The indri is the only lemur that sings, and its wailing choruses carry for long distances through Madagascar’s rainforest. Now researchers have worked out part of how it manages such power: it uses a technique that opera singers spend years learning.
Smithsonian Magazine reports that a team led by Filippo Carugati of the University of Turin analysed 83 video recordings of 19 wild indris in the Maromizaha forest and the Mitsinjo reserve. Using motion-tracking software, they followed the animals’ lips frame by frame and found that the lemurs open their mouths wider as the pitch rises. Sopranos do the same thing, a method known as formant tuning, to keep high notes loud and clear.
The study, published in PLOS Computational Biology with colleagues at the University of Warwick and Sapienza University of Rome, suggests the trick helps indri songs cut through dense vegetation. It is also a neat case of convergent evolution: the lineages leading to humans and indris parted company about 74 million years ago, and each arrived at the same solution on its own.
Source: Smithsonian Magazine