Spontaneous rhythm discrimination in a mammalian vocal learner
Laura Verga1,2, Marlene G U Sroka3,4, Mila Varola1,4
1Comparative Bioacoustics Research Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.
Biology Letters
|October 26, 2022
Summary
Harbour seals, a mammalian vocal learning species, can spontaneously discriminate rhythm patterns in conspecific calls. This finding supports the hypothesis that vocal learning may be linked to rhythmic abilities in animals.
Area of Science:
- Animal Behavior
- Bioacoustics
- Comparative Psychology
Background:
- Rhythm and vocal learning are fundamental to human music and speech.
- Vocal learning is hypothesized to be a prerequisite for rhythmic capacities.
- Few mammals, besides humans, exhibit flexible, spontaneous rhythm discrimination.
Purpose of the Study:
- To investigate spontaneous rhythm discrimination in harbour seals (Phoca vitulina), a mammalian vocal learning species.
- To test the rhythm-vocal learning hypothesis by examining seals' responses to rhythmic variations in conspecific calls.
Main Methods:
- Exposed twenty wild-born harbour seals to playback sequences of conspecific calls.
- Varied basic rhythmic properties including call length, sequence regularity, and tempo.
- Monitored seals' reactions, specifically the number and duration of looks, as indicators of discrimination.
Main Results:
- Seals demonstrated significant reactions to changes in call length, sequence regularity, and tempo.
- These reactions indicate spontaneous discrimination of rhythmic properties in the auditory stimuli.
- The findings suggest a capacity for rhythm perception in a non-primate mammalian vocal learner.
Conclusions:
- Harbour seals possess spontaneous rhythm discrimination abilities.
- This supports the hypothesis linking vocal learning and rhythmic capacities.
- Pinnipeds offer a valuable model for studying the evolution of rhythmic abilities across species.
