It is very common to have a bird feeder in your backyard because a lot of people enjoy watching birds up close right from a window, but recently it has been found that this simple act is actually starting to split a certain species of bird in two, according to Martin Schaefer. The Central European Blackcap Warbler is a small bird that spends its summers in southern Germany and Austria. These bird's migration routes are genetically determined and they normally naturally fly 1,000 miles south to Spain in the winter where it is warmer and there is more food.
Over the past 50 years, this natural routine has changed, now 10% to 30% of the species fly, believe it or not, northwest 360 miles to the U.K. for winter. They have been doing this because they are able to find plenty of food supplied by humans in the form of seed and suet. Since the flight from the U.K. to Germany is so much shorter than the fight from Spain to Germany, the birds coming back from the U.K. arrive sooner which makes them more likely to mate with each other. This is causing the birds to develop different characteristics and is called reproductive isolation. Some of the identifying characteristics of the U.K. warblers are shorter rounded wings which allow them to maneuver better without having to fly as far as the spain migrating birds. They also are developing smaller and skinnier beaks because they do not need to eat large fruit and olives. The European Warblers have not split into two different species yet, but could possibly if these changes keep happening and people keep feeding the birds like they are. When the U.K. birds and Spain birds are unable to successfully mate anymore is when they will officially be two different species.
Since we have been studying Darwin and evolution in class i thought this study was very relevant. It shows how much of an impact we are having on our planet that by simply feeding birds we can possibly create a new species. this also shows how delicate our planet is. This study is also interesting because of how fast these changes in the birds are happening. The articles said that the birds started migrating to the U.K. in the 1960's which is only about 50 years ago. Darwin believed that it took much longer than this for a species to change so much, but he probably wasn't taking into account the effect we humans have on other species. I am a strong believer in the theory of evolution so this study makes perfect sense to me and i believe that it is legitimate.
My primary source was an article from Wired magazine. The information from Softpedia was based off of the Wired article so it was virtually the same, just constructed differently. The article from U.S. News and World report was different from the Wired article in that is talked about genetics more. Even though all three of my sources were very similar, I found Wired to be the most straight forward and since I trust Wired magazine for giving me dependable information, I liked it the best.
"How Feeding Birds Splits Them into New Species - The process is being observed by scientists - Softpedia." Latest news - Softpedia. Web. 07 Dec. 2009. <http://news.softpedia.com/news/How-Feeding-Birds-Splits-Them-into-New-Species-128859.shtml>.
Keim, Brandon. "Feeding Birds Could Create New Species." Wired. 3 Dec. 2009. Web. 6 Dec. 2009. <http://www.wired.com/wiredscience/2009/12/bird-feeding-evolution/>.
Milius, Susan. "Bird Feeders, Migration Change May Split a Species." US News and World Report. 4 Dec. 2009. Web. 6 Dec. 2009. <http://www.usnews.com/science/articles/2009/12/04/bird-feeding-migration-change-may-split-a-species.html>.
No comments:
Post a Comment