In 2009, the world’s most famous paleontologist made a bold claim. In “How to Build a Dinosaur,” Jack Horner proposed re-creating a small dinosaur by reactivating ancient DNA found in its descendants, chickens. His 2011 TED talk on the subject went viral. And then for the past four years, the public heard nothing.
While the Internet moved on to other viral videos and ideas, Horner and his team have been working on the “chickenosaurus” and moving ahead the science of evolutionary development. The project has already resulted in some of the first research into the embryonic development of tails.
The idea that birds are descended from dinosaurs is no longer questioned within the mainstream scientific community. Paleontologists have long studied the changes in bone structure of dinosaurs and birds over time. Meanwhile, molecular biologists have studied the composition of modern bird genes. By merging these scientists’ work, Horner, who is curator of paleontology at the Museum of the Rockies in Bozeman, Mont., hopes to answer questions about evolution.
Horner’s premise can be viewed from the launchpad of the late Michael Crichton’s novel and film “Jurassic Park,” a story that involved obtaining dinosaur DNA from undigested blood in mosquitoes preserved in amber. The idea of finding dinosaur DNA this way was taken seriously by many people, and the possibility was explored by scientists.
Jack Horner knows the “Jurassic Park” theory very well, having served not only as the inspiration for one of the main characters but also as a technical adviser for the film. But 24 years after the novel was published, we have yet to find any DNA in mosquitoes from the time of the dinosaurs.
DNA degrades under even ideal storage conditions. Cool, sterile conditions can extend its useful life to as long as perhaps a few million years, and dinosaurs disappeared about 65 million years ago. No matter how perfect a mosquito we find in a blob of amber, we cannot make a dinosaur out of that mosquito’s last blood meal.
There
is only one way that DNA has been proved to survive millions of years
relatively intact: by replicating itself during that time. This is
exactly what happened as birds evolved from dinosaurs.
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