It seems that every day we discover yet another aspect of nature that is amazing. Even some of the smallest mammals are showing some remarkable resiliency. We are certainly aware of the persistence of the human spirit, but the animal spirit is pretty persistent too.
If we visit New York City enough and spend our time there, we will not be very surprised at what we see. We might see lines that extend for an hour just to get a bagel and other crazy things. There are even some mummified bat corpses hanging in alleys right behind book stores and the like. And then there is the human feces sitting on a floor insider a subway station. And we all know this is pretty much the kinds of things we expect to see there.
Are Mice Really Evolving?
But the amazing news comes from New York’s tinier, hairier citizens—aka its mice—who are adapting to the city environment in a scientific way, in other words, in an evolutionary way. A research team evaluated the genomes of some white-footed mice that were collected in New York and also from some parks that are adjacent to New York to determine if they have indeed evolved as a result of the stresses and the pressures of living in the city. As it just so happens, it seems that these little urban critters are most likely adapting genetically to these new city diets. And this might even include pizza and cheeseburgers.
“Human infrastructure causes habitat loss and fragmentation and changes resource availability, novel species interactions occur because human movements and commerce introduce a diverse array of nonnative species, and human activity increases exposure to chemical, light, and noise pollution,” the authors of the study reported in their summary which was published for the first time last year, but has been recently updated. “These changes lead to unique pressures in novel urban habitats that may rapidly drive evolutionary change over short timescales.”
Researchers Study Urban and Rural Mice
The scientists collected some 24 mice from three different city locations, which include Central Park, Flushing Meadows, and the New York Botanical Gardens. They also gathered an additional 24 mice that came from more rural areas like the Hudson Valley, the Long Island’s Northeastern end, and New Jersey’s Kittatinny Mountains. The scientists then went about extracting, sequencing, and finally analyzing genetic material from their livers for evaluation.
They actually discovered less genetic diversity within the city mice as opposed to the rural mice. The researchers also found some small changes in a few specific genes pertaining to mice digestion within those from the citys. “Our evidence suggests that the evolution of mitochondrial and metabolic processes has been important to the success of P. leucopus living in NYC’s urban forests,” the researchers noted.
Generally speaking, these results are raising the possibility that these mice have evolved because of the lowered quality in their urban diet, even though the food is plentiful. One of the researchers believes that their diet is too high in cheeseburgers and pizza. However, another researcher feels that this observation is a function of what insects and plants are available to the mice.
However, all the researchers agree that the sample sizes were probably too small to make a definitive conclusion and that more data is needed. They like the idea that they potentially have a chance to study evolution as its occurring.