In the highland cloud forests of Central America, high-pitched melodies often ring out through the underbrush. But these melodies are not from the songbirds who flit amongst the branches. Instead, they belong to the Alston’s singing mouse, Scotinomys teguina, a tiny creature with a surprising skill.
These small rodents, which weigh between 10 and 13 grams, are known to “sing” complex, tuneful calls to communicate with one another, particularly during moments of territorial dispute.
The high-pitched songs of the Alston’s singing mouse are often heard before the mice are seen. Unlike other vocal rodents that tend to chirp or squeak, Scotinomys teguina sings structured melodies that vary in pitch and rhythm, akin to bird songs.
Each call serves a purpose, from attracting mates to warning competitors. These acoustic signals are crafted with intricate timing. They are regulated by brain regions similar to those that manage human speech and songbirds’ musical notes, making this little rodent an intriguing subject for both biologists and neuroscientists.
Why Do Alston’s Singing Mice Sing?
Alston’s singing mouse vocalizations serve a variety of social functions. Males sing more frequently than females, primarily to stake out and defend their territory, according to a January 2011 article published in Hormones and Behavior. When two males from different territories come close to each other, an interesting interaction unfolds: a “sing-off.”
A “sing-off” is a competitive duet that lets each mouse gauge its rival’s strength without escalating to physical confrontations. Singing possibly allows these mice to avoid injury and conserve energy, as aggressive physical encounters in the wild can be quite costly.
What’s particularly striking is that these singing duels rely on precise timings. Researchers have found that Alston’s singing mice have specialized neural circuits that help them start and stop singing within milliseconds of hearing a rival’s song.
This rapid timing suggests an advanced level of auditory processing, revealing just how crucial these vocalizations are in the social interactions of the Scotinomys teguina. This ability to coordinate vocal exchanges closely mirrors conversational turn-taking in humans, an impressive feat for an animal so small.
How Alston’s Singing Mice Produce Their Songs
The vocalizations of Alston’s singing mice are high-pitched and rapid, lasting for about a second, with 15-20 notes in each song. Their pitches are so high, that most of these sounds are at the upper end of the human hearing range, which is part of why they are so effective in the dense, noisy, high-altitude forests they call home.
Scotinomys teguina produce their songs using fast, precise movements of their vocal cords, suggesting that their brains contain specialized cells that allow them to adjust pitch and timing on a moment-to-moment basis, according to a March 2019 article published in Science.
Another study uncovered that the neural mechanisms behind these mice’s vocalizations share striking similarities with human speech circuits. This, in turn, suggests that despite the evolutionary gap between humans and Alston’s singing mice, certain brain regions associated with vocalizations and communication may be conserved across species.
Singing As A Survival Strategy
Singing does more than help Scotinomys teguina establish boundaries. In the humid cloud forests where they live, predators like Neotropical wild cats and birds of prey are an ever-present threat. By vocalizing in short, high-pitched bursts, they can make themselves heard without lingering in the open or attracting too much attention. This type of “hit-and-run” singing approach is thought to be a bioacoustic adaptation to avoid predation, allowing them to quickly assert their presence before returning to safety.
Furthermore, singing plays an important role in mate attraction. Females can discern different songs and appear to prefer certain tones and tempos, meaning males with particularly well-tuned songs may have an advantage. By selecting males with desirable songs, female singing mice contribute to the evolutionary pressure shaping the species’ vocal abilities.
This makes the song of Alston’s singing mice a dynamic adaptation, honed over generations to fit the ecological demands of their environment.
Scientists Are Studying These Mice Closely
Alston’s singing mice continue to be a subject of fascination for scientists interested in communication, behavior and neuroscience. Their unique vocalizations offer valuable clues into the evolution of communication in mammals.
For one, studying their songs could improve our understanding of human speech disorders, since the neural circuits that allow them to sing are in some way analogous to those used by us. As research progresses, these tiny crooners could help us uncover new insights into how complex communication systems develop, both in animals and ourselves.
These singing mice offer unique insights into animal communication, song learning and even the evolution of language. Despite their size, they present a case study of how complex communication can emerge in the most unexpected places.
As scientists continue to unravel the mechanics and purposes behind their vocal abilities, they are discovering a highly adaptive form of communication that reflects cognitive processes rarely found in the rodent world.
The coordinated exchanges between Alston’s singing mice are almost humanlike and the mechanisms behind their vocalizations share similarities with human speech circuits. Does this make you feel as a part of a bigger whole? Take this test and find out: Connectedness to Nature Scale.
