Vocal mimicry is a feature of vocal learning, or the ability to learn vocalizations from family members and social companions. As humans, vocal learning allows us to learn language from our family and peers. But this cognitive ability is not unique to humans. Other mammalian species, as well as many avian species, also rely on this form of social learning for vocal communication. These vocal learning species are distant evolutionary relatives of humans, and include whales, bats, elephants, seals, parrots, songbirds, and hummingbirds.

Vocal learning has been identified in different species using observations of vocal mimicry, such as parrots mimicking human speech, or an orca whale that could produce human words. Vocal learners can also be identified by babbling behavior, such as baby bats that babble in a manner similar to human babies. In other species, vocal learning abilities have been confirmed by identifying vocal dialects, or vocalizations shared within social groups or geographic regions, similar to regional dialects that are common across human languages. For instance, young bats can learn vocal dialects within colonies, and captivity can influence parrots’ vocal dialects compared to wild populations. Sperm whales exhibit dialects in their codas, or series of clicks shared within clans. In one bat species, scientists trained individuals to mimic experimental vocalizations. Recent research suggests that vocal learning abilities could be detected across more mammalian species by assessing the pitch of vocalizations.

Why and how did vocal learning abilities evolve? And why did vocal learning evolve in species distantly related to humans? Birds with vocal learning abilities share similar brain regions with humans, suggesting that the neuroanatomy necessary for vocal learning arose by convergent evolution. It is possible that the neural circuits for vocal learning originated from the neural circuits that control motor movements, a hypothesis known as “the motor theory of vocal learning origin”. If so, then species that rely on social learning of vocalizations should also exhibit social learning of motor movements. For instance, males of one hummingbird species socially learn both songs and dances (see this video of male hummingbirds displaying). You can check out this video for more discussion about the evolutionary origins of vocal learning. The evolution of vocal learning may also be linked to the social environment, as discussed in this TEDxUCLA talk about language, social interactions, and the brain. Complex social environments may be linked to the evolution of brains that can process complex social information, as shown in these vocal communication experiments with freely interacting Egyptian fruit bats.

Parrots’ ability to learn vocalizations has contributed to their popularity as pets, which has influenced the decline of many species in the wild. Check out this interview from one of the authors of the book Parrots of the Wild for more information about parrots’ evolutionary history and behavior, the conservation status of different species, and how parrots are adjusting to habitats altered by human activity. For more discussion of how parrots’ behavior in the wild is linked to the many challenges of keeping parrots in captivity, you can watch the PBS Nova Episode Parrot Confidential. The documentary website has interviews and clips that provide a short summary, including some thoughts from Jane Goodall. The World Parrot Trust has podcasts about parrot conservation, including how identification of individual palm cockatoos can aid conservation efforts, and a road ahead for parrot conservation. You can also learn more about other conservation projects developed with local communities across the Americas, such as the Mesoamerican Parrot Census Network targeted towards yellow-naped amazons (listed as a critically endangered species in 2021), and projects underway with different parrot species in Central and South America.

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