnivores, leaving mostly herbivores (and some unpicky omnivores) that are easy and cheap to feed. And that aren't dangerous (see #1).

wild animals, domesticated animals, chickens, chicken feedChickens will eat just about anything.Photo credit: Canva

Domestication requirement #3: Fecund

This requirement is all about breeding and babies. Some animals are extremely slow to breed, like pandas and elephants, making them undesirable candidates for domestication. Animals that have mate frequently and have relatively short gestation times and/or large litters are more suited to domesticated life. They also need to grow up quickly, which also takes elephants out of the pool.

However, as Grey points out, humans can still tame other animals like elephants. But taming is not the same as domesticating. The basic rule is: If it's on a farm, it's domesticated. If it's in a circus, it's tamed.

Domestication requirement #4: Family-friendly

This is where the horses and zebras question comes in. Horses were domesticated in Eurasia, but if humans started in Africa, why weren't zebras domesticated first? Grey explains that while horses tend to live in hierarchical herds, zebra are more independent with no family structure. Humans can capture the lead male horse and get the rest of the herd to fall in line. Zebra herds are more of a free-for-all and they're kind of jerks to even one another.

horses, zebras, domesticated animals, wild animalsThere's actually a big difference between horses and zebras besides just the stripes.Photo credit: Canva

Barnyard animals have inherent family structures that humans have figured out how to fit into. These animals learn to see the humans who own them as a lead cow or top chicken or whatever.

Way back in the hunter-gatherer age, when humans were just figuring out animal domestication, animals had to have all four of these requirements. Today, we have the ability and technology to domesticate more animals if we want to, but we also have less of a need to. Some breeds of foxes have recently been domesticated, bred to be friendly with humans. How fun would it be to have a pet fox?

- YouTubewww.youtube.com

Technically, a lot more animals could be domesticated if people really wanted to put in multiple human lifetimes of time and effort, but why?

You can follow CGP Grey on YouTube for more fun and informative videos.

The Wildlife Conservation Society just released their favorite animal photos of the year.

The WCS is an organization dedicated to conserving the world's largest "wild places" and promoting biodiversity. They do some amazing stuff, not the least of which is taking amazing photos of wildlife from around the world.

So, as you can imagine, their top photos of 2015 from global conservation programs are pretty great:


1. This tiny lizard.

Photo by Felx Ratelolahy/WCS.

It's called a Fito leaf chameleon and it's one of the many species found exclusively on the island of Madagascar. It's also adorably tiny. Or maybe that's just a gigantic finger.

2. This baby elephant.

Photo by Dept. of National Parks, Wildlife and Plant Conservation and WCS Thailand Program.

Everyone loves baby elephants. They look like adult elephants but smaller! Plus they're clumsy and they can fly. Right? Baby elephants can fly? Am I getting that right, or did Disney lie to me again?

3. This trespassing leopard.

Photo by WCS-India/Himachal Pradesh Forest Department.

"Hey honey? I'm thinking this year we should finish building that fence. Just because of ... you know ... the LEOPARDS!"

4. This glorious snow leopard.

Photo by WCS Afghanistan.

"This is my rock. There are many like it but this one is mine. My face is itchy."

5. This funny-looking tapir.

Photo by WCS Ecuador Program.

Actually it's a normal looking tapir. This is what they look like. Stop laughing. Seriously stop. It's rude.

6. This puma who is just chillin'.

Photo by WCS Ecuador Program.

Don't you just hate it when someone takes a picture of you right as you're about to sneeze?

7. This armadillo on the prowl.

Photo by WCS Ecuador Program.

Armadillos are also the winner of 2015's Pokemon Lookalike Contest ... which is a thing I just made up. But, yay, congrats to them.

8. This jaguar in a tree.

Photo by Carlos Durican/WCS Brazil.

You little rascal, get down from there! Wait no ... don't ... never mind ... get back up there. Oh god, grab the camera! RUN!

9. This brand new species of frog.

Photo by Mileniusz Spanowicz WCS

This little guy was just discovered earlier this year in Bolivia! Apparently he had been hiding right behind scientists for years, hopping to the other side just as they turned around.

Pictures like this remind us of the importance of conserving wildlife.

They're cute and fascinating, but they also show that there's a wide variety of creatures out there sharing the planet with us. That's easy to forget.

Most of the animals featured are either threatened or endangered, and organizations like the Wildlife Conservation Society work to save not only the animals, but also the environments in which they live.

These photos are from all over the world and were taken in the wild. Which shows that WCS is pretty amazing at what they do.

For more information on the Wildlife Conservation Society, visit their website.

And to show them a little extra love this holiday season, check out their support page.