Quirks and Quarks

Shrinking Coyotes

Coyotes have adapted since the Ice Age by becoming smaller and changing their behaviour.
Calgary coyotes are carriers of a tapeworm that can be dangerous if ingested by humans. (U.S. Fish and Wildlife Service)
Coyotes are a wildlife success story, in that they've been able to adapt to human disturbances better than nearly any other large predator, living in and around us everywhere we go. But that's at least in part because they're a shadow of their former selves.

According to Dr. Julie Meachen, an anatomist and paleontologist from Des Moines University in Iowa, fossil coyotes from the last Ice Age show an animal quite different from the coyote of today. Ancient coyotes were more robust, with stronger, thicker jawbones, teeth adapted for tearing meat and bringing down large prey, much as wolves do today.

Dr. Meachen thinks that the extinction of many large herbivores, and competition from newly arrived Eurasian grey wolves, put pressure on the coyote to downsize, and the "new and improved" coyote is the one we share North America with today.

Related Links

- Paper in PLOS One
Live Science story