si-banded-mongoose

The banded mongoose makes a call that lasts between 50 and 150 milliseconds and is comparable to one syllable, say scientists. (University of Zurich)

Some animals are more eloquent than previously thought and have a communication structure similar to the vowel and consonant system of humans, according to new research.

Studying the abbreviated call of the mongoose, researchers at the University of Zurich have found they are the first animals to communicate with sound units that are even smaller than syllables and yet still contain information about who is calling and why.

Usually, animals can only produce a limited number of distinguishable sounds and calls due to their anatomy. While whale and bird songs are a little more complex than most animal sounds — in that they are repeatedly combined with new arrangements — they don’t pattern themselves after human syllables with their combination of vowels and consonants.

Studying wild banded mongooses in Uganda, behavioural biologists discovered that the calls of the animals are structured and contain different information — a sound structure that has some similarities to the vowel and consonant system of human speech.

Banded mongooses live in the savannah regions of the Sahara. They are small predators that live in groups of around 20 and are related to the meerkat.

The scientists recorded calls of the mongoose and made acoustic analyses of them. The calls, which last between 50 and 150 milliseconds, could be compared to one "syllable," the researchers found.

But they also found that even one long "syllable" contained what might be called "segregated vocal signatures."

"The initial sound of the call provides information on the identity of the animal calling," said David Jansen, a member of the research team.

The second part was more tonal — similar to a vowel — and indicated the caller's activity at the time.

The researchers, lead by biologist Marta Manser, say they believe other animals are capable of having more intricate call structures too.

"So-called simple animal sound expressions might be far more complex than was previously thought possible," concluded the report published in BMC Biology journal.