ST. ETIENNE, France, June 25 (UPI) -- French scientists say they've discovered baby crocodiles communicate with each other and their mother while they are still in their eggs.
The researchers say they've determined the pre-hatching calls of baby Nile crocodiles tell the others in the nest it's time to hatch. The cries, the scientists said, also tell the mother crocodile to begin digging up the nest.
The findings, made from a series of "playback" experiments, confirm what had only been suspected on the basis of prior anecdotal observation, according to researchers Amelie Vergne and Nicolas Mathevon of Jean Monnet University in St. Etienne, France.
"We can well suppose that hatching synchrony can be of vital importance for crocodiles," Mathevon said. "Indeed, most mortality occurs early in life and hatching vocalizations might well attract predators. Therefore, adult presence at the nest and its response to juvenile vocalizations may offer protection against potential predators.
"In this sense, it is important for all embryos in the nest to be ready for hatching at the same time so that they all receive adult care and protection," he added.
The research appears in the journal Current Biology.