Tiny Tarsiers Talk in High-Pitched Code
The Philippine tarsier is a tiny primate with a seriously high voice. The saucer-eyed mammal can let out (and listen to) squeaks and squeals at such a high frequency that it effectively gives the mammal a private communication channel.
A team of researchers found that the tiny tarsier can hear and emit sounds in the ultrasound range — that’s above 20 kHz. Most humans can’t hear in that range, and a dog whistle is pitched to be just inside ultrasound, somewhere between 22 and 23 kHz. A handful of mammals can make sounds in this range — some whales, domestic cats and a few species of bats — but few can match the Philippine tarsier. In the paper, the researchers explain that, “ultrasonic alarm calls can be advantageous to both the signaller and receiver as they are potentially difficult for predators to detect and localise.” Being able to hear in high ranges might let them eavesdrop on noises made by moths, crickets and birds.