Italian scientists have managed to demystify the language of penguins and reveal that the birds have a song that caters to every occasion!
The penguins apparently vocalize to interact with colony members, parents or mates.
The study was led by Dr. Livio Favaro and the team of researchers gathered, categorized and analyzed over a hundred video, as well as audio vocal recordings of a captive colony of 48 African penguins at the Zoom zoo in Turin over a period of 104 non-consecutive days.
Moreover, the researchers also identified the behavioral contexts in which calls were made. The researchers discovered that adult penguins produce four types of basic vocalizations. They are capable of producing short calls or "contact" calls that are quite distinctive to show their isolation from mates. During fights, the adult penguins make "agnostic" calls. When the breeding season arrives, the single penguins produce an "ecstatic display song" to attract a partner and nesting partners sing a duet or "mutual display song" to each other.
On the other hand, chicks and juvenile penguins use two types of "begging calls." The first call is a cheep or "begging peeps," which the young penguins produce when it needs food. The second dubbed "begging moan" is made by juveniles when they are no longer in the nest but still require food from an adult penguin.
During vocalization, the penguin's beak is half open and it stands up, raising its neck upwards as far as possible. The sounds produced during vocalization are harmonic as well.
"Vocal communication allows us to understand the many different aspects of the biology of this species," explains Favaro. "Penguins have less sophisticated vocal mechanisms compared to song birds, but they have very sophisticated mechanisms to encode information in songs."
The African penguins create the calls through their syrinx, which is composed of two parts i.e. a set of muscles and membranes on the right and left sides. This means that several birds, along with penguins, can create two "independent signals" at one go.
Researchers, however, caution that since the colony of African penguins studied was captive, they are unsure if they were able to observe and identify all types of probable vocalizations. However, their analysis has helped establish the standardized known vocalizations, which in turn can be utilized to study the endangered species further.
"The African penguin is a highly social and vocal seabird. However, currently available descriptions of the vocal repertoire of African Penguins are mostly limited to basic description of calls," reveal researchers.
The study has been published in the journal PLOS ONE.
