'Terror birds' had deep voices, fossil suggests

A 90%-complete "terror bird" skeleton found on an Argentinean beach suggests these big-beaked predators had good low-frequency hearing and deep voices. It is the most complete skeleton ever discovered for one of these menacing beasts, and represents a new species. Scientists have even been able to reconstruct the shape of its inner ear. This offers clues about the animal's hearing, which was probably lower than that of modern birds and suggests they used low-pitched calls to communicate. The find is reported in the Journal of Vertebrate Paleontology. Argentinian palaeontologists made the discovery in the cliffs of La Estafeta beach, not far from the popular tourist city of Mar del Plata. Federico Degrange, one of the study's authors, said dealing with the tide had presented a challenge. "The sea can actually take the fossil and destroy it in the sea. It's a nice place to work, but you have to be fast," he told BBC News. Terror birds, or "phorusrhacids", were the top predators on the South American land mass in the era following the dinosaurs' extinction some 65 million years ago.READ MORE-http://www.bbc.co.uk/news/science-environment-32218542