Scientists have rewound 65 million years of evolutionary history by twerking chicken DNA to create embryos that grow alligator-like snouts rather than beaks.
By Nick Collins, Science Correspondent
7:30AM BST 18 Aug 2011
Chickens and other birds are thought to have descended from dinosaurs through a series of genetic changes.
But by altering the DNA of chicken embryos in the early stages of their development, scientists are able to undo the progress made by evolution and give them qualities they lost millions of years ago.
Ethical regulations prevent the eggs from being hatched but Arhat Abzhanov, an evolutionary biologist based at Harvard University in America, said he hopes to one day to complete his work by turning chickens into Maniraptora, small dinosaurs believed to have spawned 10,000 species of birds.
The ability to rewind evolution also raises the prospect of fast-forwarding the same process to create species which are designed to adapt to Earth's changing climate, and eliminating birth defects in human children, it was claimed.
Scientists believe that modern birds lost their snouts in the cretaceous period, instead developing beaks in one of a number of changes that distances them from other relatives like alligators.
But by altering parts of their DNA to resemble alligator genes before the beak began to develop, Dr Abzhanov and Harvard University graduate student Bhart-Anjan Bhullar were able to alter the development of chicken embryos so that they grew snouts instead.
The growth of embryos is governed by signalling molecules, which switch on certain genes controlling the development of limbs, organs and other body structures.
By altering the signalling patterns, the researchers prevented the embryos from developing beaks and instead caused them to grow snouts.
Disclosing the research group's preliminary results at a seminar in July, reported by the New Scientist magazine, Dr Abzhanov said: "It looks exactly like a snout looks in an alligator [at this stage]."
Jack Horner, a leading paleontologist based at Montana State University, is conducting a similar project aimed at developing a "chickenosaurus" with a tail and hands similar to those of a dinosaur.
If scientists are able to turn the process around and speed up evolution, they could create species better adapted to the changing planet.
Craig Albertson, a developmental biologist from the University of Massachusetts, has already crossed two blue fish from different populations to create red offspring – a possible evolutionary trait making it easier for males to attract females in murky, polluted water.
Understanding exactly how genetic signalling works could also help doctors prevent birth defects such as cleft palate from developing in the womb, it was claimed.
Jill Helms, a stem cell biologist based at Stanford University in California, said: "I can envision a day when we eliminate such defects in the womb."