Biology subjects

Webb, W. H.

Publications and source records attributed to Webb, W. H..

3 recordsLinked to original sources

bioRxiv2025

Vocally mediated coordination during a cooperative task in parrots

Studying vocal coordination in a cooperative setting provides insights into how animals process social information, coordinate their actions, and make decisions in complex social settings. It can also reveal how animals use vocal signals to navigate complex social interactions that might not be apparent in solitary or non-cooperative contexts. To our knowledge, experimental evidence for intentional vocal communication in controlled experiments has been demonstrated only in dolphins. Here, we investigate whether peach-fronted conures (Eupsittula aurea) can use vocal communication to coordinate behaviour in a cooperative task. We chose parrots due to their complex social systems, their vocal learning and mimicry skills, and their advanced cognitive abilities. We tested four individuals pairwise in all combinations in the loose string paradigm, which requires synchronization of the two individuals to retrieve a food reward by simultaneously pulling a string. To verify that the parrots used vocal communication to solve the task, we tested them first under three control conditions where visual information and simple behaviour sufficed to solve the tasks. We then compared their vocal behaviour in the control conditions with their vocal behaviour in a task without visual information. During performance of the latter task, the birds demonstrated significantly higher call rates and variability and specific associations between call types and trial outcome compared to the control conditions. After the performance of the task, the birds used vocal convergence more often after failed trials, potentially as a reconciliation mechanism. Our results indicate that peach-fronted conures can use vocalizations to coordinate the solving of a cooperative task, and that vocal convergence may serve as a bonding mechanism following unsuccessful cooperative efforts.

animal behavior and cognition↗

bioRxiv2021

Sexual and temporal variation in New Zealand bellbird song repertoires

How song repertoires vary within species and change over time is well studied in male songbirds. However, variation in female song repertoires remains largely unstudied despite female song being much more common and complex than once assumed. We investigated the song syllable repertoire of the New Zealand bellbird (Anthornis melanura), a species where both sexes have complex but sexually dimorphic song. We compared songs at individual and population levels to investigate sex and temporal variation of syllable repertoires. We detected 96 syllable types in the population over four years, of which 58% were unique to males, 32% unique to females and 9% were shared between the sexes. The population syllable repertoire of both sexes changed substantially across years with similar turnover rates (Jaccards similarity coefficients; female 52.9-69.0%; male 58.6-73.7%). Furthermore, many syllable types, unique to each sex, varied in prevalence within the population across years. The syllable repertoire sizes of individuals were higher for males than females (13-32, n = 7 and 6-16, n = 8, respectively). Although these sample sizes were low, the temporal variation in syllable prevalence and turnover for individuals were similar to patterns at the population level. Overall, male and female bellbirds exhibited similarities in temporal patterns of yearly repertoire composition, with rapid changes in syllable prevalence, but females had fewer syllable types than males. We suggest that these similarities and differences are consistent with male and female song repertoires being driven by similar but not identical selection pressures.

animal behavior and cognition↗

bioRxiv2021

Sexually distinct song cultures in a songbird metapopulation

Songbirds learn their songs culturally, through imitating tutors. The vocal culture of a songbird population changes as new song units (syllables) are introduced through immigration, copying errors, and innovation, while other syllables fall out of use. This leads to a diversification of the syllable pool across the species, much like the diversification and spatial patterns of human language. Vocal cultures have been well studied in male songbirds but have been largely overlooked in females. In particular, few studies compare spatial variation of male and female song cultures. Here we undertake one of the first comparisons of male and female song culture in birds, analysing song data from a metapopulation of New Zealand bellbirds Anthornis melanura, spanning an archipelago of six islands. Having classified 20,700 syllables, we compare population syllable repertoire sizes and overlap between sites and sexes. We show that males and females--both with complex songs--have distinct song cultures, sharing only 6-26% of syllable types within each site. Furthermore, male and female syllable types can be statistically discriminated based on acoustic properties. Despite diverse syllable repertoires within sites, few syllable types were shared between sites (both sexes had highly distinct site-specific dialects). For the few types shared between sites, sharing decreased with distance only for males. Overall, there was no significant difference between sexes in degree of site-site repertoire overlap. These results suggest different cultural processes at play for the two sexes, underlining the inadequacy of male-centric song research and calling for comparisons of male and female song cultures in many more species.

animal behavior and cognition↗