Giant South American river turtles that live in the Amazon have much more complex social behavior than it was thought until now, wrote biologists in the journal Herpetologica.
During the breeding season the giant river turtles gather in large groups. Until now it was not clear how they coordinate their behavior. Biologists now believe that acoustic signals help them in this.
Scientists have recorded 270 different sounds that the turtles produce on the shore or swimming in the river. After spectrographic analysis, they divided the sounds of six types.