An increase in brain size was also detected in two species of shrews and bats
Well, chalk one up for homo-sapiens, sort of. While we've known for some time that humans have been affecting the enviroment on a global scale, one aspect of our evolutionary impact on other species might not be all bad.
In a recent study, University of Minnesota biologist Emilie C. Snell-Rood found evidence suggesting that our direct changes to the natural habitats of animals (through technologies advances, antibiotics and revised food pyramids) have caused some animals to evolve with bigger brains.
Dr. Snell-Rood studied dozens of individual animal skulls, some as old as a century, from ten different species including bats, gophers and mice. In two of the species, the white-footed mouse and the meadow role, the brains of the animals plucked from metropolitan areas or suburbs were about 6% bigger than those of the animals taken from farms or other rural areas. Dr. Snell-Rood's hypothesis after assessing the first wave of results was that brains become significantly bigger when they move to cities or bustling towns, where the animals must learn to find food in places that they're not biologically trained to encounter or expect.
