Lions roar, elephants trumpet - but what do giraffes do? Biologists have speculated for years about whether giraffes can vocalise, or whether their long necks prevent them from producing the necessary airflow. After reviewing almost 1000 hours of sound recordings from three European zoos, Angela Stbger at the University of Vienna, Austria, has an answer. Her microphones picked up a low hum from the giraffe enclosures at night. At about 92 hertz, the sound is just within the lower limit of human hearing (BMCResearch Notes, doi.org/7rt). Giraffes have a structured social system, and for a long time scientists have been trying to figure out how they communicate, says Meredith Bashaw at Franklin & Marshall College in Lancaster, Pennsylvania. 'This new vocalisation could add a piece to that puzzle," she says.
展开▼
