Eerie wails pierce the morning calm of lowland rainforest in eastern Madagascar and are soon joined by more. The haunting cries are the song of the indri – a critically endangered, metre-tall lemur. Now research suggests the primate’s calls have a great deal in common with human music.
Indris (Indri indri) sing to communicate with other family groups, or to locate and reunite with family members, says Chiara De Gregorio at the University of Turin in Italy. But the degree of rhythm in this soulful keening and the calls of other primates isn’t well understood. So De Gregorio and her colleagues started dissecting the indri’s song.
The researchers recorded songs from 20 different indri groups over 12 years in Madagascar’s rainforests and analysed the timing of the notes.
