Which other mammal besides humans is known to have a sense of rhythm?
And the answer: Indri lemur.
Indri lemurs are the only lemurs that communicate using songs. Previously, this trait was only found in humans and birds.
Found only on the island of Madagascar, the Indri is a large species of lemur that evolved without pressure from other primate species. Without facing competition, the island produced a diverse range of different species. Locally, the Indri is known as the babakoto, which means "little father" or "ancestor of man." Native populations believe that the Indri (with its lack of visible tail) resembles their ancestors, and thus receives some protection in parts of their native environments.
Indri lemurs use rhythm in their vocalizations, making them the only mammal besides humans known to do so. While all kinds of mammals make different sounds and calls, not all possess rhythm, which is defined as the patterns and structure found in recognizable music. Researchers recently recorded the cries of indri lemurs in the jungles of Madagascar. After analyzing recordings of 636 calls, they found that lemurs sing in rhythms common to human music. The team has not yet discovered the evolutionary benefits of singing in patterns, but they think it makes it easier to gather younger lemurs and to defend their territories. Other ideas suggest that it could help young indris learn the songs, which is important when family groups need to communicate.
Although humans and indris are the only known mammal species to have a sense of rhythm, but those lineages diverged over 77 million years ago, when dinosaurs still roamed the planet. This means that, more likely, the knack for music likely evolved independently after the lineages split.
Learn more about the Indri lemur here.