A newfound dinosaur could provide clues to the birds’ beaks.

Credit: Yu Chen
Artist’s depiction of the Limusaurus inextricabilis, which was found to have lost its teeth in adolescence.

Chinese scientists have identified the first known dinosaur species that had teeth as a young animal and then lost them in adulthood.

The finding may explain why birds have beaks, according to the study authors. They have studied the fossils from a small dinosaur called Limusaurus inextricabilis, belonging to the theropods, the evolutionary precursor to modern birds.

This dinosaur is believed to have eaten meat as young but developed into a vegetarian diet as adults.

The results are based on fossils from 13 dinosaur specimens discovered in northwest China. The different fossils have enabled the researchers to follow the development from newly hatched dinosaur to an adult animal at the age of ten.

The study has been published in the journal Current Biology

Reference:

Shuo Wang7, Josef Stiegler, et al. Extreme Ontogenetic Changes in a Ceratosaurian Theropod dx.doi.org/10.1016/j.cub.2016.10.043