Baby Crocs Speak from Within Egg

Scientists who study crocodiles have long noted the calls, perfectly audible to humans, emitted from Nile crocodile eggs soon before hatching. But until now, those calls had never been definitively deciphered by humans. New research indicates that the hatchlings' calls--which researchers say sound like "Umph! Umph!"--appear to alert their nest mates that it is time to hatch. Croc mothers, who bury their nests as soon as the eggs are laid, are also spurred into action by the sounds; the calls signal to the mother that she should begin digging up her young.