According to fable attributed to Aesop, there was once a country mouse who invited his cousin who lived in the city to come visit him…If you do not know that story, it is easy to find. The moral of that story seems to be that peace and quiet in the country ultimately provide a better life than the dangers of the city, no matter the attractions of the latter.  Hard to argue with that, unless you are a city mouse at heart.  And/or if your mouse brain has been hardwired that way. In which case, you can thank the tendency of humans to transform the natural environment into built space. Carl Zimmer explains recent scientific findings along these lines:

Evolutionary biologists have come to recognize humans as a tremendous evolutionary force. In hospitals, we drive the evolution of resistant bacteria by giving patients antibiotics. In the oceans, we drive the evolution of small-bodied fish by catching the big ones.

In a new study, a University of Minnesota biologist, Emilie C. Snell-Rood, offers evidence suggesting we may be driving evolution in a more surprising way. As we alter the places where animals live, we may be fueling the evolution of bigger brains.

Dr. Snell-Rood bases her conclusion on a collection of mammal skulls kept at the Bell Museum of Natural History at the University of Minnesota. Dr. Snell-Rood picked out 10 species to study, including mice, shrews, bats and gophers. She selected dozens of individual skulls that were collected as far back as a century ago. An undergraduate student named Naomi Wick measured the dimensions of the skulls, making it possible to estimate the size of their brains.

Two important results emerged from their research. In two species — the white-footed mouse and the meadow vole — the brains of animals from cities or suburbs were about 6 percent bigger than the brains of animals collected from farms or other rural areas. Dr. Snell-Rood concludes that when these species moved to cities and towns, their brains became significantly bigger.

Read the whole article here.