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1 .This is Scientific American's 60-Second Science. I'm Steve Mirsky.
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2 .Coyotes. In the last two decades they've become common in almost every North American metropolitan area.
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3 .Stanley Gehrt is a wildlife ecologist at Ohio State University who studies urban coyotes in Chicago.
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4 .He spoke October 20th at the ScienceWriters2014 meeting in Columbus, Ohio, about why coyotes are so good at adapting to various environments:
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5 ."For mammalian carnivores, the 20-kilogram point, 20 to 21 kilograms, is the key here.
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6 .Because mammalian predators that stay below that number can exist on prey smaller than them.
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7 .And they're often solitary or they only form small groups.
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8 .And they can scavenge and be able to meet their energetic needs.
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9 ."But they exceed 20 kilograms in body weight, now they have to eat prey that's their size or larger to be able to maintain their energetic requirement.
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10 .So they often are hunting prey larger than them, which requires often sociality.
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11 .And so that's why wolves rely a lot on deer, moose, elk, that they have to hunt cooperatively.
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12 ."Some of our coyotes get right to that 20-kilogram level,
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13 .that's the perfect spot, because what they can do is they can either exist quite well on prey smaller than them,
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14 .that's typically what they do, or if they have to, if the conditions dictate it, then they can hunt and consume prey larger than them.
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15 .So they can do whatever they need to do.
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16 .As opposed to the others, you'll never see foxes taking down prey that are their size or larger, or rarely will you see that.
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17 .And you won't see wolves living off of really small prey, rodents, for any length of time, they will temporarily but not for a long time.
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18 .So this kind of sets the stage for the perfect predator here.
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19 ."Also, being in the middle means that they are also subjected to predation at times by the larger predators such as wolves and mountain lions, and the occasional bear.
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20 .So they have to be extra good at hunting their own prey as well as not becoming prey themselves.
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21 .So it creates a super-smart animal."
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22 .For Scientific American's 60-Second Science. I'm Steve Mirsky.
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