This is Scientific Americans 60 Second Science. I'm Steve Mursky.

Coyotes. In the last two decades, they've become common in almost every North American metropolitan area.

Stanley Garrett is a wildlife ecologist at Ohio State University who studies urban coyotes in Chicago.

He spoke October 20th at the Science Writers 2014 meeting in Columbus, Ohio

about why coyotes are so good at adapting to various environments.

From a million carnivores, the 20 kilogram point 20 to

20 to 21 kilograms is the key here because mammalian predators that stay below that number can exist on prey smaller than

them and they're often solitary or they only form small groups and they can

scavenge and be able to meet their energetic needs.

But if they exceed 20 kilograms in body weight, now they have to eat prey that's their size

or larger to be able to maintain the energetic

requirements so they often are hunting prey larger than them which requires

often sociality and so that's why wolves rely a lot on deer, moose, elk, that they have to

hunt cooperatively. Some of our coyotes get right to that 20 kilogram level and

that's the perfect spot because what they can do is they can either exist

quite well on prey smaller than them and 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.

So they can do whatever they need to do as opposed to the others. You'll never see

foxes taking down prey that are their size or larger or rarely.

Well, you see that.

And you can't, 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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