Birds evolve to dodge traffic Sly swallows fly on little wings, study finds Does a new study offer a bird's-eye iew into evolution? Fewer cliff swallows are being illed by moving vehicles because of volution, says a study published today the journal Current Biology, "These birds have been exposed to ehicles and roads for 30-plus years," aid Charles Brown, the study's lead uthor. "During that time, they have volved to avoid being killed by traffic. volution can happen very rapidly, and orne animals can adapt to urban envi- onments very rapidly." The decrease in road deaths is likely ecause these birds have shorter wing- pans, making them more agile fliers r they are learning to avoid vehicles, rown said. . An estimated 80million birds are illed by colliding with vehicles on U.S. oads each year, according to a 2005 .S.Forest Service report. . In the western U.S., cliff swallows, hich live in colonies, have nests ound highway bridges, overpasses d road culverts. They sit on roads to ·ck up gravel for their gizzards tohelp ·gest food and to sunbathe. The road kill index decreased from out 20 cliff swallows a year at the art of the study in 1983in Nebraska to estimated two birds a year. by the. udy's end in 2012.' . This is only an estimate of those led because more died but were not und, The drop can't be explained by de- . es in the bird population or in traf- , the study suggests. The birds that ntinue to die on the roads have longer · gspans. Wing lengtbs vary between ~--------~~~--------------~--~----~~~'-.---- By Cathy Payne USA Today. Cliffswallows sit at their nest in Nebraska. The birds have become less likelyto get hit by cars, USA TODAY WILY CRITTERS Charles Brown, the study's lead author, said cliff swallows do learn from watching others so some' may figure out how to avoid on- coming traffic. "Birds that have the ability to learn are more likely to survive and produce more babies," he said. "Overtime, the pop- ulation will have smarter birds." 4.1inches and 4.5 inches, Brown said. "Longer-winged swallows sitting on a road probably can't take off as quick- ly,or gain altitude as quickly as shorter- winged birds, and thus the former are more likely to collide with an oncoming vehicle," said Brown, a professor of biological sciences at the University of Thlsa. Geoff LeBaron, an ornithologist with the National Audubon Society, says shorter wingspan would allow cliff swallows to turn more quickly to avoid being hit by vehicles. "If the long- er-winged birds are the ones being clobbered, then the shorter-winged. birds are the ones passing on genes to the next generation;" said LeBaron, the society's Christmas Bird Count direc- tor, who was not involved in the study. The study also found that the aver- age wing length is shorter. In the 1980s, . the average was 4.3 inches; it dropped to 4.1 inches in the late 2000s, Brown' said. Sim~n's.4-teens-only mall policy Isn't the solution . T~e recent decision by the I ~. :~l~~ Metropolitan Police Dep~rt~~nt group~~~~~~~~Z to~rUfe~~~reak up C.astlet~n~quare Mall is ridicul~~~sa~d dI~~pPofmtmg.In a city.that offers no f o~IOns or teens to gather with their rtends the m 11' h . th '. a ISt e only place with e ex~eptlOn of a school or a pla~e of worshIp, th~t young people are able to meet up. This new policy will al ate an th . so ere- o er opportumty for prOfiling of young people. Willmall security break ~fr~~~~tP ofbfivewell-behaved white mall :will~1e °b YS gO.toa I?ovie at the , ey e split up into two r{~ffl~i~KLs~curityif they want to go to me. d The real issue that should be ad- y~~~~~~ ~a~~~~~f;t~~~~,~i~~Se~~ft~r ~ssue at the mall, more security guards l·ho~ld be p~es~nt. A policy that further ~I s o~ kIds. options for enjoyment SO':I. setting and increases the prol;>abIlIty~fracial and gender profil- ~~~~~~~l~g. There is a rational way the mall I hIf1creased safety issues at J " F' - Ire more security. u Ie orean Carmel ------------------~