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  • There’s about 7.4 billion people on Earth today

  • ...and over 200 million dogs.

  • So exactly where, when, and why did warm-hearted wolves join our pack?

  • And who trained who?

  • [OPEN]

  • So

  • Cat person?

  • Or dog person?

  • Me?

  • I’m totally impartial.

  • No matter where you sitsiiiiiiit, it’s plain to see that the histories of dogs and

  • humans are intertwinedmaybe like no other two species.

  • If we take domestication out of the human equation, it’s estimated just 1 or 2 million

  • of us would be around today.

  • And of all those animal alliances, our relationship with dogs is the oldest.

  • But figuring out why, where, and when domestic dogs first originated is still a bone of contention.

  • Why?

  • Is the easiest to answer.

  • Every continent is home to wild canidslike Africa’s painted dogs or Asia’s doles,

  • but thanks to genetic research we know modern pups didn’t descend from those local species.

  • Today’s domestic dogs all trace their DNA back to ancient wolves.

  • You may have heard that wolves and ancient people were hunting buddies that used teamwork

  • to run down bigger prey.

  • That’s a nice story, but wolf packs can hunt just fine on their ownand usually

  • aren’t too big on sharing.

  • Plus, early humans tended to kill off most carnivorous competition.

  • It’s most likely that humans didn’t adopt dogs.

  • Dogs adopted us.

  • Anywolves gone mildthat were tolerant of humans could have scrounged our scraps.

  • They didn’t need us, but our leftovers could have made their lives easier.

  • Today, about 85 percent of domestic dogs still survive on our waste - no matter how many

  • times we tell themSTAY OUT OF THE TRASH

  • But a tame wolf isn’t a dog, and scientists are still trying to figure out when and where

  • that change occurred.

  • Studying living wolves tells us the line that led to our pups is extinct today, but we can

  • still find their footprints in modern dog genomes.

  • Looking at DNA in mitochondria tells us dogs split from their wolf ancestors somewhere

  • in Europe between 19 and 32 thousand years ago, but whole genomes from dozens of living

  • dogs put the split somewhere in South Asia around 33,000 years ago.

  • It’s tough to pin down because dog genes have mixed so much.

  • Fossils don’t tell the whole story either, because bones alone can’t tell us when the

  • thing that looked like a wolf started to act like a dog.

  • But combining the two, fossils and DNA, could give us some hints.

  • DNA extracted from ancient dog fossils has suggested a new story: the domestication split

  • happened in two places, at least 12,000 years ago.

  • And then at some point, Eastern dogs followed people west, and became the dominant ancestor

  • of our canine compadres.

  • Dogs became useful herders, sled pullers, and guardsagainst predators AND neighboring

  • human tribes.

  • And in a pinch, they could have served as an emergency food supply.

  • Dogs probably saved us more times than we can count.

  • Were paying them backpups now have access to insurance, healthcare, some even

  • have more instagram followers than you and me.

  • From a wolf mold, weve crafted 340 or so dog breeds, even a few weird ones.

  • It’s hard to believe every domestic dog is still part of the same species, one whose

  • story is so tightly wound to our own, that we still can’t quite tell where it begins.

  • Stay!

  • Staaaay.

  • Curious.

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B1 中級 美國腔

狗和人類。30,000年的友誼(英尺,MinuteEarth) (Dogs and Humans: A 30,000-Year Friendship (ft. MinuteEarth))

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    erry 發佈於 2021 年 01 月 14 日
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