TULSA, Okla. (CBS Houston) – Researchers recently discovered that birds have, over the course of time, evolved into having shorter wings in order to avoid being hit by cars.
According to the New Scientist, an estimated 80 million birds lose their lives each year to traffic incidents, with cliff swallow populations taking especially large hits in the area. However, the number of deaths, at least for the cliff swallows, has been steadily decreasing over the past 30 years, despite an increase in nests located near roads.
One scientist may have found out the reason why.
Charles Brown of the University of Tulsa has been studying cliff swallows for the past 30 years, both by examining specimens captured in mist nets and those found dead on streets, New Scientist is reporting.
Through his research, he noticed a distinct difference between the length of the wings of birds killed by motorists, and the wing span of those caught in nets.
Brown also reportedly observed an overall decrease in the length of their wings over the course of this three-decade career.
New Scientist learned from Brown that unseasonable cold in May 1996 may have also affected the growth of the birds, in addition to killing off a significant percentage of the area population.