City Living May Shorten Some Birds' Natural Lifespans

So stressful here!

A great tit
A great titAndreas Trepte | CC BY-SA 2.5

Sure, the monotonous smoggy slog of city living might get you down. But if you're a great tit, it might be slowly killing you.

Scientists at Lund University in Sweden compared birds that had urban-dwelling parents to bird babies from the countryside. They took blood samples and compared the length of their telomeres.

We humans have telomeres too, strands of DNA that sit at the ends of our chromosomes. Telomeres are like "the plastic tips on shoelaces" according to the University of Utah Health Science's Department website, because they keep chromosomes from sticking together or from fraying. Every time a cell divides it loses some of the ends of its telomeres, until the telomere gets so short the cell can no longer divide. People think telomeres have something to do with how we age.

So, back to the great tits (whose name you should add "bird" to before sticking in a Google search at work). Science Magazine reports:

They found that great tit chicks raised in urban environments had shorter telomeres, on average. Regardless of their birthplace, city-raised chicks’ telomeres were 11 percent shorter than those of chicks raised in the countryside, the team reports today in Biology Letters.

The authors don't know how the phenomenon might relate to us as humans, and don't get scared yet. 11 percent isn't an enormous difference, and the researchers don't know the cause, but guess it could be related to stress from city pollution. We think it might be from the great tit parents stressing about looking cool, staying out all hours of the night and smoking cigarettes with their friends. Who knows?