City Mice Are Smarter Than Country Mice

Country mice may be twice as nice, but city mice may be getting smarter because urban animals are learning to adapt to humans and the changes we make to the wild landscape, according to a new study.

Biologist Emilie Snell-Rood measured the skulls of 10 species of small animals—like mice, shrews and bats—collected over 100 years at the Bell Museum of Natural History at the University of Minnesota.

Snell-Rood found that in at least two species—the white-footed mouse and the meadow vole—the brains of animals from cities or suburbs were about six percent bigger than the brains of animals collected from farms or other rural areas.

In rural parts of Minnesota, two species of shrews and two species of bats experienced an increase in brain size as well, leading the researchers to conclude that as the country mice, voles, shrews and bats became city mice, voles, shrews, and bats, their brains became significantly bigger.

The brains of all six species have gotten bigger because humans have radically changed Minnesota, Snell-Rood told the The New York Times on Thursday.

Where there were once pristine forests and prairies, there are now cities and farms. In this disrupted environment, animals that were better at learning new things were more likely to survive and have offspring. Animals colonizing cities and towns have to learn how to find food in buildings and other places their ancestors hadn’t encountered, Snell-Rood said.

We had to wonder: Are bigger-brained animals necessarily a good thing? In my neighborhood north of Boulder, Colorado, black bears have learned to open car doors, climb inside, and carefully pick leftover kid snacks and food wrappers from non-edible contents.

And what about this grizzly, who didn’t invent the wheel but has figured out how to take advantage of mobile dumpsters?

Researchers are interested in building on Snell-Rood’s study by breeding small-brained animals with their larger-brained cousins, and give animals tests to see just how much life in a human-dominated world has changed how their brains work.

Sounds cool in an animal that weighs just ounces and fits in your palm. But imagine if Snell-Rood or other scientists could work that kind of magic up the evolutionary line?

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Original article from TakePart