A large proportion of vocal mimics are songbirds, otherwise called ossine passerines, which are bird species that actively learn vocal signals called songs. Other birds, known as “suboscines”, do not show vocal mimicry, except for a few species, such as parrots and hummingbirds.
Due to their innate ability to learn songs, songbirds are very skilled in picking up vocalizations of various types. Thus, songbirds have well-developed mimetic abilities.
In the 1930s, scientists noticed that male songbirds were better at mimicry than female birds. This led them to believe that vocal mimicry developed as a result of vocal learning practiced by male birds in order to attract females for mating. Furthermore, male songbirds mimic mostly during the mating stage of their life, confirming that vocal mimicry has developed as a byproduct of song learning.
How Did Mimicry Skills Emerge?
It is common sense to assume that a singer with a broader vocal range will be more successful than one with a smaller vocal range. Similarly, male songbirds with the vocal learning ability to learn broader types of songs enjoy higher chances of mating success. Therefore, songbirds started acquiring broader song learning skills through evolution. Eventually, these songbirds ended up with vocal skills so broad that they could not just learn songs from other males in their species, but songs from different species too.
Thus, vocal mimicry skills emerged in songbirds as a byproduct of vocal learning.
Vocal Mimicry In Parrots
Parrots have been maintained as pets for thousands of years, and are probably the most famous mimics, apart from songbirds. Vocal mimicry in parrots has often caught human attention, since they can mimic the complex vocalizations of human speech learned from their caretakers.
The reason for this is neither to attract mates nor to repel predators, as was previously thought by scientists. Parrots raised as pets often mimic humans to initiate social bonding, and they mimic other species in the wild for the same reason.
Parallels Between Mimicry In Parrots And Human Language
In a study on an African Grey parrot, scientists observed that it could not just mimic human speech, but could also learn several hundreds of words, their meanings, recognize objects by names, and even count! The study has made scientists think that parrots are not simply mimicking, but that their vocal ability is very similar to that of human speech.This is a huge discovery, as humans are the only animals known to be capable of using “language” to date, but this study revealed that parrots possess many abilities seen in humans, such as the ability to recognize rhythm and counting.
Parrots are one of the most popular vocal mimics kept in captivity by humans. Although they’re not songbirds, parrots efficiently mimic complex human vocalizations learned from their caretakers. Through numerous studies, scientists have come to understand that parrots mimic to increase social bonding with human caretakers. However, scientists are unsure as to why and how vocal mimicry evolved in these suboscines or “non-songbird” species, and whether it developed independently in the evolutionary chain to the similar skill of songbirds.