"And so these sorts of behaviors are the sorts of things which might work really well when your population size is large and dense. "It's known that they collaborated in finding food, and they also collaborated in rearing young," Murray says. There's also evidence that passenger pigeons had a high rate of adaptive evolution, suggesting that they adapted to living in a large population. The Cincinnati Zoo & Botanical Garden YouTube But this new analysis suggests that's not the case. "The only difference between them is really this population size, so we can start to dig into what the evolutionary consequences of being a super-big population might be," Shapiro says.Ī genetic study done a several years ago suggested that passenger pigeons were not always super-abundant, but might have had dramatic fluctuations in population size that could have increased their vulnerability to extinction from hunting. Band-tailed pigeons are very similar to passenger pigeons, except they don't live in groups of billions. They compared the passenger pigeons' DNA to that of its closest living relatives, band-tailed pigeons, which live across the west coast of North America. "And from that," Shapiro says, "we were able to generate the entire genome sequence from several of these different birds." All the team needed was a tiny piece of skin from the bottom of one of the pigeon's toes. Museums have many other passenger pigeons besides Martha in their collections, and the researchers recently persuaded curators to let them take tissue samples from scores of the birds. Illustrated Sporting and Dramatic News/Wikimedia Commons The artwork titled Shooting Wild Pigeons in Northern Louisiana is based on a sketch by Smith Bennett and appeared in the Illustrated Sporting and Dramatic News of July 3, 1875. Her body got frozen inside a 300-pound block of ice and shipped by train to the Smithsonian in Washington, D.C., where tourists can see her stuffed body on display in a glass case. The last known passenger pigeon, Martha, lived at the Cincinnati Zoo until her death in 1914. These awesome congregations also made the birds easy to hunt, and their numbers started to decline rapidly in the late 19 th century. "There are crazy historic records about this thing blocking out the daytime sky for hours at a time," Shapiro says. "We were hoping that we could get to the bottom of why they went extinct so quickly - why it was that this giant population of birds suddenly became extinct, entirely extinct, over the course of just a couple of decades," explains Beth Shapiro of the University of California, Santa Cruz, one of the researchers on a newly released study in the journal Science.īillions of passenger pigeons once flew over North America, flocking together in huge clouds of birds. Scientists believe they may have new insights into why passenger pigeons went extinct, after analyzing DNA from the toes of birds that have been carefully preserved in museums for over a century. Her preserved body is now on display at the Smithsonian's National Museum of Natural History in Washington, D.C. Martha (right), the last known passenger pigeon, died in 1914.
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