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1 .<-NARRATOR:->Listen to part of a lecture in an archaeology class.
1 .<-FEMALE PROFESSOR:->In our last class we began talking about animal domestication, and we said it's [slowly] the process whereby a population of animals is bred in captivity and becomes accustomed to being provided for and controlled by humans.
2 .[Pause, seeing a raised hand] Question, Jim?
1 .<-MALE STUDENT:->Yeah, I was thinking.
2 .You said domesticated animals usually served some kind of purpose for humans.
3 .Like horses could, uh... pull heavy loads,and dogs could hunt or herd sheep.
4 .But cats? Why were they ever domesticated?
5 .[Slight laugh] I mean, mine can't do much of anything!
1 .<-FEMALE PROFESSOR:->Interesting question.
2 .Cats don't seem likely candidates for domestication, do they?
3 .They actually lack an important characteristic that most animals that can be domesticated have: domesticable animals tend to live in herds or packs, with clear dominance hierarchies.
4 .Humans could easily take advantage of this hierarchical structure.
5 .By supplanting the alpha individual, they could gain control of the whole group- or of individuals, as in the case of dogs.
6 .Cats in the wild, though, rarely have this structure.
7 .For the most part, they're solitary hunters.
1 .But... as for their utility to humans?
2 .Well, it's helpful to think about when and where cat domestication might've begun.
3 .Any ideas, Jim?
1 .<-MALE STUDENT:->Well, I'd guess ancient Egypt?
2 .I'm thinking of all those ancient Egyptian paintings of cats...
1 .<-FEMALE PROFESSOR:->Good guess [even though you’re wrong…]-those paintings you mention do provide the oldest known depictions of full cat domestication, where cats are without question household companions.
2 .The paintings, from about 3,600 years ago, typically show cats in Egyptian homes poised under chairs, sometimes wearing collars,eating scraps of food out of bowls....
3 .But the Egyptians don't get credit for the early stages of cat domestication, where cats are just beginning to interact with humans.
4 .There're signs of early domestication as far back as 9,500 years ago.
5 .Recently, two graves were discovered on the island of Cyprus.
6 .One was the grave of a human, buried with some tools, sea shells, and other items.
7 .And, nearby, a cat was buried in its own grave.
8 .Interestingly, the cat's body was oriented in the same westward direction as the human's body.
9 .Another notable thing about the two bodies was that they were in an identical state of preservation, suggesting they'd been buried at the same time.
10 .So we can assume that humans had at least some kind of relationship with cats as early as 9,500 years ago.
1 .<-MALE STUDENT:->So cat domestication began in Cyprus?
1 .<-FEMALE PROFESSOR:->Well,[I can see how you might think that] except cats weren't native to Cyprus.
2 .They were undoubtedly brought over to the island by boat, probably from the nearby coast of the Fertile Crescent, in the Middle East.
1 .In fact, extensive DNA analysis has now confirmed what archaeologists have believed for quite some time:all modern domestic cats arose from just one subspecies of wildcat from that single location,the Fertile Crescent,and not from any of the other four subspecies of wildcat located in other areas throughout the world.
2 .Pretty amazing, isn't it?
1 .Which brings us back to Jim's question: why did it happen? And how?
1 .Well, for years researchers have pondered this question of cat domestication, and the best I can do here is just a theory... [Slight laughter; expecting students to agree that the theory makes sense]
2 .But tell me it doesn't make sense!
3 .In evolutionary terms, early settlements and agriculture in the Fertile Crescent around 10,000 years ago,created a completely new environment for any wild animals that were flexible and curious enough to exploit it.
4 .Mice were attracted to these settlements, and cats, being obligate carnivores- they must eat meat to thrive- they were almost certainly drawn to the settlements by the mice.
1 .Over time, only the cats that could adapt to living in human-dominated environments would've stayed and thrived.
2 .People probably encouraged them to stick around and control the mice in the fields and the granaries, and eventually their homes.
3 .And perhaps simply grew to like their company, too.
1 .<-MALE STUDENT:->Hmm... . So in a way, the difference with cats was that domestication was their idea instead of ours!
2 .[Thinking] But... why do you suppose only one of the five subspecies was domesticated?
3 .Were the others just, um... [short pause, thinking] not friendly enough toward humans?
1 .<-FEMALE PROFESSOR:->Well, no... in fact, at least two of the other subspecies are known to be relatively friendly.
2 .But the Fertile Crescent subspecies had... well, a head start,because of its proximity to the first human settlements.
1 .And as agriculture spread, the tame ancestors of this subspecies spread with it.
2 .So they filled the niche of home companion in each region they entered- and effectively shut out the local subspecies that were already there.