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Display courts are fundamental to the sexual displays of many species of bird; however, the ecology of display courts is poorly understood, representing an important gap in our understanding of the function and evolution of complex animal displays. Here, we describe the biophysical attributes (‘ecology’) of the display courts of male Albert’s Lyrebirds, a ground-dwelling rainforest species that performs a spectacular song and dance display on set courts, known as ‘display platforms’, that are composed of vines or fallen branches. Males rhythmically move these vegetative structures while singing, forming a unique ‘stage shaking’ component of their sexual display. We investigated whether display platforms differed from random locations within a male’s territory in terms of the number of vines or other vegetative structures, area of ground clearing, vegetation density, and canopy cover measurements. We primarily found that platforms had a larger number of vines or other vegetative structures. Platforms also tended to be in areas with more canopy openings. We suggest that platform features amplify the movement of the dancing male, and that male Albert’s Lyrebirds choose platforms in locations that increase their conspicuousness to female receivers. [ABSTRACT FROM AUTHOR]

Where dramatic sexual displays are involved in attracting a mate, individuals can enhance their performances by manipulating their physical environment. Typically, individuals alter their environment either in preparation for a performance by creating a "stage" or during the display itself by using discrete objects as "props." We examined an unusual case of performative manipulation of an entire stage by male Albert's lyrebirds (Menura alberti) during their complex song and dance displays. We found that males from throughout the species' range shake the entangled forest vegetation of their display platforms, creating a highly conspicuous and stereotypical movement external to their bodies. This "stage shaking" is performed in two different rhythms, with the second rhythm an isochronous beat that matches the beat of the coinciding vocalizations. Our results provide evidence that stage shaking is an integral, and thus likely functional, component of male Albert's lyrebird sexual displays and so highlight an intriguing but poorly understood facet of complex communication. [ABSTRACT FROM AUTHOR]

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Most studies of acoustic communication focus on short units of vocalization such as songs, yet these units are often hierarchically organized into higher-order sequences and, outside human language, little is known about the drivers of sequence structure. Here, we investigate the organization, transmission and function of vocal sequences sung by male Albert's lyrebirds ( Menura alberti ), a species renowned for vocal imitations of other species. We quantified the organization of mimetic units into sequences, and examined the extent to which these sequences are repeated within and between individuals and shared among populations. We found that individual males organized their mimetic units into stereotyped sequences. Sequence structures were shared within and to a lesser extent among populations, implying that sequences were socially transmitted. Across the entire species range, mimetic units were sung with immediate variety and a high acoustic contrast between consecutive units, suggesting that sequence structure is a means to enhance receiver perceptions of repertoire complexity. Our results provide evidence that higher-order sequences of vocalizations can be socially transmitted, and that the order of vocal units can be functionally significant. We conclude that, to fully understand vocal behaviours, we must study both the individual vocal units and their higher-order temporal organization.