Cliff Swallows Are Evolving to Avoid Cars

Allison Guy
March 29th 2013

Cliff swallows, as their name suggests, like to build nests on cliffs and other rocky outcroppings. They also like building their nests on bridges and overpasses, and sunbathe on warm roads. This puts them in the path of traffic, and adds thousands of swallows to the nearly 80 million birds killed by cars each year in the US. Swallows in the state of Nebraska, however, appear to be getting wise to the ways of the highway – or at least their genes are.

Researchers at the University of Nebraska have been collecting swallow bodies along several highways for the last thirty years. Not only have the total number of fatalities decreased over this time, but the wing length of the birds has also been decreasing. The swallows, it seems, are evolving to become more nimble. Shorter wings makes it easier to take off vertically or to quickly maneuver around vehicles. Time to add "vehicular selection" to the sub-categories of "natural" selection.

Via Smithsonian Magazine. Photo via Nebirdsplus.

Share your thoughts and join the technology debate!

 

Comments are members only. Login to your account and join the technology debate.

LOGIN
Not a member? Join us

Should men be able to give birth to children?


Joyce Nabuurs: To me this question seems to be a logical next step in the emancipation movement of the past century. More and more women entered the workspace, but the responsibility for pregnancy and childrearing remained female.

Comment
Already a member? Login.