Bird Feeders Are Speeding Up Evolution?
Filed Under: Environmental News on December 7, 2009
Apparently so, according to some research being done in Germany. Scientists are finding that some species of birds are actually evolving into separate, distinct species thanks to bird feeders changing their natural habits. This is interesting, as it could change how science views evolution and is proof that animals can adapt more quickly to changes in their environment than previously thought.
The study, done at the University of Freiberg, shows that Central European Blackcap Warblers have split into two separate reproductive groups. One group is behaving as Warblers always have, migrating and pairing with little change in habit. The other group, comprising about 30% of the population, has changed and no longer migrates, staying put in their various European homes thanks to humans giving them food through the winter.
This change has happened in only about 30 generations, must faster than would have been expected. Further, birds in Britain have evolved distinctively different beaks and wings, no longer having to fly as far and subsisting on a diet heavier in seeds and nuts. Thanks to bird feeders.
The two groups of Blackcaps are now two isolated reproductive groups, which means their splitting will evolve even further with time.
Historically, all Warblers have migrated from Germany and Austria down to Spain for the colder months. Any bird staying too far north would die of starvation. Winter territory has changed, however, taking about 360 miles off of their 1,000 mile flight to Spain twice a year.
The split that is staying north, going to Britain instead of Spain, have developed more rounded wings, which aren’t as suited to long flight, but are better for maneuvering. Their longer, narrower bills have adapted to eating their human-provided diet and are no longer very good tools for eating Spanish winter olives.
While the whole evolutionary process may take 100,000 or more years, Dr. Martin Shaefer of the University says he is astounded at the speed with which the evolution is taking place. “It shows the profound impact of human activities on the evolutionary trajectories of species.”
Fascinating idea, hard to believe but it seems like the science is there.