Scientists are able to reproduce the molecular process which led to first bird beaks made from dinosaurs snouts using fossil records as a guide. This represents the first successful reversion to a bird’s skull characteristics. Harvard developmental biologist Arhat Abzhanov, Yale paleontologist, and developmental biologist Bhart–Anjan S. Bhullar led the research team. They used ancestral molecular evolution to create chicken embryos that had a dinosaur-like snout. The specimens also had a similar palate to those of Velociraptor and Archaeopteryx, which are two small dinosaurs. They joked that their specimens were not called ‘dino-chickens’ when they published the details in Evolution, an academic journal. In the laboratory, scientists traced the beak of the bird back to its dinosaur roots. Yale Image. Prof. Bhullar, the lead author said that the goal was not to make a dinosaur out of a bird. Scientists, writers, and the general public have been searching for a way to reproduce elements of the dinosaur’s physiology. The film ‘Jurassic World,’ as well as Jack Horner’s 2009 book titled ‘How to Build a Dinosaur’ have featured it. In this instance, the researchers were particularly interested in how the beak relates to bird anatomy. Professor Bhullar pointed out that bird’s beak was crucial to avian food. To generate an hypothesis about the transition, they first did quantitative analyses of similar fossils and animal anatomy. They then looked for changes in gene expression which could be correlated to the transition. Professor Bhullar, along with his colleagues, looked at the gene expression of embryos from turtles, lizards alligators, and emus. Dinosaurs are the ancestors of birds. The major bird lineages, the common neognaths which are virtually all flying birds, and the less common paleognaths which are mostly non-bird reptiles, differ from other major linesages – turtles, lizards, and crocodiles. They also found that birds have a median gene expression zone with two distinct facial development genes, unlike previous studies in chickens. Researchers were able induce ancestral molecular activity as well as ancestral anatomy using small-molecule inhibitors. These inhibitors blocked the protein activity produced in the chicken-specific median signaling area. Researchers reversed bird’s beak. Not only did it restore the structure, but also the function of the median signaling zone in chicken embryos caused the palatine bone to return to its original state. Professor Bhullar stated that this was an unexpected result and showed how a simple development mechanism could have broad-ranging, unexpected consequences. The group then relocated from southern Louisiana’s Rockefeller Wildlife Refuge to Massachusetts and set up an emu farm. In their search for specific gene expression, they extracted DNA from multiple species to create clones of fragments. Professor Bhullar said that the results of this study have many implications. Prof. Bhullar said that the study has several implications. Professor Bhullar stated that Hesperornis, which was discovered by Othniel Marsh of Yale Peabody Museum of Natural History, is an example of a close relative of modern birds. It has a beak that is fused to the premaxillae (small bones at the tips of most animal’s upper jaws) and is then enlarged for birds. Professor Bhullar suggested that their approach could be used to examine the developmental processes behind several evolutionary changes. Citation: “A molecular mechanism to explain the origin of an important evolutionary innovation, bird beaks and palates, discovered by an integrative approach for major transitions and vertebrate evolution,” Bhart–Anjan S. Bhullar and Zachary S. Morris. Elizabeth M. Sefton and Jasmin Camacho. Arhat Abzhanov. Evolution. DOI: 10.1111/evo. 12684.
