Songbirds perform "tap dance"
Here I’d like to introduce some of my past findings of the courtship display in cordon-bleus, socially monogamous songbirds native to Africa.
I am currently working at Max Planck Institute for Ornithology in Germany as a postdoc researcher to study the courtship display of songbirds. I have been studying dance display of small blue finches called cordon-bleus since I was a PhD student at Hokkaido University, Japan. I study two species of cordon-bleus: red-cheeked cordon-bleus and blue-capped cordon-bleus that males have red cheek and a blue cap respectively.
A male (left) and a female (right) red-cheeked cordon-bleus.
Two female (left) and two male (right) blue- capped cordon-bleus.
My previous laboratory works revealed that cordon-bleus perform “tap dance”-like display in addition to singing.
I decided to study this bird because the courtship display has many complex and unique characteristics. During courtship, they hold a piece of nest material, and then bob up and down and sing. Interestingly, both sexes of cordon-bleus perform the song and dance displays and produce conspicuous non-vocal sounds while bobbing. Other songbirds (e.g. Java sparrows) that perform courtship bobbing do not produce such sounds, and so I expected that cordon-bleus may have some special behavioral mechanisms to produce the non-vocal sounds. To observe detailed body movements during courtship, I tried to record their courtship display with high-speed camera. As a result, I found that they stamp their feet several times against a perch in one bobbing, which is quite similar to human tap dancing.
Ota, Nao, Manfred Gahr, and Masayo Soma. "Tap dancing birds: the multimodal mutual courtship display of males and females in a socially monogamous songbird." Scientific reports 5 (2015): 16614.
The dance display is quite unique at least in two ways. First, it is surprising that “songbirds” perform such an elaborate dance display as songbirds were historically considered that they mainly communicate using songs. Probably cordon-bleus communicate via multiple modalities such as visual, acoustic, and vibration signals produced by dancing. Second, the dance display was observed in both males and females of cordon-bleus. Conspicuous sexual signals are often considered as male traits (for example, elaborate dance display and beautiful plumage in Birds of paradise and peacocks), but my behavioral analysis revealed that female cordon-bleus perform dance display as complex as males. Studying dance display of cordon-bleus might give us a hint to elucidate why some animals perform "mutual and multimodal" courtship display.
Overall, my study shed light on several overlooked aspects in animal communication. I believe that my studies of cordon-bleus will improve our understanding of the evolution and functions of complex animal communication systems.