Vocal production learning in mammals revisited

Area of Science:

• Zoology
• Animal Behavior
• Bioacoustics

Background:

• Vocal production learning is well-documented in songbirds but less explored in mammals.
• Previous reviews on mammalian vocal learning provide a foundation for current research.
• Understanding vocal learning in mammals is crucial for comparative studies of communication.

Purpose of the Study:

• To review and synthesize evidence for vocal production learning and vocal convergence in mammals over the past 25 years.
• To update existing knowledge on the occurrence and extent of vocal learning across diverse mammalian groups.
• To identify gaps in current research and suggest future directions for studying mammalian vocal learning.

Main Methods:

• Comprehensive literature review of studies on mammalian vocal learning published in the last 25 years.
• Analysis of evidence for vocal production learning (copying novel sounds) and vocal convergence (adjusting sound parameters) in various mammalian species.
• Examination of experimental methodologies and recommendations for future research.

Main Results:

• Clear evidence of vocal production learning in cetaceans, pinnipeds, elephants, and bats, including imitation of artificial and human sounds.
• Wider evidence of vocal convergence in primates, mole-rats, goats, and mice, indicating adjustments in vocalizations between individuals.
• Mechanisms underlying vocal convergence remain unclear, with possibilities including vocal production learning, usage learning, or matching physiological states.

Conclusions:

• Vocal learning and convergence are more widespread in mammals than previously recognized, occurring across multiple orders.
• Further experimental research is needed to elucidate the mechanisms and limitations of vocal learning in different mammalian species.
• Standardized quantitative methods are essential for confirming vocal learning and differentiating it from other forms of vocal adjustment.