Maybe Charles Darwin didn't have to sail all the way to the Galapagos islands after all.
While evolution is often thought of as playing out in the wilds of the natural world, as it turns out, urban environments are a major hotbed for species adaptations. Over centuries of development, cities have rewritten the rules of survival for the organisms that live there -- and researcher is beginning to prove that some critters are just learning to cope, they're actually undergoing genetic change.Baruch College scientist Jason Munshi-South has spent the last several years studying this phenomena of urban evolution in New York City -- particularly when it comes to the white-footed mouse.
A population of these small rodents has lived in the city's few remaining forested areas, isolated from their countryside counterparts in more rural parts of the state. Munshi-South had a hunch that the naturally selecting factors for the city mice might have spurred genetic changes over time that made them distinct from the others. So, he collected DNA from both city and rural mice in hopes of spotting any differences:
Here's a rundown on the findings, from the National Geographic:
They found a handful of genes in the city mice that appear to have evolved due to natural selection. The functions of these genes are, in many cases, exactly the sort that you’d expect to evolve in a city mouse. Some of them are known to be involved in recognizing pathogens, and others help launch an immune system attack against them. Others help to detoxify pollutants. These genes not only evolved relatively quickly–in just the past couple centuries at most–but also repeatedly. In park after park, the same adaptations were favored by natural selection.
There's no doubt that life is resilient to change, but the rate of human urbanization can at times seem too rapid and too unnatural for other organisms to keep pace. But as Munshi-South's proves that the urban jungle and the jungle jungle really aren't so different in terms of evolution.