Biology subjects

Aplin, L. M.

Publications and source records attributed to Aplin, L. M..

At least 19 recordsLinked to original sources

bioRxiv2025

Sex-dependent carry-over between winter associations and breeding proximity in a communally roosting parrot

Between-season carry-over in social associations is widely observed and can have important benefits for individuals, ranging from reduced conflict between neighbours to cooperative nest defence. Yet the underlying drivers of social carry-over effects remain unclear, as current research has predominantly focused on species where breeding territories are influenced by individuals non-breeding spatial distribution, making it challenging to disentangle social and spatial preferences. Sulphur-crested cockatoos (Cacatua galerita) form communal night-roosts with fission-fusion dynamics around the roost-site. During spring, breeding individuals split from the roost to occupy nearby tree hollows, but remain non-territorial, allowing us to test whether individuals exhibit a preference to breed in proximity to winter social associates. We find that male--but not female-- winter social associations are correlated with breeding location; males bred closer to their winter associates, and more socially connected males tended to breed closer to the roost location. Male cockatoos are largely philopatric to their natal roost, and exhibit long-lasting foraging associations, preferentially with kin. Our results demonstrate carry-over between these social networks and the fine-scale arrangement of breeding individuals, consistent with an active choice to retain stable, across-context social relationships.

animal behavior and cognition↗

bioRxiv2025

Social and ecological factors associated with innovation in urban sulphur-crested cockatoos (Cacatua galerita)

Why some species thrive in urban environments while others do not is a central question in behavioral ecology. Behavioral innovations has been proposed as a key mechanism facilitating this adaptation. At the individual level, innovativeness varies with cognitive and behavioral traits. However, at the population level, innovation rates can also be influenced by social and ecological factors including group size, and environmental novelty and complexity. The role of these factors are still under-explored, especially at within-city scales. To disentangle factors influencing group-level variation in innovation rates, we presented roosts of wild sulphur-crested cockatoos Cacatua galerita, with extractive-foraging tasks that required innovative problem-solving. We installed three tasks of different levels of difficulty on trees at fifteen communal roost sites across an urban matrix. We matched these with direct measures of roost-size and connectivity, and with high-resolution remote-sensing mapping to estimate variation in urbanization and environmental heterogeneity. We found that approach time was significantly associated with urbanization, with individuals in more urban sites approaching tasks more quickly, suggesting reduced neophobia with urbanization or increased familiarity with human-derived objects. In contrast, time to innovate in our study was explained by task difficulty rather than environmental and social factors. While we detected no significant effects of group size, connectivity, and environmental heterogeneity, larger sample sizes may be needed to reveal more subtle influences on innovation. Together, these results suggest that urbanization gradients can shape behavioral responses to novelty independently from problem-solving abilities. Lay SummaryCities are challenging places for wildlife, but some species, like sulphur-crested cockatoos, adapt by finding new ways to feed and solve problems. We studied how urbanization and social factors vary with cockatoos ability to innovate when presented with extractive-foraging tasks. We found that birds in more urban areas approached the tasks more quickly, suggesting reduced neophobia or increased familiarity with novel objects. This work highlights behavioral differences across urbanization gradients in human-dominated environments.

animal behavior and cognition↗

bioRxiv2025

To preen or not to preen: social predictors of allopreening in a wild parrot

Allogrooming is fundamental to social relationships in many group-living mammals. In primates, allogrooming has been the subject of decades of research, and has been shown to play an essential role in maintaining social affiliations, and often interchanged for social tolerance and support. Yet, while the equivalent behaviour of allopreening occurs in many avian species, most description has been limited to its role in pair formation and maintenance, with little known about non-pair contexts. Here we investigated the decision-making associated with allopreening in wild sulphur-crested cockatoos, conducting detailed observations of 182 allopreening events between 126 individuals while concurrently recording rank, aggressive interactions, and social networks. We found no influence of sex as predicted if allopreening was primarily about pair bonding, but instead a positive correlation between allopreening and aggression (given and received). Within interactions, individuals were influenced by social association strength and rank, with individuals preening for longer and with more turn-taking when interacting with stronger social associates, and individuals investing more in interactions initiated by higher-ranked individuals. Our results are highly suggestive that allopreening may serve a convergent function in wild parrots to primates, both in maintaining social bonds and in negotiating social tolerance.

animal behavior and cognition↗

bioRxiv2025

Temporal dynamics and policy implications in an innovation arms race

Human-modified environments offer novel resources, but their exploitation can be a source of human-wildlife conflict. Residents of Sydney have reported increasing cases of bin-opening behavior by sulphur-crested cockatoos (Cacatua galerita), with evidence this behavior is socially learned between birds. Households protected their bins, yet cockatoos have learned to defeat these defences. In response, residents increased their defence-level, setting the stage for a behavioral "arms race". Here, we investigate this arms race by combining field observations with agent-based modeling. We systematically document protections in a suburban locality over two years, revealing spatial clustering of protections indicative of social learning among residents. We find that protections have decreased since 2019, and overly-costly protection is dis-preferred. With a controlled assay, we characterize the knowledge of local cockatoos, finding differential proficiency in defeating protections. Surprisingly, we identified several cockatoos that can defeat high-efficacy protections, such as locks. Finally, we simulate interactions between two populations of learning agents representing households and cockatoos. We find that social learning accelerates adaptation in both species, while coordination reduces costs associated with defensive escalation. However, policy interventions can have unintended consequences, accelerating cockatoos skill acquisition and shifting conflict to neighboring areas. Our findings highlight the dynamic nature of human-wildlife conflict and the importance of considering behavioral feedback loops in urban wildlife management.

animal behavior and cognition↗

bioRxiv2024

Social and spatial drivers of the multitiered structure of zebra finch social networks

Social network structure plays a key role in shaping processes in animal populations. These networks often show distinct patterns in humans and other large mammals, with relationship strengths organized into different tiers. Here, we used continuous, fine-scale tracking of four large captive colonies of zebra finches (Taeniopygia guttata), revealing that zebra finches consistently have 1-2 closest contacts, 6-7 close contacts, and 22-24 strong contacts. The identities of these contacts remain stable across days, with strong contacts maintained by spatial affinity while closest and close contacts are maintained by social choice. These results suggest that zebra finches egocentric networks and social structure are made up of consistent, differentiated relationships forming a multitiered social structure. The similarities in patterns to other species suggest that fundamental principles, such as limitations in time and the ability to move through social space, could drive common structural properties in animal social networks.

animal behavior and cognition↗

bioRxiv2024

The effect of social structure on vocal flexibility in monk parakeets

The social complexity hypothesis argues that communicative complexity arises as a result of social complexity, with this occurring through mechanisms including plasticity and selection. Most research to date has focused on ultimate drivers of repertoire size, for example finding that cooperative breeding species exhibit larger repertoires. Until this date no study has focused on individual-level drivers of vocal diversity. Here, we examine social networks and vocalisations in wild colonial-nesting monk parakeets (Myiopsitta monachus). First, we recorded social networks for 337 individuals, relatedness for 100 individuals and matched these with 5599 vocalisations from 229 individuals over two years. Overall, we found that all individuals exhibited high contact-call diversity; however, individual-level diversity increased with age in 2020 and with number of nest mates in 2021. Call similarity was not predicted by relatedness, but individuals with stronger affiliative bonds had more dissimilar calls, suggesting an active process to sound unique among close associates. Finally, females had more diverse repertoires, producing relatively fewer contact calls across years and individuals living in larger groups had more diverse repertoires in 2021. Our results demonstrate a multi-faceted social influence on call content, diversity and repertoire diversity, exhibiting how fine-scale variation in social structure can influence expressed vocal complexity.

animal behavior and cognition↗

bioRxiv2024

Low-cost animal tracking using Bluetooth low energy beacons on a crowd-sourced network

O_LIAnimal tracking has opened the door to address many fundamental questions in ecology and conservation. While historically animals have been tracked as a means to understand their large-scale movements, such as migration, there is now a greater focus on using tracking to study movements over smaller scales, individual variation in movement, or how movements shape social network structure. With this shift in focus also comes different tracking needs, including the need to track larger numbers of individuals. C_LIO_LITracking studies all face some technological limitations. For example, GPS and other active tracking solutions can collect fine-scale movement data, but have a high cost per tag, limiting the number of individuals that can be followed. They also have high energy costs of data acquisition and download, limiting time periods over which data can be collected. Low-energy passive (e.g. PIT) or active (e.g. reverse GPS) tags can overcome these limitations, but instead require animals to remain within a bounded study area or to come into close proximity to detectors. C_LIO_LIHere we describe one solution that can overcome many current limitations by employing the massive global network of personal mobile phones as gateways for tracking animals using Bluetooth low energy (BLE) beacons. In areas with medium to high density of people, these simple-to-make beacons can provide regular updates of position over long time periods (battery life 1-3 years). We describe how to use off-the-shelf components to produce BLE beacons that weigh c. 5-6 g and cost < $7USD. Using field testing, we then show that beacons are capable of producing high-frequency tracking data that can be used to build home ranges or to detect spatio-temporal co-occurrences among individuals. C_LIO_LIBLE beacons are a low cost, low energy solution for studying organisms (e.g. birds, mammals, and reptiles) living and moving in urban landscapes. Their low weight and small size makes them particularly well-suited for tracking smaller species. When combined with fixed gateways, their use can also be extended to non-urban habitats. Their high accessibility is likely to make them an attractive solution for many research projects. C_LI

animal behavior and cognition↗

bioRxiv2024

Peering into the world of wild passerines with 3D-SOCS: synchronized video capture and posture estimation

O_LICollection of large behavioural data-sets on wild animals in natural habitats is vital in ecology and evolution studies. Recent progress in machine learning and computer vision, combined with inexpensive microcomputers, have unlocked a new frontier of fine-scale markerless measurements. C_LIO_LIHere, we leverage these advancements to develop a 3D Synchronized Outdoor Camera System (3D-SOCS): an inexpensive, mobile and automated method for collecting behavioural data on wild animals using synchronized video frames from Raspberry Pi controlled cameras. Accuracy tests demonstrate 3D-SOCS markerless tracking can estimate postures with a 3mm tolerance. C_LIO_LITo illustrate its research potential, we place 3D-SOCS in the field and conduct a stimulus presentation experiment. We estimate 3D postures and trajectories for multiple individuals of different bird species, and use this data to characterize the visual field configuration of wild great tits (Parus major), a model species in behavioural ecology. We find their optic axes at approximately {+/-}60{degrees} azimuth and -5{degrees} elevation. Furthermore, birds exhibit functional lateralization in their use of the right eye with conspecific stimulus, and show individual differences in lateralization. We also show that birds convex hulls predicts body weight, highlighting 3D-SOCS potential for non-invasive population monitoring. C_LIO_LI3D-SOCS is a first-of-its-kind camera system for wild research, presenting exciting potential to measure fine-scaled behaviour and morphology in wild birds. C_LI

animal behavior and cognition↗

bioRxiv2024

Immigrant birds use payoff biased social learning in spatially variable environments

Longstanding theory predicts that strategic flexibility in when and how to use social information can help individuals make adaptive decisions, especially when environments are temporally or spatially variable. A short-term increase in reliance on social information under these conditions has been experimentally shown in primates, including humans, but whether this occurs in other taxa is unknown. We asked whether migration between spatially variable environments affected social information use with a large-scale cultural diffusion experiment with wild great tits (Parus major) in captivity, a small passerine bird that can socially learn novel behaviors. We simulated an immigration event where knowledgeable birds were exchanged between groups with opposing preferences for a socially learned foraging puzzle, living in similar or different environments. We found evidence that both immigrants and residents were influenced by social information and attended to the rewards that others received. Our analysis supported the use of a payoff-biased social learning by immigrants when both resources and habitat features were spatially variable. In contrast, immigrants relied more-so on individual learning when payoffs or the environment were unchanged. In summary, our results suggest that great tits assess the payoffs others receive, and are more influenced by socially observed differences in payoffs when environmental cues differ in their new environment. Our results provide experimental support for the hypothesis that spatial variability is a strong driver for the evolution of social learning strategies.

animal behavior and cognition↗

bioRxiv2024

Long-term stability of dominance hierarchies in a wild parrot with fission-fusion dynamics

Dominance hierarchies are a common feature of stable groups, allowing animals to limit the costs of fighting over access to resources. However, while the emergence of dominance is relatively well known from species that form stable groups, less is known about whether hierarchies are maintained in societies with open group membership. One challenge for species that live in an open social environment is that they have the possibility of engaging in dominance interactions with a large number of conspecifics. To better understand how animals navigate the complexities of interacting within a large, open society, we recorded social associations and aggressive interactions in a highly social, communally roosting parrot, the sulphur-crested cockatoo (Cacatua galerita). By following 515 individuals across three neighbouring communities and recording social interactions during foraging, we show that sulphur-crested cockatoos form clear, linear hierarchies. We find males rank higher than females and that adults rank higher than juveniles. Within sex, where individuals may still have to compete with up to 100 individuals from the same age-sex class, body size did not affect dominance rank. Finally, we find that, despite highly dynamic social associations (fission-fusion dynamics) among individuals, hierarchies are stable, with dominance ranks being highly repeatable across at least three years. This study demonstrates that closed group membership is not a pre-requisites for stable dominance hierarchies to emerge.

animal behavior and cognition↗

bioRxiv2023

Social decision-making in a wild parrot relies on both individual recognition and intrinsic markers

O_LIDominance hierarchies are generally thought to form over time via memory of repeated interactions. However, dominance hierarchies are also occasionally reported in species with fission-fusion social dynamics, where individuals may encounter large numbers of individuals, leading to incomplete social information. It it has been alternatively proposed that the complex decision-making required in these circumstances may lead to increased selection for social cognition and memory, or to the evolution of mixed strategies that rely on memory for interaction with familiars and status signals for strangers. C_LIO_LIHere, test these competing hypotheses by recording social associations and aggressive interactions in a highly social, large-brained parrot, the sulphur-crested cockatoo ( Cacatua galerita). We followed 411 individuals across three neighbouring roost sites, where individuals exhibit stable dominance hierarchies within roosts, alongside a high degree of fission-fusion dynamics within roosts and regular between-roost movements. C_LIO_LIWe found evidence that sulphur-crested cockatoos use a two-fold social strategy when initiating or reacting to an aggression. For familiar individuals, aggressions were initiated or escalated based on rank difference. When facing less familiar individuals, decisions to interact -- or escalate -- were based on the relative weight, with interactions directed towards, and more likely to escalate between, individuals of similar weight. C_LIO_LIOur results suggest that social knowledge remains an important determinant of aggressive interactions in highly fission-fusion systems, but that individuals can dynamically incorporate other potential cues of competitive ability when knowledge is lacking. C_LI

animal behavior and cognition↗

bioRxiv2023

Wild sulphur-crested cockatoos match human activity rhythms to access food in the urban environment

AO_SCPLOWBSTRACTC_SCPLOWUrban areas are growing rapidly across the globe, and wild species are occupying this new environment. Despite offering potential resources, disparities in the urban matrix can lead to specific challenges, with pathways and resources fragmented in space and time. Urban-dwelling species would therefore benefit from learning when and where to exploit human derived food. Here, we investigate whether birds synchronize the exploitation of the most urbanized areas to match food-provisioning patterns, using the example of the popular hand-feeding of sulphur-crested cockatoos (Cacatua galerita) in Sydney, Australia. We monitored the provisioning behaviour of people via a large-scale citizen science program, and tested for synchrony with the spatial behaviour of eight birds equipped with GPS loggers. Our data show that sulphur-crested cockatoos exploited the urban environment, relying on the green areas of the city; importantly, they also visited buildings within more urbanized areas. Sulphur-crested cockatoos used urban space with specific time patterns particularly matching human recreational feeding routines, suggestive of time-place learning. We show that urban environments provide daily temporal foraging resources for which species adjust behaviorally. Thus, our data support the general claim that retaining green spaces in cities is essential to sustainable urban planning, and key to allow species to exploit the urban environment, particularly in areas of high human density. This study builds on the literature investigating human-animal interactions, expanding our understanding of animals exploitation of human behavior. Further research should include the impact of such interactions on urban wildlifes fitness according to their cognitive and behavioral traits.

animal behavior and cognition↗

bioRxiv2023

callsync: an R package for alignment and analysis of multi-microphone animal recordings

O_LITo better understand how vocalisations are used during interactions of multiple individuals, studies are increasingly deploying on-board devices with a microphone on each animal. The resulting recordings are extremely challenging to analyse, since microphone clocks drift non-linearly and record the vocalisations of non-focal individuals as well as noise. C_LIO_LIHere we address this issue with callsync, an R package designed to align recordings, detect and assign vocalisations to the caller, trace the fundamental frequency, filter out noise and perform basic analysis on the resulting clips. C_LIO_LIWe present a case study where the pipeline is used on a dataset of six captive cockatiels (Nymphicus hollandicus) wearing backpack microphones. Recordings initially had drift of [~]2 minutes, but were aligned to within [~]2 seconds with our package. Using callsync, we detected and assigned 2101 calls across three multi-hour recording sessions. Two had loud beep markers in the background designed to help the manual alignment process. One contained no obvious markers, in order to demonstrate that markers were not necessary to obtain optimal alignment. We then used a function that traces the fundamental frequency and applied spectrographic cross correlation to show a possible analytical pipeline where vocal similarity is visually assessed. C_LIO_LIThe callsync package can be used to go from raw recordings to a clean dataset of features. The package is designed to be modular and allows users to replace functions as they wish. We also discuss the challenges that might be faced in each step and how the available literature can provide alternatives for each step. C_LI

ecology↗

bioRxiv2023

Evidence for vocal signatures and voice-prints in a wild parrot

In humans, identity is partly encoded in a voice-print that is carried across multiple vocalisations. Other species also signal vocal identity in calls, such as shown in the contact call of parrots. However, it remains unclear to what extent other call types in parrots are individually distinct, and whether there is an analogous voice-print across calls. Here we test if an individual signature is present in other call types, how stable this signature is, and if parrots exhibit voice-prints across call types. We recorded 5599 vocalisations from 229 individually-marked monk parakeets (Myiopsitta monachus) over a two year period in Barcelona, Spain. We examined five distinct call types, finding evidence for an individual signature in three. We further show that in the contact call, while birds are individually distinct, the calls are more variable than previously assumed, changing over short time scales (seconds to minutes). Finally, we provide evidence for voice-prints across multiple call types, with a discriminant function being able to predict caller identity across call types. This suggests that monk parakeets may be able to use vocal cues to recognise conspecifics, even across vocalisation types and without necessarily needing active vocal signatures of identity.

animal behavior and cognition↗

bioRxiv2022

Multi-level analysis of monk parakeet vocalisations shows emergent dialects between cities in the European invasive range

Geographic differences in vocalisations provide strong evidence for animal culture, with patterns likely arising from generations of social learning and transmission. The current knowledge on the evolution of vocal variation has predominantly focused on fixed repertoire, territorial song in passerine birds. The study of vocal communication in open-ended learners and in contexts where vocalisations serve other functions is therefore necessary for a more comprehensive understanding of vocal dialect evolution. Parrots are open-ended vocal production learners that use vocalisations for social contact and coordination. Geographic variation in parrot vocalisations typically take the form of either distinct regional variations known as dialects or graded variation based on geographic distance known as clinal variation. In this study, we recorded monk parakeets (Myiopsitta monachus) across multiple spatial scales (i.e. parks and cities) in their European invasive range. We then compared calls using a multi-level Bayesian model and sensitivity analysis, with this novel approach allowing us to explicitly compare vocalisations at multiple spatial scales. We found support for founder effects and/or cultural drift at the city level, consistent with passive cultural processes leading to large scale dialect differences. We did not find a strong signal for dialect or clinal differences between parks within cities, suggesting that birds did not actively converge on a group level signal, as expected under the group membership hypothesis. We demonstrate the robustness of our findings and offer an explanation that unifies the results of prior monk parakeet vocalisation studies.

ecology↗

bioRxiv2022

Optimal population turnover regimes for cultural evolution depend on network size, density and behavioral transmissibility

A change to a populations social network is a change to the substrate of cultural transmission, affecting behavioral diversity and adaptive cultural evolution. While features of network structure such as population size and density have been well studied, less is understood about the influence of social processes such as population turnover-- or the repeated replacement of individuals. Experimental data has led to the hypothesis that naive learners can drive cultural evolution by being better samplers, although this hypothesis has only been expressed verbally. We conduct a formal exploration of this hypothesis using a generative model that concurrently simulates its two key ingredients: social transmission and reinforcement learning. We explore how variation in turnover influences changes in the distributions of cultural behaviors over long and short time-scales. We simulate competition between a high and low reward behavior, while varying turnover magnitude and tempo. We find optimal turnover regimes that amplify the production of higher reward behaviors. We also find that these optimal regimes result in a new population composition, where fewer agents which know both behaviors, and more agents know only the high reward behavior. These two effects depend on network size, density, behavioral transmissibility, and characteristics of the learners. Our model provides formal theoretical support for, and predictions about, the hypothesis that naive learners can shape cultural change through their enhanced sampling ability, identified by previous experimental studies. By moving from experimental data to theory, we illuminate an under-discussed generative process arising from an interaction between social dynamics and learning that can lead to changes in cultural behavior.

animal behavior and cognition↗

bioRxiv2022

Multi-network analysis reveals context-dependent kin relationships in wild sulphur-crested cockatoos, Cacatua galerita

O_LIA preference to associate with kin facilitates inclusive fitness benefits, and increased tolerance or cooperation between kin may be an added benefit of group living. Many species exhibit preferred associations with kin, however it is often hard to disentangle active preferences from passive overlap, for example caused by limited dispersal or inheritance of social position. C_LIO_LIMany parrots exhibit social systems consisting of pair-bonded individuals foraging in variably sized fission-fusion flocks within larger communal roosts of hundreds of individuals. Previous work has shown that, despite these fission-fusion dynamics, individuals can exhibit long-term preferred foraging associations outside their pair-bonds. Yet the underlying drivers of these social preferences remains largely unknown. C_LIO_LIIn this study, we use a network approach to examine the influence of kinship on social associations and interactions in wild, communally roosting sulphur-crested cockatoos, Cacatua galerita. We recorded roost co-membership, social associations and interactions in 561 individually marked birds across three neighbouring roosts. We then collected genetic samples from 205 cockatoos, and conducted a relationship analysis to construct a kinship network. Finally, we tested correlations between kinship and four social networks: association, affiliative, low-intensity aggression, and high-intensity aggression. C_LIO_LIOur result showed that while roosting groups were clearly defined, they showed little genetic differentiation or kin structuring. Between roost movement was high, with juveniles, especially females, repeatedly moving between roosts. Both within roosting communities, and when visiting different roosts, individuals preferentially associated with kin. Supporting this, individuals were also more likely to allopreen kin. However, contrary to expectation, individuals preferred to direct aggression towards kin, with this effect only observed when individuals shared roost membership. C_LIO_LIBy measuring social networks within and between large roosting groups, we could remove potential effects of passive spatial overlap on kin structuring. Our study reveals that sulphur-crested cockatoos actively prefer to associate with kin, both within and between roosting groups. By examining this across different interaction types, we further demonstrate that sulphur-crested cockatoos exhibit behavioural and context-dependent interaction rules towards kin. Our results help reveal the drivers of social association in this species, while adding to the evidence for social complexity in parrots. C_LI

animal behavior and cognition↗

bioRxiv2021

Cultural diffusion dynamics depend on behavioural production rules

Culture is an outcome of both the acquisition of knowledge about behaviour through social transmission, and its subsequent production by individuals. Acquisition and production are often discussed interchangeably or modeled separately, yet to date, no study has accounted for both processes and explored their interaction. We present a generative model that integrates the two to explore how variation in production rules might shape cultural diffusion dynamics. Agents make behavioural choices that change as they learn from their productions. Their repertoires also change over time, and the social transmission of behaviours depends on their frequency. We diffuse a novel behaviour through social networks across a large parameter space to demonstrate how individual-level behavioural production rules influence population-level diffusion dynamics. We then investigate how linking transmission and production might affect the performance of two commonly used inferential models for social learning; Network-based Diffusion Analysis, and Experienced Weighted Attraction models. Clarifying the distinction between acquisition and production yields predictions for how production influences diffusion that are generalisable across species, and has consequences for how inferential methods are applied to empirical data. Our model illuminates the differences between social learning and social influence, demonstrates the overlooked role of reinforcement learning in cultural diffusions, and allows for clearer discussions about social learning strategies.

animal behavior and cognition↗