A unique non-human model for the evolution of musical tool use: drumming by the palm cockatoo

A project undertaken at the Fenner School of Environment and Society, Australian National University, and supervised by Robert Heinsohn and Naomi Langmore


While there is growing evidence of a valid and useful analogy between human song and the song of whales, birds and seals, there have been no comparable studies of the production of instrumental music by non-human species. This reflects a virtual absence of suites of behaviour in other species that might be comparable to musical instrument use in humans. However, one species has been identified as a likely candidate, the palm cockatoo Probosciger aterrimus, which as far as we know, is the only non-human species that manufactures and uses a ‘sound tool’. Palm cockatoos make a ‘drumstick’ by breaking off a living branch, stripping off the foliage and trimming it to the appropriate length. They then grasp the drumstick in their foot and beat it against a hollow trunk making a sound that is audible at over 100 m. With the expert field assistance of Christina Zdenek we recorded 131 sequences of palm cockatoo drumming and collected over 40 drum sticks for analysis of the tool making process.

In the first of our papers from this study we explored whether palm cockatoo drumming is fully analogous to human instrumental music. The set of capacities that allows humans to produce and perceive music appears to be deeply rooted in human biology, but an understanding of its evolutionary origins requires cross-taxa comparisons. We showed that drumming by palm cockatoos shares the key rudiments of human instrumental music, including manufacture of a sound tool, performance in a consistent context, regular (rhythmic) beat production, repeated components, and individual styles. Over all 131 drumming sequences produced by 18 males, the beats occurred at non-random, regular intervals, with autocorrelation analyses of the longest drumming sequences demonstrating that they were highly regular and predictable like human music. Further, males exhibited individual drumming styles in similar fashion to human drummers, with some producing faster beats, and others introducing a signature flourish at the beginning or end. These discoveries provide a rare comparative perspective on the evolution of rhythmicity and instrumental music in our own species.

Reference:

Robert Heinsohn, Christina N. Zdenek, Ross B. Cunningham, John A. Endler, Naomi E. Langmore (2017). Tool-assisted rhythmic drumming in palm cockatoos shares key elements of human instrumental music. Science Advances 3: e160239


 Video:

https://www.youtube.com/watch?v=fyX8DuBKPZc

https://www.youtube.com/watch?v=G1VlezTRVnI

Sample press coverage:

https://www.nytimes.com/2017/06/28/science/drumming-palm-cockatoos.html

https://www.facebook.com/ajplusenglish/videos/1011674422307398/

 



Figure 1. A male palm cockatoo (right) strikes the rim of his nest hollow with a “drumstick” as he displays to a female. (Photo: C.Zdenek)