Mice serenade each other with love songs in the hope of attracting a mate and females prefer a tune that has a nice rhythm
- Female mice were played recordings of male mice singing courtship songs
- Some of the tracks played to the mice were natural recordings and others edited
- The edited tracks included artificial stuttering, skips and order changes
Mice serenade each other with love songs in the hope of attracting a mate and females prefer a tune that has a nice rhythm, a new study finds.
Researchers at University College London played female mice recordings of male mice singing a ‘love song’ and monitored how they responded to the sounds.
They found that the females cared more about the rhythm of the noise, which is sung at ultrasonic frequencies, than about the order of the ‘words’.
The team played the mice real recordings as well as digitally altered versions with the mice reacting badly to the addition of ‘stuttering’ to the courtship tune.
A Couple of Harvest Mice seen in this stock image. The team found mice used song like ultrasonic vocalisations to attract a mate
The team also found that rate that mice ‘sing’ is roughly the same as the way other mammals speak – including humans and monkeys.
The study, which has not yet been peer-reviewed, is grounded in other research that found male mice produce whistle like rhythmic vocalisations.
This new research expands on that and plays those ‘courtship’ noises to female mice to track their reactions and see what it is about the songs they like.
‘Scientists sometimes make assumptions about how animals perceive the world without considering their natural behaviour,’ said lead author Dr Catherine Perrodin.
‘Here, we asked the mice directly what components of mouse love songs they are interested in – they showed us what matters to them by approaching the sources of the sounds they liked best’.
The researchers presented the mice with real recordings as well as others that were modified to change particular dimensions.
In some of the recordings they changed the rhythm (temporal regularity), syllable sequence or the qualities of the syllables themselves.
‘We found that female mice are very sensitive to disruptions to the songs’ rhythmic regularity,’ said Dr Perrodin.
‘They dislike irregular, artificially ‘stuttering’ versions of courtship songs. Changing the syllable structure or sequence didn’t seem to matter to them as much.’
Animals navigating the real world face a barrage of complicated sounds which their brains have evolved to compress and filter for sounds relevant to survival.
An example of this is communication signals, for both social interactions and a number of mammals use acoustically complex vocalisations.
Little is known about what information listeners take from the sensory streams and so they examined how mice respond to one time of sound.
The researchers presented the mice with real recordings as well as others that were modified to change particular dimensions (stock image)
Dr Perrodin said mouse songs share similar features with human speech, in that they follow a similar rhythm when vocalised.
‘By studying animal communication, we are learning which acoustic features of vocal sounds mammals care about, that their brains might prioritise.’
The team found that female mice selectively listen for the rhythm of male songs when listening for someone to mate with.
They hope to be able to take what they’ve learnt from studying reactions to mouse song and apply it to how the brains of humans evolved the ability to communicate.
A non-peer-reviewed pre-print of the paper has been published on BioRxiv.
WHAT DO WE KNOW ABOUT WHALE SONG?
For a long time it was believed that whales sang solely for mating purposes.
But some experts suggest the songs also help the mammals explore their surroundings.
Researchers have recorded humpback whales changing their calls when they move to new pastures in order to match the songs of others around them.
Learning these songs may help whales pinpoint one another and group together better when in unfamiliar waters.
Researchers have recorded humpback whales changing their calls when they move to new pastures in order to match the songs of others around them (file photo)
It is tricky for scientists to study how whales sing, as the shy beasts are notoriously difficult to observe, and each species vocalises differently.
Humpback whales sing using folds in the vocal box that vibrate at low frequencies as air is pushed over them.
It has been suggested they have special air sacs adjoining these vocal chords which connect to the lungs.
These allow the whales to pass air between their lungs, the sacs, and the vocal chords without losing any of their precious air supply.