The Fascinating World of Urban Evolution

In a feature piece, Brendan I. Koerner dives into the work of scientists studying the evolution of urban wildlife. From oysters to rats to coyotes, animals have adapted to cities in ways that offer useful insight into survival at the genetic level.

"Rather than wilt away as Homo sapiens have spread forth bearing concrete, bitumen, and steel, a select number of species have developed elegant adaptations to cope with the peculiarities of urban life: more rigid cellular membranes that may ward off heat, digestive systems that can absorb sugary garbage, altered limbs and torsos that enhance agility atop asphalt or in runoff-fattened streams," says Koerner.

One researcher, for example, found that pigeons in New York are able to exist on a steady diet of discarded foods high in refined sugars without becoming hyperglycemic. Another researcher discovered that lizards in Costa Rica from cities had different physiologies than those in the forest that allowed them to move faster and avoid predators and more extreme heat.

And what these researchers are learning, says Koerner, is important as climate change puts more stressors on wildlife. These findings can inform conservation efforts, but they can also point to ways evolving species can help address the environmental issues humans have caused.

"If we can peer deep into genomes and identify the species most likely to develop the specific traits we crave, we can place those animals in environments where natural selection will do the dirty work of shaping them into long-term survivors," notes Koerner.