A team of researchers coordinated by paleontologist Bhart-Anjan S. Bhullar, from Yale University, and biologist Arhat Abzhanov, from Harvard University, has identified and recreated the molecular processes that made the snouts of some dinosaurs transform into the beaks of the first birds. In this way, these experts managed to get chicken embryos to develop the snout and palatal configuration that they presented, for example, the Velociraptors – the well-known bipedal predators that popularized the film Jurassic Park – or the primitive Archeopteryx birds, which lived 150 million years ago. years old and retained characteristics of some feathered dinos.
As these scientists explain in the journal Evolution, to find the molecular mechanism related to the anatomical constitution of the beak, they carried out an analysis of the fossils in which it is possible to appreciate its formation and looked for possible changes in gene expression that correspond to that process. Thus, they focused mainly on embryos of emus – large flightless birds that live in some areas of Oceania – alligators, lizards and turtles. Paleontologists realized that in their early stages of embryonic development, the great lineages of birds present a unique gene expression, related to the configuration of the facial regions, different from that which characterizes reptiles and mammals.
The scientists used inhibitors to suppress the activity of the proteins involved, thereby inducing the appearance of an ancestral anatomy. Not only did they manage to reverse the structure of the beak, but they also made the palatine bone, located at the back of the face, show archaic characteristics. The discovery of this molecular mechanism could allow the identification of the transformation associated with it in the fossil record, which, in Bhullar’s opinion, opens the doors to an important advance in our knowledge of evolutionary history .
