![]() Autocorrelation analyses of the longest drumming sequences further showed that they were highly regular and predictable like human music. Over 131 drumming sequences produced by 18 males, the beats occurred at nonrandom, regular intervals, yet individual males differed significantly in the shape parameters describing the distribution of their beat patterns, indicating individual drumming styles. We show that drumming by palm cockatoos (Probosciger aterrimus) shares the key rudiments of human instrumental music, including manufacture of a sound tool, performance in a consistent context, regular beat production, repeated components, and individual styles. 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. This is also a step towards assessing links between behavioural variation and population connectivity, which is important information for determining the conservation status of palm cockatoos.Īll human societies have music with a rhythmic " beat, " typically produced with percussive instruments such as drums. Such variety in vocal traits presents a rare opportunity to investigate the evolutionary forces creating behavioural diversity in wild parrots. This may have resulted from their long-term isolation in rainforest habitat refugia. We found that palm cockatoos from the east coast (Iron Range National Park) possess unique contact calls and have fewer call types in common with other locations. ![]() Here, we quantify the geographic structural variation of contact calls within and between six major populations of palm cockatoos in Australia, as well as the extent to which frequently given call types are shared. Most calls are made during their unique display ritual, which also includes a variety of postures, gestures and the use of a manufactured sound tool. The Australian population of palm cockatoos (Probosciger aterrimus aterrimus) from Cape York Peninsula in far north Queensland has an unusually large vocal repertoire for a parrot. Vocal dialects have been well studied in songbirds, but there have been fewer examples from parrots. ![]() We discuss the applicability of these results for future studies of palm cockatoos and other parrot species. However, based on a limited sample sizes of five putative individuals between years, our data suggest that individual call structure, as quantified by call parameters, was not stable between years. For three different call types, individual identification accuracy among males and females ranged from 69 to 95%. 148 out of 183 calls were assigned to the correct individual) on the basis of multiple temporal, energy (amplitude) and frequency measurements on the spectrogram. Using Discriminant Function Analysis, overall identification accuracy among 12 putative individuals for all call types was 81% (i.e. Here, we investigated whether three different palm cockatoo call types are sufficiently individually distinctive to function as a non-invasive “marker” for identifying individuals over time. Palm cockatoos (Probosciger aterrimus) are a large, poorly understood species of parrot which are likely in severe decline within the eastern part – and possibly the western part – of their range on Cape York Peninsula, Australia. However, some species, including large parrots, are notoriously difficult to catch and mark for individual identification. The ability to identify individuals within a population is often essential for a detailed understanding of the ecology and conservation of a species.
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