Need help with creating a presentation for my Animal Behavior class in which we discuss different species and its behavior and how it helps them in their living habitat. The project is basically creat

Song and dance has a way of captivating the hearts and imaginations of people young and old, and birds are excellent at both of these displays. Take the renowned dance of the Japanese crane, an elegant duet that has long since immortalised itself in Japanese culture as a symbol of longevity in marriage. The crane has been featured in many documentaries, books and is a common motif in Asian design. Vocal duets are also prominently portrayed in popular media, the scienti c literature and human cultures - namely species like duetting penguins, other seabirds such as albatrosses and traditional songbirds like wrens.

Researchers have been tapping in to the hidden dances of the cordon bleu birds, who, as it turns out, tap their feet at such high speeds a special camera was needed to see them. Miya Warrington explores their multi-modal displays. Tapping their own Tappin song to the beat of BEHAVIOUR W © Nao Ota 62 - BIOSPHERE BIOSPHERE - 63 resolution of [human] visual/auditory senses, it was hard to tell which bird was the best ‘tap-dancer’ with our naked eyes and ears,” research team leader, Masayo Soma, told Biosphere Magazine.

Viewing the recordings in slow motion, the team discovered that each head bob was accompanied by multiple very rapid (~ 10 milliseconds) foot-steps, and that singing was interspersed in between the headbob-footsteps. This tap dancing, referred to as step-dancing by the researchers, has never been seen in songbirds before, although it has been observed in non-passerine (non-song) birds such as bustards and rails.

So, why dance, in addition to singing? What is the inherent bene t to these birds? Consider the common celebrity-gossip-topic, discussing artists that dance and lip sync at the same time, to the disappointment of fans that expect a fully original multimodal concert. As these artists (or rather their publicists) point out, the physical demands of dancing and singing are great, and this is no exception for these multi-talented cordon-bleus. The elaborate physically demanding dance performance of the cordon-blue may be, in fact, a signal that plays an important role in intersexual communication.

To answer this question, the authors set about further analysing the high speed recordings of the dance displays, taking care to Traditionally it was thought that these elaborate male signals evolved as a result of sexual selection, in which a male displays his quality as a mate by the complexity, synchrony, or quality of his display. The use of more than one modality, like combining dance and song, aids in enhancing the potency of their intended signal. The male brown-headed cowbird (Molothrus ater) is one such bird with an elaborate courtship display consisting of both song and dance. A previous study showed that females were more enticed by playbacks that included both visual and acoustic signals of males rather than playbacks of just acoustic signals alone. On the other hand, when it comes to the observation of complex multimodal displays in both males and females of a species, the display from both sexes might suggest that multimodal courtship signals may have evolved as a result of a bene t to intersexual communication, rather than as a result of sexual selection.

To date, the evolution of dance duets in birds has received far less attention than vocal duets. This may be in part due to the challenges of objectively quantifying dance steps, rather than lack of interest, as people in general seem to be fascinated and amused by dance, as both the popularity in reality dance shows and the social media memes of cats, dogs and other wild animals ‘dancing’ to music has shown.

However, new technologies are allowing researchers to explore nature’s dancers. As if male birds displaying seemingly elaborate dances to their own personally produced soundtrack were not enough, scientists have found that both the male and the females of one species, the blue-capped cordon-bleu (Uraeginthus cyanocephalus) engage in song and dance whilst next to each other on the same perch. But here is the catch; these birds are so fast that it takes a high-speed camera to witness their dancing!

Upon rst glance, the dance of the socially monogamous blue-capped cordon-bleu seemed to consist of bobbing up and down, while singing with a piece of nest material in their beak. However, a rhythmic beat accompanying the bobbing alerted a team of researchers that something out of the ordinary may be going on. Using, high-speed video- camera recordings the scientists revealed that there were far more foot taps going on than met the human eye. However, further analysis was needed to fully appreciate this avian dance, “Probably due to the poor time BEHAVIOUR Keeping the birds in an aviary allowed the researchers to set up cameras so they could monitor the birds’ rituals in detail. © Nao Ota. 64 - BIOSPHERE BIOSPHERE - 65 examine the variations within a single individual, as well as examining the differences between different individuals. They expected to see differences between male and females in line with the exaggerated plumage and song observed in males. They also expected to observe variation within a single individual as a bird adjusts their dance performance depending on their partner’s position and response. THE DANCE UNVEILEDHowever, contrary to predictions, no differences between males and females were observed in either the probability of dance occurring, the rate of bobbing, or the number of steps taken during a bob. In the world of birds, this is surprising seeing that females are thought to be the choosier sex. Even more surprising, is that female cordon-bleus seem to be choosy when it comes to their mates, but they do not seem to be selecting mates based off their dance performance. Yet, individual birds seemed to have their own style, with individuals varying how often he or she danced and the number of steps taken per bob; some birds are ‘break dancers’ whilst some are ‘slow dancers’.

Additionally, contrary to the human adage of ‘dance like no one is watching’, both male and female birds danced more intensely, bobbing more quickly and taking more steps per bob, when their partner was present. These results highly suggest that this dance display may function as intersexual communication, with the bobbing and steps conveying some sort of information beyond male quality. The authors suggest that the bobbing movements may bring attention to the plumage of their heads, which differs between males and females, and/or the nesting materials that they hold.

Furthermore, while singing, birds bobbed faster, but took fewer steps. This may be an adaptation to minimise interference between the sounds produced by singing versus the sounds and vibrations produced by the tapping feet. On the other hand, this may have also been a result of the constraints of dancing, singing and tapping at the same time - a physically demanding activity. THE SHOW MUST GO ONNaturalists and scientists have observed for decades that male birds have these fantastic, mind-blowing displays (just see the BBC Earth productions for amazing footage of dancing birds), and despite all these years of photographing and video-recording these splendid performances we have barely scratched the surface of just how they evolved, just how complex they are (such as individual, sex and group signatures) and how they are developed (tutors, mimicry, developmental time frame). Now, this study demonstrates that females, too, are performing complex multimodal courtship displays, which suggests that these signals may have evolved to serve in intersexual communication and social bonding. Previous studies have already hypothesised that duets may serve to signal commitment to the pair bond, and previous studies have shown links between acoustic signals and social bonding. As such, the cordon-bleu multimodal duet may lead the way towards further understanding the evolution of multimodal signals in courtship. Furthermore, non-vocal acoustic communication, What is the inherent What is the inherent What is the inherent What is the inherent bene t to these bene t to these bene t to these birds? BEHAVIOUR known scienti cally as sonation, remains a largely untapped area of research. In most species, a non- vocal acoustic signal occurs instead of, rather than in addition to, an acoustic signal. For example, during courtship ights, the Anna’s hummingbird ‘chirps’ with its tail, by means of modi ed tail feathers. Crested pigeons, Ocyphaps lophotes, have vocal courtship and territorial calls, but alarm calls are produced with modi ed wing feathers. So, it is most exciting and intriguing that the cordon-bleu appears to produce two acoustic signals at the same time.

The production of two acoustic components then begs the question whether these birds are somehow coordinating the signals, not necessarily in a harmony versus melody sort of way, but as a way to enhance the clarity or ef cacy of the signal.

“If the coordination between singing and dancing matters for females, that would be very interesting,” says Masayo, For example, when playing a goblet style drum, the drummer nominally uses one hand to play a ‘simpler’ base rhythm (also referred to as a skeleton rhythm) and the other hand to embellish the base rhythm. The base rhythm allows for a strong sense of timing to be achieved while the other hand allows elaboration, character and style to be added to the music. You can think of this second hand as the individual are, or in the case of bioacoustics studies, the individual ‘signature’, or other signatures such as group, sex or status signatures.

Both male and female blue-capped cordon-bleus sing and dance at a whole new level by incorporating two acoustic components, rhythmic feet and vocal song, to their head-bob visual display. By doing so, these birds challenge what scientists know about the evolution of multi-modal communication.

Studying these birds and other species that engage in male and female multimodal may one day further elucidate the complexity and evolution of these elaborate, mesmerising displays that continue to captivate mankind’s attention and imagination. Miya is an Assistant Professor at St.George’s University, Grenada, West Indies. She researches animal communication and social networks and how this relates to an individuals survival and tness. Ota, N., Gahr, M., & Soma, M. (2015). Tap dancing birds: the multimodal mutual courtship display of males and females in a socially monogamous songbird. Scienti c Reports, 5, 16614. © Nao Ota