Biology subjects

Troisi, C. A.

Publications and source records attributed to Troisi, C. A..

9 recordsLinked to original sources

bioRxiv2025

Social connections, group size and fine-scale manipulations of social stability shape learning, scrounging and foraging rate in wild great tits

The social environment provides both opportunities and challenges for foragers. How multiple components of sociality and foraging interact simultaneously is poorly understood, while experimental manipulation of sociality within wild foraging groups is rare. We tested whether production learning, scrounging, and foraging rate are associated with individual social network metrics and manipulated social stability in mixed species flocks of wild birds. First, individuals were randomly allowed access to, and learned to forage primarily from, one of five feeders. Thereafter, we performed two reversals, manipulating social connections by either assigning birds to a new feeder along with all others assigned to their previous feeder (stable treatment) or reassigning each bird individually (unstable treatment). Most of the effects observed were context dependent but in general we found that: i) Learning was slower in the stable treatment, for individuals with higher weighted degree, and in smaller flocks; ii) Scrounging was higher in the stable treatment, increased with weighted degree, but decreased with flock size; and iii) Foraging rate was predicted only by weighted degree. Our findings demonstrate the complex and dynamic nature of the relationship between sociality and foraging and suggest that selection for group living is more nuanced than usually recognized.

animal behavior and cognition↗

bioRxiv2024

To Peck or Not To Peck: The influence of early-life social environment on response inhibition and impulsive aggression in Japanese quails

Deficits in response inhibition (i.e., the ability to suppress inappropriate responses) may contribute to increased impulsive aggression (i.e., unplanned behaviors that harm others). Since early-life environment might influence the development of response inhibition, it could also indirectly affect impulsive aggression. However, this relationship has rarely been directly examined. Here, we investigated whether response inhibition is associated with impulsive aggression and whether this relationship explains the effects of early-life social environments on impulsive aggression in juvenile Japanese quails (Coturnix japonica). Quails (n = 120) were raised in two social conditions: Small groups of five birds or Large groups of 15 birds. Response inhibition was assessed using the Barrier and Cylinder tasks, while impulsive aggression was measured in two contexts - within a group of five familiar individuals and in a dyad with an unfamiliar individual. We found that some aspects of response inhibition were related to impulsive aggression. Furthermore, quails reared in small groups showed significantly poorer response inhibition than those reared in large groups. Yet, impulsive aggression did not significantly differ between the two conditions. These findings suggest that, while impulsive aggression is partly related to response inhibition, other factors mitigate the effects of early social environments on its expression.

animal behavior and cognition↗

bioRxiv2024

Beyond a unitary construct: Dissecting stopping behaviour in two bird species

The ability to stop behaviour is essential for adapting to changes in the environment, a principle that holds true across various species. While traditionally considered a unitary psychological construct, recent studies indicate that this ability is multifaceted. Our research evaluates this multifaceted nature using three tasks that measure stopping in different contexts in two related gull species: herring gulls (Larus argentatus) and lesser black-backed gulls (L. fuscus). These species were selected for their distinct migration and foraging strategies, offering a unique lens through which to examine behavioural adaptations. Across tasks and species, we conceptualised stopping as a race between a go and a stop runner, and predicted correlations based on the type of stop stimulus, the relative timing of the go and the stop stimuli, and the type of action that needed to be stopped. We found correlations between measures of going across tasks, but there was less consistency in measures of stopping. Furthermore, we observed significant differences in going and stopping behaviours that were specific to each species, which may be linked to their migration and foraging strategies. These findings highlight the importance of considering the multifaceted nature of stopping in evolutionary and behavioural studies.

animal behavior and cognition↗

bioRxiv2023

Unravelling effects of fine-scale changes within wild-bird flocks on sociality

O_LISocial structure and individual sociality impact a wide variety of behavioural and ecological processes. Although it is well known that changes in the physical and social environment shape sociality, how perturbations govern sociality at a fine spatial scale remains poorly understood. By applying automated experimental treatments to RFID-tracked wild great tits (Parus major) in a field experiment, we examined how individual social network metrics changed when food resources and social stability were experimentally manipulated at the within-group spatial scale. C_LIO_LIFirst, we examined how individual sociality responds when food resources changed from a dispersed distribution (50m apart) to a clustered distribution (1m apart). Second, we tested how sociality changed when individuals were restricted to feeding in a manner that mimics assortative behaviour within flocks. Third, we tested the effects of experimentally manipulating the stability of these social groupings. Finally, we returned the feeders to the original dispersed distribution to test whether effects carried over. C_LIO_LIRepeatability analyses showed consistent differences among individuals in their social phenotypes across the various manipulations; dyadic association preferences also showed consistency. Nevertheless, average flock size and social centrality measures increased after the food was clustered. Some of these metrics changed further when birds were then forced to feed from only one of the five clustered feeders. There was some support for group stability at individual feeders also impacting individual social network metrics: increase in flock size was more pronounced in the stable than the unstable group. Most of the differences in sociality were maintained when the food distribution returned to the dispersed pattern, and this was caused primarily by the change in resource distribution rather than the social manipulation. C_LIO_LIOur results show that perturbations in the access to resources and social group stability can change sociality at a surprisingly fine spatial scale. These small-scale changes could arise through a variety of mechanisms, including assortative positioning within groups due to, for instance, similarity among individuals in their preferences for different resource patches. Our results suggest that small-scale effects could lead to social processes at larger scales and yet are typically overlooked in social groups. C_LI

animal behavior and cognition↗

bioRxiv2023

Nest traits for the world's birds

MotivationA well-constructed nest is a key element of successful reproduction in most species of birds, and nest-building strategies vary widely across the class. Macroecological and macroevolutionary studies tend to group nest design into a small number of discrete categories, often based on taxonomic inference. In reality, however, many species display considerable intraspecific variation in their nest-building behaviour, and broad-level categories may include many functionally distinct nest types. To address this confusion in the literature and facilitate future studies of broad-scale variation in avian parental care, we here introduce a detailed, global comparative database of nest building in birds, together with preliminary correlations between these traits and species-level environmental variables. Main types of variable containedWe present species-level data for nest structure, location, height, material composition, sex of builder, building time, and nest dimensions. Spatial location and grainGlobal. Maps are presented at the 1{degrees}x1{degrees} level. Time period and grainIncluded species are generally extant, although we present some data for recently extinct taxa. The data was collected 2017-2021 and was drawn from secondary sources published 1992-2021. Major taxa and level of measurementPartial or complete trait data is presented for 8,601 species of birds, representing 36 of 36 orders and 239 of 243 families. Software formatData have been uploaded as Supplementary Material in .xlsx format and are separated by species and source for all traits (S1) as well as summarised at the species level for structure and location variables (S2).

evolutionary biology↗

bioRxiv2023

Individual vocal recognition in the black-headed spider monkey (Ateles fusciceps)

Individual vocal recognition - the ability to discriminate between individuals based on sound - is thought to be particularly useful for social species that regularly lose visual contact between group members. For instance, individuals living in a fission-fusion group that feed on patchily distributed food in a complex physical environment (e.g., dense forest) are likely to depend heavily on vocalisation to identify individuals that are good at finding food. Spider monkeys (Ateles spp.) live in such environments and have distinctive individual contact calls (whinnies). We used a habituation-dishabituation playback-paradigm to investigate whether black-headed spider monkeys (A. fusciceps) are able to discriminate between female individuals in their group. We found that a group of captive spider monkeys was able to discriminate between individuals using those contact calls. Although many primate species have been found to have individual characteristics in their calls, this is one of the few direct experimental evidence of vocal recognition using a habituation-dishabituation paradigm.

animal behavior and cognition↗

bioRxiv2020

Inhibitory control, personality, and manipulated ecological conditions influence foraging plasticity in the great tit

O_LIOrganisms are consistently under selection to respond effectively to a diversity of, sometimes rapid, changes in their environment. Behavioural plasticity can allow individuals to do so instantaneously, but why individuals vary in this respect is poorly understood. Although personality and cognitive traits are often hypothesised to influence plasticity, the effects reported are highly inconsistent, which we hypothesise is because ecological context is usually not considered. C_LIO_LIHere we explore the roles of individual cognitive and personality variation - assayed using standard tasks for inhibitory control, a measure of self-control, and reactive-proactive personality axis (RPPA), respectively - in driving foraging plasticity, and asked how these effects varied across two experimentally manipulated ecological contexts: food value and predation risk. C_LIO_LIAfter great tits (Parus major) had initially been trained to retrieve high value food hidden in sand, they were then simultaneously offered the hidden food and an alternative food choice on the surface, that was either high or low value. Their choices were further examined under high and low perceived predation risk treatments. Individuals choices were classified in terms of whether they continued to forage on the hidden but familiar food source, or instead switched to the new visible food source. We defined the latter option as the plastic response. C_LIO_LIOur assays captured consistent differences among individuals in foraging behaviour. Both inhibitory control and exploration influenced whether birds switched from the familiar but hidden food source to the new alternative visible food on the surface. These effects depended on the relative value of the food items available and on the perceived level of predation risk, but also on the time scale over which the response was measured. C_LIO_LIOur results demonstrate how an executive cognitive function and one specific personality axis can simultaneously influence plasticity in a key functional behaviour. That their effects on foraging were primarily observed as interactions with food value or predation risk treatments also suggest that the population level consequences of behavioural mechanisms, such as these, may only be revealed across key ecological conditions or gradients. C_LI

animal behavior and cognition↗

bioRxiv2020

No evidence for cross-contextual consistency in spatial learning and behavioural flexibility in a passerine

Although the evolution of cognitive differences among species has long been of interest in ecology, whether natural selection acts on cognitive processes within populations has only begun to receive similar attention. One of the key challenges is to understand how consistently cognitive traits within any one domain are expressed over time and across different contexts, as this has direct implications for the way in which selection might act on this variation. Animal studies typically measure a cognitive domain using only one task in one context, and assume that this captures the likely expression of that domain in different contexts. This deficit is not surprising because, from an ecologists perspective, cognitive tasks are notoriously laborious to employ, and for design reasons most tasks can only be deployed in a specific context. Thus our knowledge of whether individual differences in cognitive abilities are consistent across contexts is limited. Using a wild population of great tits (Parus major) we characterised consistency of two cognitive abilities, each in two different contexts: 1) spatial learning at two different spatial scales, and 2) behavioural flexibility as both performance in a detour reaching task and reversal learning in a spatial task. We found no evidence of a correlation between the two spatial learning speeds, or between the two measures of behavioural flexibility. This suggests that cognitive performance is highly plastic and sensitive to differences across tasks, or that variants of these well-known tasks may tap into different combinations of both cognitive and non-cognitive mechanisms, or that they simply do not adequately measure each putative cognitive domain. Our results highlight the challenges of developing standardised cognitive assays to explain natural behaviour and to understand the selective consequences of that variation.

animal behavior and cognition↗

bioRxiv2019

Ecology, phylogeny, and the evolution of developmental duration in birds

The duration of the developmental period represents a fundamental axis of life history variation in animals, yet broad insights regarding the drivers of this diversity are currently lacking. Here using embryological data combined with information on incubation and fledging periods for 3096 species, we test key mechanistic and adaptive explanations for the evolutionary diversification of developmental durations in birds. First, using data on embryonic development for 20 model species, we show that developmental phases associated primarily with growth are longer and more variable than earlier phases, consistent with a role for allometric constraint in determining the duration of development. Second, using phylogenetic comparative methods, we find that avian developmental durations retain a strong imprint of deep evolutionary history, and that after accounting for these effects, body size differences among species explain less variation (5-22%) in developmental period lengths than previously thought. Finally, by collecting data for a suite of potential explanatory variables, our analyses reveal broad-scale ecological correlates of developmental durations, including variables associated with the relative safety of the developmental environment (e.g. nest height, insularity) and pressures of breeding phenology (e.g. migration). Overall, our results reveal that the combined effects of species body size, ecology, and phylogenetic history can account for 62-93% of the variation in developmental durations across birds, providing broad-scale quantitative insight into the relative importance of mechanistic constraints, adaptive evolution and evolutionary constraints in shaping the diversification of this key life-history trait.

evolutionary biology↗