Publications by year
In Press
Jolles JW, Boogert NJ, Sridhar VH, Couzin ID, Manica A (In Press). Consistent individual differences drive collective behaviour and group functioning of schooling fish. Current Biology
Evans JC, Hodgson DJ, Boogert NJ, Silk MJ (In Press). Group size and modularity interact to shape the spread of infection and information through animal societies.
Abstract:
Group size and modularity interact to shape the spread of infection and information through animal societies
AbstractSocial interactions between animals can provide many benefits, including the ability to gain useful environmental information through social learning. However, these social contacts can also facilitate the transmission of infectious diseases through a population. Animals engaging in social interactions must therefore face a trade-off between the potential informational benefits and the risk of acquiring disease. In order to understand how this trade-off can influence animal sociality, it is necessary to quantify the effects of different social structures on individuals’ likelihood of acquiring information versus infection Theoretical models have suggested that modular social networks, associated with the formation of groups or sub-groups, can slow spread of infection by trapping it within particular groups. However these social structures will not necessarily impact the spread of information in the same way if its transmission is considered as a “complex contagion”, e.g. through individuals copying the majority (conformist learning). Here we use simulation models to demonstrate that modular networks can promote the spread of information relative to the spread of infection, but only when the network is fragmented and group sizes are small. We show that the difference in transmission between information and disease is maximised for more well-connected social networks when the likelihood of transmission is intermediate. Our results have important implications for understanding the selective pressures operating on the social structure of animal societies, revealing that highly fragmented networks such as those formed in fission-fusion social groups and multilevel societies can be effective in modulating the infection-information trade-off for individuals within them.Significance statementRisk of infection is commonly regarded as one of the costs of animal social behaviours, while the potential for acquiring useful information is seen as a benefit. Balancing this risk of infection with the potential to gain useful information is one of the key trade-offs facing animals that engage in social interactions. In order to better understand this trade-off, it is necessary to quantify how different social structures can promote access to useful information while minimising risk of infection. We used simulations of disease and information spread to examine how group sizes and social network fragmentation influences both these transmission processes. Our models find that more subdivided networks slow the spread of disease far more than infection, but only group sizes are small. Our results demonstrate that showing that fragmented social structures can be more effective in balancing the infection-information trade-off for individuals within them.
Abstract.
Goumas M, Kelley L, Boogert N (In Press). Herring gull aversion to gaze in urban and rural human settlements. Animal Behaviour
Inzani E, Kelley L, Boogert N (In Press). Object neophilia in wild herring gulls in urban and rural locations.
Journal of Avian BiologyAbstract:
Object neophilia in wild herring gulls in urban and rural locations
Living with increasing urbanisation and human populations requires resourcefulness and flexibility in wild animals’ behaviour. Animals have to adapt to anthropogenic novelty in habitat structure and resources that may not resemble, or be as beneficial as, natural resources. Herring gulls (Larus argentatus) increasingly reside in towns and cities to breed and forage, yet how gulls are adjusting their behaviour to life in urban areas is not yet fully understood. This study investigated wild herring gulls’ responses to novel and common anthropogenic objects in urban and rural locations. We also examined whether gulls’ age influenced their object response behaviour. We found that, out of the 126 individual gulls presented with objects, 34% approached them. This suggests that the majority of targeted gulls were wary or lacked interest in the experimental set-up. of the 43 gulls that approached the objects, we found that those tested in urban locations approached more slowly than their rural counterparts. Overall, gulls showed no preference for either novel or common anthropogenic objects, and age did not influence likelihood of approach, approach speed or object choice. Individuals paid most attention to the object they approached first, potentially indicative of individual preferences. Our findings indicate that most herring gulls are not as attracted to anthropogenic objects as anecdotal reports have suggested. Covering up obvious food rewards may thus help mitigate human-gull conflict over anthropogenic food sources.
Abstract.
Kendal RL, Boogert NJ, Rendell L, Laland KN, Webster M, Jones PL (In Press). Social learning strategies: bridge-building between fields. Trends in Cognitive Sciences
Goumas M, Boogert N, Kelley L (In Press). Urban herring gulls use human behavioural cues to locate food. Royal Society Open Science
2023
Raghav S, Boogert NJ (2023). Factors associated with Herring Gulls<i>Larus argentatus</i>stealing food from humans in coastal towns. Bird Study, 69(3-4), 103-108.
2022
Saliveros AM, Bowden-Parry M, McAusland F, Boogert NJ (2022). Captive Asian short-clawed otters (Aonyx cinereus) learn to exploit unfamiliar natural prey.
R Soc Open Sci,
9(6).
Abstract:
Captive Asian short-clawed otters (Aonyx cinereus) learn to exploit unfamiliar natural prey.
Foraging plays a vital role in animal life histories, and learning whether unfamiliar food items are palatable is a key part of this process. Animals that engage in extractive foraging must also learn how to overcome the protective measures of their prey. While otters (subfamily Lutrinae) are a taxon known for their extractive foraging behaviour, how they learn about prey palatability and acquire extractive foraging techniques remains poorly understood. Here we investigated (i) how captive Asian short-clawed otters (Aonyx cinereus) learned to interact with, and extract meat from, unfamiliar natural prey and (ii) how their exploitation of such prey compared to their ability to overcome artificial foraging tasks containing familiar food rewards. Network-based diffusion analysis showed that otters learned to interact with unfamiliar natural prey by observing their group mates. However, once interacting with the prey, they learned to extract the meat mainly asocially. In addition, otters took longer to overcome the protective measures of unfamiliar natural prey than those of extractive food puzzles. Asian short-clawed otter populations are declining in the wild. Increasing our understanding of how they learn to overcome novel foraging challenges could help develop pre-release training procedures as part of reintroduction programmes for otter conservation.
Abstract.
Author URL.
Dehnen T, Papageorgiou D, Nyaguthii B, Cherono W, Penndorf J, Boogert NJ, Farine DR (2022). Costs dictate strategic investment in dominance interactions.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES,
377(1845).
Author URL.
Gomes ACR, Beltrao P, Boogert NJ, Cardoso GC (2022). Familiarity, dominance, sex and season shape common waxbill social networks.
BEHAVIORAL ECOLOGY,
33(3), 526-540.
Author URL.
Riley RJ, Gillie ER, Savage JL, Manica A, Boogert NJ (2022). Familiarity, personality, and foraging performance in three-spined sticklebacks.
Behav Processes,
200Abstract:
Familiarity, personality, and foraging performance in three-spined sticklebacks.
Animals can gain large benefits from living in groups but must coordinate with their groupmates in order to do so. Social interactions between groupmates drive overall group coordination and are influenced by the characteristics of individual group members. In particular, consistent inter-individual differences in behaviour (e.g. boldness) and familiarity between individuals in groups profoundly affect the individual interactions that mediate group coordination. However, the effects of boldness and familiarity have mostly been studied in isolation. Here we describe how familiarity and boldness interact to affect individual performance, leadership, and group coordination in small shoals of three-spined sticklebacks (Gasterosteus aculeatus) solving a novel foraging task. Groups of higher average boldness were less cohesive, but only when group members were familiar with one another. Familiarity affected shy and bold individuals' foraging performance and leadership tendencies differently depending on group characteristics: the shyest group member experienced declining foraging success and leadership with increased group boldness in familiar groups, but experienced the opposite effect on foraging and no effect on leadership in unfamiliar groups. The boldest group member, in contrast, exhibited the opposite pattern: leading and eating more with increasing group boldness in familiar groups, but eating less with increasing group boldness in unfamiliar groups. These results suggest that both boldness and familiarity are important for establishing group behaviour and coordination, and that consistent inter-individual differences in behaviour may primarily impact group coordination once familiarity has been established.
Abstract.
Author URL.
Dehnen T, Arbon JJ, Farine DR, Boogert NJ (2022). How feedback and feed-forward mechanisms link determinants of social dominance.
Biol Rev Camb Philos Soc,
97(3), 1210-1230.
Abstract:
How feedback and feed-forward mechanisms link determinants of social dominance.
In many animal societies, individuals differ consistently in their ability to win agonistic interactions, resulting in dominance hierarchies. These differences arise due to a range of factors that can influence individuals' abilities to win agonistic interactions, spanning from genetically driven traits through to individuals' recent interaction history. Yet, despite a century of study since Schjelderup-Ebbe's seminal paper on social dominance, we still lack a general understanding of how these different factors work together to determine individuals' positions in hierarchies. Here, we first outline five widely studied factors that can influence interaction outcomes: intrinsic attributes, resource value asymmetry, winner-loser effects, dyadic interaction-outcome history and third-party support. A review of the evidence shows that a variety of factors are likely important to interaction outcomes, and thereby individuals' positions in dominance hierarchies, in diverse species. We propose that such factors are unlikely to determine dominance outcomes independently, but rather form part of feedback loops whereby the outcomes of previous agonistic interactions (e.g. access to food) impact factors that might be important in subsequent interactions (e.g. body condition). We provide a conceptual framework that illustrates the multitude potential routes through which such feedbacks can occur, and how the factors that determine the outcomes of dominance interactions are highly intertwined and thus rarely act independently of one another. Further, we generalise our framework to include multi-generational feed-forward mechanisms: how interaction outcomes in one generation can influence the factors determining interaction outcomes in the next generation via a range of parental effects. This general framework describes how interaction outcomes and the factors determining them are linked within generations via feedback loops, and between generations via feed-forward mechanisms. We then highlight methodological approaches that will facilitate the study of feedback loops and dominance dynamics. Lastly, we discuss how our framework could shape future research, including: how feedbacks generate variation in the factors discussed, and how this might be studied experimentally; how the relative importance of different feedback mechanisms varies across timescales; the role of social structure in modulating the effect of feedbacks on hierarchy structure and stability; and the routes of parental influence on the dominance status of offspring. Ultimately, by considering dominance interactions as part of a dynamic feedback system that also feeds forward into subsequent generations, we will understand better the factors that structure dominance hierarchies in animal groups.
Abstract.
Author URL.
Barrett LP, Marsh JL, Boogert NJ, Templeton CN, Benson-Amram S (2022). Links between personality traits and problem-solving performance in zebra finches (. <i>Taeniopygia guttata</i>. ).
Royal Society Open Science,
9(6).
Abstract:
Links between personality traits and problem-solving performance in zebra finches (. Taeniopygia guttata. )
Consistent individual differences in behaviour across time or contexts (i.e. personality types) have been found in many species and have implications for fitness. Likewise, individual variation in cognitive abilities has been shown to impact fitness. Cognition and personality are complex, multidimensional traits. However, previous work has generally examined the connection between a single personality trait and a single cognitive ability, yielding equivocal results. Links between personality and cognitive ability suggest that behavioural traits coevolved and highlight their nuanced connections. Here we examined individuals' performance on multiple personality tests and repeated problem-solving tests (each measuring innovative performance). We assessed behavioural traits (dominance, boldness, activity, risk-taking, aggressiveness and obstinacy) in 41 captive zebra finches. Birds' scores for boldness and obstinacy were consistent over two years. We also examined whether personality correlated with problem-solving performance on repeated tests. Our results indicate that neophobia, dominance and obstinacy were related to successful solving, and less dominant, more obstinate birds solved the tasks quicker on average. Our results indicate the importance of examining multiple measures over a long period. Future work that identifies links between personality and innovation in non-model organisms may elucidate the coevolution of these two forms of individual differences.
Abstract.
Goumas M, Boogert NJ, Kelley LA, Holding T (2022). Predator or provider? How wild animals respond to mixed messages from humans.
Royal Society Open Science,
9(3).
Abstract:
Predator or provider? How wild animals respond to mixed messages from humans
Wild animals encounter humans on a regular basis, but humans vary widely in their behaviour: whereas many people ignore wild animals, some people present a threat, while others encourage animals' presence through feeding. Humans thus send mixed messages to which animals must respond appropriately to be successful. Some species appear to circumvent this problem by discriminating among and/or socially learning about humans, but it is not clear whether such learning strategies are actually beneficial in most cases. Using an individual-based model, we consider how learning rate, individual recognition (IR) of humans, and social learning (SL) affect wild animals' ability to reach an optimal avoidance strategy when foraging in areas frequented by humans. We show that ‘true’ IR of humans could be costly. We also find that a fast learning rate, while useful when human populations are homogeneous or highly dangerous, can cause unwarranted avoidance in other scenarios if animals generalize. SL reduces this problem by allowing conspecifics to observe benign interactions with humans. SL and a fast learning rate also improve the viability of IR. These results provide an insight into how wild animals may be affected by, and how they may cope with, contrasting human behaviour.
Abstract.
Di Giovanni J, Fawcett TW, Templeton CN, Raghav S, Boogert NJ (2022). Urban gulls show similar thermographic and behavioral responses to human shouting and conspecific alarm calls.
Frontiers in Ecology and Evolution,
10Abstract:
Urban gulls show similar thermographic and behavioral responses to human shouting and conspecific alarm calls
Rapid population growth and the urbanization of modern environments are markedly increasing human-wildlife conflict. Wild animals in urban landscapes can benefit from exploiting human resources, but are also exposed to increased risk of human-caused injury, which should favor the ability to perceive and respond to human cues. Although it is well known that domesticated animals use human cues that may indicate threats, less is known about wild animals living in urban environments. Herring gulls (Larus argentatus) in urban landscapes have adapted kleptoparasitic behaviors to obtain human food, often resulting in negative interactions with humans. Here we quantified both the behavioral and physiological responses of free-living urban herring gulls to human shouting. We presented urban gulls with a fake human food item and played back recordings of either a man shouting, a natural stressor (i.e. conspecific alarm call), or a neutral stimulus (i.e. robin song). We recorded behavioral responses and used non-invasive infrared thermography to measure eye-region surface temperature changes associated with the avian physiological stress response. We found that gulls exposed to shouting and to conspecific alarm calls showed similar changes in behavior (indicating high levels of vigilance) and eye-region surface temperature (indicating physiological stress). Both responses were significantly stronger than the responses to robin song. Additionally, the behavioral and physiological responses were positively correlated across individuals. Our results demonstrate that urban-dwelling gulls respond to human shouting and conspecific alarm calls in a similar way, and suggest that infrared thermography is a viable technique to monitor stress responses in free-living birds.
Abstract.
Dibnah AJ, Herbert-Read JE, Boogert NJ, McIvor GE, Jolles JW, Thornton A (2022). Vocally mediated consensus decisions govern mass departures from jackdaw roosts.
Curr Biol,
32(10), R455-R456.
Abstract:
Vocally mediated consensus decisions govern mass departures from jackdaw roosts.
In the early morning, large groups of up to hundreds or even thousands of roosting birds, sometimes comprising the entire roost population, often take off together in sudden mass departures. These departures commonly occur in low-light conditions and structurally complex habitats where access to visual cues is likely to be restricted. Roosting birds are often highly vocal, leading us to hypothesise that vocalisations, which can propagate over large distances, could provide a means of enabling individuals to agree on when to depart - that is to establish a consensus1 - and thus coordinate the timing of mass movements. Investigations of the role of acoustic signals in coordinating collective decisions have been limited to honeybees2 and relatively small vertebrate groups (
Abstract.
Author URL.
2021
Dehnen T, Papageorgiou D, Nyaguthii B, Cherono W, Penndorf J, Boogert NJ, Farine DR (2021). Costs dictate strategic investment in dominance interactions.
Evans JC, Hodgson DJ, Boogert NJ, Silk MJ (2021). Group size and modularity interact to shape the spread of infection and information through animal societies.
BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY,
75(12).
Author URL.
Dehnen T, Arbon JJ, Farine DR, Boogert N (2021). How feedback and feed-forward mechanisms link determinants of social dominance.
Gomes ACR, Boogert NJ, Cardoso GC (2021). Network structure and the optimization of proximity-based association criteria.
METHODS IN ECOLOGY AND EVOLUTION,
12(1), 88-100.
Author URL.
Allen SF, Ellis F, Mitchell C, Wang X, Boogert NJ, Lin C-Y, Clokey J, Thomas KV, Blount JD (2021). Phthalate diversity in eggs and associations with oxidative stress in the European herring gull (Larus argentatus). Marine Pollution Bulletin, 169, 112564-112564.
2020
Bowden-Parry M, Postma E, Boogert NJ (2020). Effects of food type and abundance on begging and sharing in Asian small-clawed otters (Aonyx cinereus).
PeerJ,
8Abstract:
Effects of food type and abundance on begging and sharing in Asian small-clawed otters (Aonyx cinereus)
Begging for food, a conspicuous solicitation display, is common in a variety of taxa, and it has received extensive research attention in a parent-offspring context. Both theoretical models and empirical evidence suggest that offspring begging can be an honest signal of hunger or a mediator of competition between siblings. At a behavioural mechanistic level, begging for food can be a form of harassment aimed at persuading those in possession of food to share. Food sharing, defined as the transfer of a defendable food item from one individual to another, can vary considerably between species, age-classes and food type and abundance. We investigated the determinants of begging and food-sharing behaviours in Asian small-clawed otters (Aonyx cinereus), a group-living species that commonly exhibits begging in captivity. We presented two captive otter populations with three food types that varied in exploitation complexity, in three different abundances. We predicted that begging rates would be highest when food was in lowest abundance and hardest to exploit, and that increased begging would lead to increased food sharing. We found that, over time, increased begging rates were indeed correlated with increased food transfers, but neither food type complexity nor abundance affected begging or sharing rates. However, age category was significantly associated with begging and food sharing rates: juvenile otters begged more and shared less than adult otters. The results from this first experimental study on begging and food sharing within the Mustelid family begin to reveal some of the drivers of these behaviours.
Abstract.
Evans JC, Silk MJ, Boogert NJ, Hodgson DJ (2020). Infected or informed? Social structure and the simultaneous transmission of information and infectious disease. Oikos, 129(9), 1271-1288.
Evans J, Silk M, Boogert N, Hodgson DJ (2020). Infected or informed? Social structure and the simultaneous transmission of information and infectious disease.
Saliveros AM, Blyth EC, Easter C, Hume GV, McAusland F, Hoppitt W, Boogert NJ (2020). Learning strategies and long-term memory in Asian short-clawed otters (Aonyx cinereus).
ROYAL SOCIETY OPEN SCIENCE,
7(11).
Author URL.
Gomes ACR, Guerra S, Silva PA, Marques CI, Trigo S, Boogert NJ, Cardoso GC (2020). Proactive common waxbills make fewer mistakes in a cognitive assay, the detour-reaching task.
Behavioral Ecology and Sociobiology,
74(3).
Abstract:
Proactive common waxbills make fewer mistakes in a cognitive assay, the detour-reaching task
Abstract: Reactive individuals explore and make decisions more slowly than proactive individuals, paying more attention to external cues. Reactive personality types are therefore predicted to make fewer mistakes in cognitive tasks, especially in tests of inhibitory control and reversal learning that require individuals to adjust behavioral routines. However, empirical evidence for this is mixed, and work relating cognition to a broader set of phenotypic traits has been called for. Here, using the common waxbill (Estrilda astrild), we relate performance in a cognitive assay, the detour-reaching task, to differences in personality, while controlling for putative confounding factors (including sex, breath rate, body size, and mass). Contrary to theoretical predictions, we found that proactive individuals, rather than reactive, made fewer mistakes in the detour-reaching task. We used body size and mass as proxies for condition, but neither predicted personality type or cognitive performance, thus providing no support for the hypothesis that condition dependence mediates the association between proactive personality and detour-reaching performance. This work adds to a growing number of studies contributing conflicting findings on how animal personality relates to cognitive performance, which, together, appear to require novel theory and more nuanced predictions. Significance statement: Theory predicts that reactive personality types (i.e. slower-acting and more attentive individuals) should perform better on cognitive tasks that involve inhibiting a response to an irrelevant stimulus to reach food (inhibitory control). Tests of this hypothesis have generated contradictory results and studies that account for confounding factors are needed. We quantified performance in an inhibitory control assay among common waxbills (Estrilda astrild), while controlling for the largest set of confounding factors to date. Contrary to predictions, waxbills with a reactive personality made more mistakes in the cognitive assay. These and other recent findings suggest that a more nuanced theory on the relation between cognition and personality is necessary.
Abstract.
Goumas M, Lee VE, Boogert NJ, Kelley LA, Thornton A (2020). The Role of Animal Cognition in Human-Wildlife Interactions. Frontiers in Psychology, 11
Allison M-L, Reed R, Michels E, Boogert NJ (2020). The drivers and functions of rock juggling in otters.
Royal Society Open Science,
7(5), 200141-200141.
Abstract:
The drivers and functions of rock juggling in otters
. Object play refers to the seemingly non-functional manipulation of inanimate items when in a relaxed state. In juveniles, object play may help develop skills to aid survival. However, why adults show object play remains poorly understood. We studied potential drivers and functions of the well-known object play behaviour of rock juggling in Asian small-clawed (
. Aonyx cinereus
. ) and smooth-coated (
. Lutrogale perspicillata
. ) otters. These are closely related species, but Asian small-clawed otters perform extractive foraging movements to exploit crabs and shellfish while smooth-coated otters forage on fish. We thus predicted that frequent rock jugglers might be better at solving extractive foraging puzzles in the first species, but not the latter. We also assessed whether species, age, sex and hunger correlated with rock juggling frequency. We found that juvenile and senior otters juggled more than adults. However, rock juggling frequency did not differ between species or sexes. Otters juggled more when ‘hungry’, but frequent jugglers did not solve food puzzles faster. Our results suggest that rock juggling may be a misdirected behaviour when hungry and may facilitate juveniles' motor development, but it appears unrelated to foraging skills. We suggest future studies to reveal the ontogeny, evolution and welfare implications of this object play behaviour.
.
Abstract.
2019
Hackett PMW, Shaw RC, Boogert NJ, Clayton NS (2019). A Facet Theory Analysis of the Structure of Cognitive Performance in New Zealand Robins (Petroica longipes).
International Journal of Comparative Psychology,
32, 1-16.
Abstract:
A Facet Theory Analysis of the Structure of Cognitive Performance in New Zealand Robins (Petroica longipes)
In this report, we analyzed the cognitive performance of New Zealand robins (Petroica longipes) using facet theory, smallestspace analysis (SSA), and partial order scalogram analysis (POSA). The data set we analyzed was originally subjected to principle component analysis in order to develop a test battery for avian cognitive performance. We extended these analyses by proposing a two facet, rather than a single component, solution using SSA, and we characterized individual birds by their scores on all tasks using POSA. We note problems with the small sample size and call for our exploratory analyses to be replicated using a larger sample of birds and for the development of further test items using the facet theory's tool, the mapping sentence. We suggest that facet theory and the mapping sentences are research approaches suitable for conceiving, designing, analyzing, and developing theory that may be used within avian cognitive research. We conclude that in our methodological comparison, facet-theory-designed research offers a useful alternative approach to principal component analysis when investigating avian cognition.
Abstract.
Thornton A, Boogert NJ (2019). Animal Cognition: the Benefits of Remembering.
Current Biology,
29(9), R324-R327.
Abstract:
Animal Cognition: the Benefits of Remembering
How cognitive abilities evolve through natural selection is poorly understood. Two new studies show that a good spatial memory helps birds that hide their food to survive and produce more offspring.
Abstract.
Lefebvre L, Boogert NJ (2019). Avian social learning. In (Ed)
Encyclopedia of Animal Behavior, 334-340.
Abstract:
Avian social learning
Abstract.
Riley RJ, Gillie ER, Horswill C, Johnstone RA, Boogert NJ, Manica A (2019). Coping with strangers: how familiarity and active interactions shape group coordination in Corydoras aeneus.
R Soc Open Sci,
6(9).
Abstract:
Coping with strangers: how familiarity and active interactions shape group coordination in Corydoras aeneus.
Social groups composed of familiar individuals exhibit better coordination than unfamiliar groups; however, the ways familiarity contributes to coordination are poorly understood. Prior social experience probably allows individuals to learn the tendencies of familiar group-mates and respond accordingly. Without prior experience, individuals would benefit from strategies for enhancing coordination with unfamiliar others. We used a social catfish, Corydoras aeneus, that uses discrete, observable tactile interactions to assess whether active interactions could facilitate coordination, and how their role might be mediated by familiarity. We describe this previously understudied physical interaction, 'nudges', and show it to be associated with group coordination and cohesion. Furthermore, we investigated nudging and coordination in familiar/unfamiliar pairs. In all pairs, we found that nudging rates were higher during coordinated movements than when fish were together but not coordinating. We observed no familiarity-based difference in coordination or cohesion. Instead, unfamiliar pairs exhibited significantly higher nudging rates, suggesting that unfamiliar pairs may be able to compensate for unfamiliarity through increased nudging. By contrast, familiar individuals coordinated with comparatively little nudging. Second, we analysed nudging and cohesion within triplets of two familiar and one unfamiliar individual (where familiar individuals had a choice of partner). Although all individuals nudged at similar rates, the unfamiliar group-mate was less cohesive than its familiar group-mates and spent more time alone. Unfamiliar individuals that nudged their group-mates more frequently exhibited higher cohesion, indicating that nudging may facilitate cohesion for the unfamiliar group-mate. Overall, our results suggest that nudges can mitigate unfamiliarity, but that their usage is reduced in the case of familiar individuals, implying a cost is associated with the behaviour.
Abstract.
Author URL.
Goumas M, Burns I, Kelley LA, Boogert NJ (2019). Herring gulls respond to human gaze direction.
Biol Lett,
15(8).
Abstract:
Herring gulls respond to human gaze direction.
Human-wildlife conflict is one of the greatest threats to species populations worldwide. One species facing national declines in the UK is the herring gull (Larus argentatus), despite an increase in numbers in urban areas. Gulls in urban areas are often considered a nuisance owing to behaviours such as food-snatching. Whether urban gull feeding behaviour is influenced by human behavioural cues, such as gaze direction, remains unknown. We therefore measured the approach times of herring gulls to a food source placed in close proximity to an experimenter who either looked directly at the gull or looked away. We found that only 26% of targeted gulls would touch the food, suggesting that food-snatching is likely to be conducted by a minority of individuals. When gulls did touch the food, they took significantly longer to approach when the experimenter's gaze was directed towards them compared with directed away. However, inter-individual behaviour varied greatly, with some gulls approaching similarly quickly in both treatments, while others approached much more slowly when the experimenter was looking at them. These results indicate that reducing human-herring gull conflict may be possible through small changes in human behaviour, but will require consideration of behavioural differences between individual gulls.
Abstract.
Author URL.
Jolles JW, Briggs HD, Araya-Ajoy YG, Boogert NJ (2019). Personality, plasticity and predictability in sticklebacks: bold fish are less plastic and more predictable than shy fish.
Animal Behaviour,
154, 193-202.
Abstract:
Personality, plasticity and predictability in sticklebacks: bold fish are less plastic and more predictable than shy fish
It is well established that animals often differ consistently from one another in their behaviour. Most work has focused on consistent differences in average behaviour, generally referred to as ‘animal personality’. However, individuals may also differ consistently from one another in how they change their behaviour over time or across environments, that is, plasticity, as well as in the predictability of their behaviour. How these three sources of behavioural variation are linked is rarely explored. Here we tested 80 wild-caught three-spined sticklebacks, Gasterosteus aculeatus, repeatedly over a 10-week period for their tendency to explore an open arena from the safety of cover, generally termed ‘boldness’. Using a mixed-modelling approach, we detected consistent individual differences in boldness, as well as in the extent to which fish changed this behaviour over time, that is, temporal plasticity. Boldness and plasticity were negatively correlated, with shy fish spending increasing amounts of time out of cover while bold fish changed little over time. After accounting for variation in personality and plasticity, we still detected individual differences in intraindividual behavioural variation (‘IIV’), that is, individual predictability. This residual variation was linked to fish’ boldness score, with shy fish having higher IIV and thus being less predictable in their behaviour than bold fish. After a 4-week break from testing, individuals on average decreased their time out of cover again to baseline levels. However, shyer, more plastic fish showed the largest changes in behaviour. Statistical simulations show that our experimental data set has sufficient statistical power to provide accurate and precise variance parameter estimates. Together, our results provide strong evidence that individual variation in boldness is linked with behavioural plasticity and predictability. Establishing the evolutionary causes as well as fitness consequences of these links in behavioural variation is an exciting challenge for future research.
Abstract.
Thornton A, Boogert NJ (2019). The nature and nurturing of animal minds. In Hosken DJ, Hunt J, Wedell N (Eds.) Genes and Behaviour Beyond Nature-Nurture, Wiley, 181-201.
Riley RJ, Gillie ER, Savage JL, Boogert NJ, Manica A, Jungwirth A (2019). The role of tactile interactions in flight responses in the Bronze Cory catfish (Corydoras aeneus).
Ethology,
125(11), 810-820.
Abstract:
The role of tactile interactions in flight responses in the Bronze Cory catfish (Corydoras aeneus)
One of the primary functions of animal aggregations is defence against predators. Many social animals enjoy reduced predation risk as a result of grouping, and individuals within groups can benefit from information transferred by their group-mates about a potential predator. We present evidence that a tactile interaction behaviour we term “nudging” substantially modified group responses to a potential threat in a highly social catfish, Corydoras aeneus. These catfish deployed nudges during flight responses, and these nudges were associated with a greater likelihood of group cohesion following a threat event. Increased nudging behaviour also resulted in longer flight responses, a potentially costly outcome in natural contexts. In addition, individuals that perceived the threat first were more likely to initiate nudges, implying that nudges could be used to alert group-mates to the presence of a threat. Taken together, our results suggest that tactile communication plays an important role in mediating anti-predator benefits from sociality in these fish.
Abstract.
2018
Logan CJ, Avin S, Boogert N, Buskell A, Cross FR, Currie A, Jelbert S, Lukas D, Mares R, Navarrete AF, et al (2018). Beyond brain size: Uncovering the neural correlates of behavioral and cognitive specialization.
Comparative Cognition and Behavior Reviews,
13, 55-90.
Abstract:
Beyond brain size: Uncovering the neural correlates of behavioral and cognitive specialization
Despite prolonged interest in comparing brain size and behavioral proxies of "intelligence" across taxa, the adaptive and cognitive significance of brain size variation remains elusive. Central to this problem is the continued focus on hominid cognition as a benchmark and the assumption that behavioral complexity has a simple relationship with brain size. Although comparative studies of brain size have been criticized for not reflecting how evolution actually operates, and for producing spurious, inconsistent results, the causes of these limitations have received little discussion. We show how these issues arise from implicit assumptions about what brain size measures and how it correlates with behavioral and cognitive traits. We explore how inconsistencies can arise through heterogeneity in evolutionary trajectories and selection pressures on neuroanatomy or neurophysiology across taxa. We examine how interference from ecological and life history variables complicates interpretations of brain-behavior correlations and point out how this problem is exacerbated by the limitations of brain and cognitive measures. These considerations, and the diversity of brain morphologies and behavioral capacities, suggest that comparative brain-behavior research can make greater progress by focusing on specific neuroanatomical and behavioral traits within relevant ecological and evolutionary contexts. We suggest that a synergistic combination of the "bottom-up" approach of classical neuroethology and the "top-down" approach of comparative biology/psychology within closely related but behaviorally diverse clades can limit the effects of heterogeneity, interference, and noise. We argue that this shift away from broad-scale analyses of superficial phenotypes will provide deeper, more robust insights into brain evolution.
Abstract.
Montgomer SH, Currie A, Lukas D, Boogert N, Buskell A, Cross FR, Jelbert S, Avin S, Mares R, Navarrete AF, et al (2018). Ingredients for understanding brain and behavioral evolution: Ecology, phylogeny, and mechanism.
Comparative Cognition and Behavior Reviews,
13, 99-104.
Abstract:
Ingredients for understanding brain and behavioral evolution: Ecology, phylogeny, and mechanism
Uncovering the neural correlates and evolutionary drivers of behavioral and cognitive traits has been held back by traditional perspectives on which correlations to look for-in particular, anthropocentric conceptions of cognition and coarse-grained brain measurements. We welcome our colleagues' comments on our overview of the field and their suggestions for how to move forward. Here, we counter, clarify, and extend some points, focusing on the merits of looking for the "best" predictor of cognitive ability, the sources and meaning of "noise," and the ways in which we can deduce and test meaningful conclusions from comparative analyses of complex traits.
Abstract.
Boogert NJ, Madden JR, Morand-Ferron J, Thornton A (2018). Measuring and understanding individual differences in cognition.
Philos Trans R Soc Lond B Biol Sci,
373(1756).
Abstract:
Measuring and understanding individual differences in cognition.
Individuals vary in their cognitive performance. While this variation forms the foundation of the study of human psychometrics, its broader importance is only recently being recognized. Explicitly acknowledging this individual variation found in both humans and non-human animals provides a novel opportunity to understand the mechanisms, development and evolution of cognition. The papers in this special issue highlight the growing emphasis on individual cognitive differences from fields as diverse as neurobiology, experimental psychology and evolutionary biology. Here, we synthesize this body of work. We consider the distinct challenges in quantifying individual differences in cognition and provide concrete methodological recommendations. In particular, future studies would benefit from using multiple task variants to ensure they target specific, clearly defined cognitive traits and from conducting repeated testing to assess individual consistency. We then consider how neural, genetic, developmental and behavioural factors may generate individual differences in cognition. Finally, we discuss the potential fitness consequences of individual cognitive variation and place these into an evolutionary framework with testable hypotheses. We intend for this special issue to stimulate researchers to position individual variation at the centre of the cognitive sciences.This article is part of the theme issue 'Causes and consequences of individual differences in cognitive abilities'.
Abstract.
Author URL.
Jolles JW, Laskowski KL, Boogert NJ, Manica A (2018). Repeatable group differences in the collective behaviour of stickleback shoals across ecological contexts.
Proc Biol Sci,
285(1872).
Abstract:
Repeatable group differences in the collective behaviour of stickleback shoals across ecological contexts.
Establishing how collective behaviour emerges is central to our understanding of animal societies. Previous research has highlighted how universal interaction rules shape collective behaviour, and that individual differences can drive group functioning. Groups themselves may also differ considerably in their collective behaviour, but little is known about the consistency of such group variation, especially across different ecological contexts that may alter individuals' behavioural responses. Here, we test if randomly composed groups of sticklebacks differ consistently from one another in both their structure and movement dynamics across an open environment, an environment with food, and an environment with food and shelter. Based on high-resolution tracking data of the free-swimming shoals, we found large context-associated changes in the average behaviour of the groups. But despite these changes and limited social familiarity among group members, substantial and predictable behavioural differences between the groups persisted both within and across the different contexts (group-level repeatability): some groups moved consistently faster, more cohesively, showed stronger alignment and/or clearer leadership than other groups. These results suggest that among-group heterogeneity could be a widespread feature in animal societies. Future work that considers group-level variation in collective behaviour may help understand the selective pressures that shape how animal collectives form and function.
Abstract.
Author URL.
Boogert NJ, Lachlan RF, Spencer KA, Templeton CN, Farine DR (2018). Stress hormones, social associations and song learning in zebra finches. Philosophical Transactions B: Biological Sciences
2017
Cauchard L, Angers B, Boogert NJ, Lenarth M, Bize P, Doligez B (2017). An experimental test of a causal link between problem-solving performance and reproductive success in wild great tits.
Frontiers in Ecology and Evolution,
5(SEP).
Abstract:
An experimental test of a causal link between problem-solving performance and reproductive success in wild great tits
Recent studies have uncovered relationships between measures of various cognitive performances and proxies of fitness such as reproductive success in non-human animals. However, to better understand the evolution of cognition in the wild, we still have to determine the causality of these relationships and the underlying mechanisms. The cognitive ability of an individual may directly influence its ability to raise many and/or high quality young through for example its provisioning ability. Conversely, large and/or high quality broods may lead to high parental motivation to solve problems related to their care. To answer this question, we manipulated reproductive success through brood size and measured subsequent problem-solving performance in wild great tit parents. Our results show that brood size manipulation did not affect the probability to solve the task. Moreover, solver pairs fledged more young than non-solver pairs independently of brood size treatment in one of the two experimental years and they showed higher nestling provisioning rate in both years. Overall, it shows that problem-solving performance was not driven by motivation and suggest that problem-solvers may achieve higher fledging success through higher provisioning rates. Our study constitutes a first key step toward a mechanistic understanding of the consequences of innovation ability for individual fitness in the wild.
Abstract.
Logan CJ, Avin S, Boogert N, Buskell A, Cross FR, Currie A, Jelbert S, Lukas D, Mares R, Navarrete AF, et al (2017). Beyond brain size.
Jolles JW, Boogert NJ, Sridhar VH, Couzin ID, Manica A (2017). Consistent individual differences drive collective behaviour and group functioning of schooling fish.
Boogert NJ (2017). Sing Me Something Smart: Does Song Signal Cognition?. In (Ed) Avian Cognition, 296-313.
Ladds Z, Hoppitt W, Boogert NJ (2017). Social learning in otters. Royal Society Open Science
Cauchard L, Doucet SM, Boogert NJ, Angers B, Doligez B (2017). The relationship between plumage colouration, problem-solving and learning performance in great tits Parus major.
Journal of Avian Biology,
48(9), 1246-1253.
Abstract:
The relationship between plumage colouration, problem-solving and learning performance in great tits Parus major
Recent studies suggest that individuals with better problem-solving and/or learning performance have greater reproductive success, and that individuals may thus benefit from choosing mates based on these performances. However, directly assessing these performances in candidate mates could be difficult. Instead, the use of indirect cues related to problem-solving and/or learning performance, such as condition-dependent phenotypic traits, might be favored. We investigated whether problem-solving and learning performance on a novel non-foraging task correlated with sexually selected plumage colouration in a natural population of great tits Parus major. We found that males successful in solving the task had darker blue-black crowns than non-solvers, and that males solving the task more rapidly over multiple attempts (i.e. learners) exhibited blue-black crowns with higher UV chroma and shorter-wavelength hues than non-learners. In contrast, we found no link between behavioural performance on the task and the yellow breast colouration in either sex. Our findings suggest that blue-black crown colouration could serve as a signal of problem-solving and learning performance in wild great tit males. Further research remains necessary to determine whether different sexually selected traits are used to signal cognitive performance for mate choice, either directly (i.e. cognitive performance influencing individual's health and ornamentation through diet for example) or indirectly (i.e. due to a correlation with a third factor such as individual quality or condition).
Abstract.
Zimmer C, Larriva M, Boogert NJ, Spencer KA (2017). Transgenerational transmission of a stress-coping phenotype programmed by early-life stress in the Japanese quail.
Sci Rep,
7Abstract:
Transgenerational transmission of a stress-coping phenotype programmed by early-life stress in the Japanese quail.
An interesting aspect of developmental programming is the existence of transgenerational effects that influence offspring characteristics and performance later in life. These transgenerational effects have been hypothesized to allow individuals to cope better with predictable environmental fluctuations and thus facilitate adaptation to changing environments. Here, we test for the first time how early-life stress drives developmental programming and transgenerational effects of maternal exposure to early-life stress on several phenotypic traits in their offspring in a functionally relevant context using a fully factorial design. We manipulated pre- and/or post-natal stress in both Japanese quail mothers and offspring and examined the consequences for several stress-related traits in the offspring generation. We show that pre-natal stress experienced by the mother did not simply affect offspring phenotype but resulted in the inheritance of the same stress-coping traits in the offspring across all phenotypic levels that we investigated, shaping neuroendocrine, physiological and behavioural traits. This may serve mothers to better prepare their offspring to cope with later environments where the same stressors are experienced.
Abstract.
Author URL.
Griffith SC, Crino OL, Andrew SC, Nomano FY, Adkins-Regan E, Alonso-Alvarez C, Bailey IE, Bittner SS, Bolton PE, Boner W, et al (2017). Variation in Reproductive Success Across Captive Populations: Methodological Differences, Potential Biases and Opportunities.
Ethology,
123(1), 1-29.
Abstract:
Variation in Reproductive Success Across Captive Populations: Methodological Differences, Potential Biases and Opportunities
Our understanding of fundamental organismal biology has been disproportionately influenced by studies of a relatively small number of ‘model’ species extensively studied in captivity. Laboratory populations of model species are commonly subject to a number of forms of past and current selection that may affect experimental outcomes. Here, we examine these processes and their outcomes in one of the most widely used vertebrate species in the laboratory – the zebra finch (Taeniopygia guttata). This important model species is used for research across a broad range of fields, partly due to the ease with which it can be bred in captivity. However despite this perceived amenability, we demonstrate extensive variation in the success with which different laboratories and studies bred their subjects, and overall only 64% of all females that were given the opportunity, bred successfully in the laboratory. We identify and review several environmental, husbandry, life-history and behavioural factors that potentially contribute to this variation. The variation in reproductive success across individuals could lead to biases in experimental outcomes and drive some of the heterogeneity in research outcomes across studies. The zebra finch remains an excellent captive animal system and our aim is to sharpen the insight that future studies of this species can provide, both to our understanding of this species and also with respect to the reproduction of captive animals more widely. We hope to improve systematic reporting methods and that further investigation of the issues we raise will lead both to advances in our fundamental understanding of avian reproduction as well as to improvements in future welfare and experimental efficiency.
Abstract.
2016
Cauchard L, Angers B, Boogert NJ, Doligez B (2016). Effect of an anti-malaria drug on behavioural performance on a problem-solving task: an experiment in wild great tits.
Behavioural Processes,
133, 24-30.
Abstract:
Effect of an anti-malaria drug on behavioural performance on a problem-solving task: an experiment in wild great tits
Malaria parasites have been shown to decrease host fitness in several species in the wild and their detrimental effects on host cognitive ability are well established in humans. However, experimental demonstrations of detrimental effects on non-human host behaviour are currently limited. In this study, we experimentally tested whether injections of an anti-malaria drug affected short-term behavioural responses to a problem-solving task during breeding in a wild population of great tits (Parus major) naturally infected with malaria. Adult females treated against malaria were more active than control females, even though they were not more likely to solve the task or learn how to do so, suggesting that energetic constraints could shape differences in some behaviours while changes in cognitive performances might require more time for the neural system to recover or may depend mainly on infection at the developmental stage. Alternatively, parasite load might be a consequence, rather than a cause, of inter-individual variation in cognitive performance. These results also suggest that inter-individual as well as inter-population differences in some behavioural traits may be linked to blood parasite load.
Abstract.
Jolles JW, Manica A, Boogert NJ (2016). Food intake rates of inactive fish are positively linked to boldness in three-spined sticklebacks Gasterosteus aculeatus.
Journal of Fish Biology,
88(4), 1661-1668.
Abstract:
Food intake rates of inactive fish are positively linked to boldness in three-spined sticklebacks Gasterosteus aculeatus
To investigate the link between personality and maximum food intake of inactive individuals, food-deprived three-spined sticklebacks Gasterosteus aculeatus at rest in their home compartments were provided with ad libitum prey items. Bolder individuals ate considerably more than shyer individuals, even after accounting for body size, while sociability did not have an effect. These findings support pace-of-life theory predicting that life-history strategies are linked to boldness.
Abstract.
2015
Farine DR, Spencer KA, Boogert NJ (2015). Early-life stress triggers juvenile zebra finches to switch social learning strategies.
Current Biology,
25(16), 2184-2188.
Abstract:
Early-life stress triggers juvenile zebra finches to switch social learning strategies
Stress during early life can cause disease and cognitive impairment in humans and non-humans alike [1]. However, stress and other environmental factors can also program developmental pathways [2, 3]. We investigate whether differential exposure to developmental stress can drive divergent social learning strategies [4, 5] between siblings. In many species, juveniles acquire essential foraging skills by copying others: they can copy peers (horizontal social learning), learn from their parents (vertical social learning), or learn from other adults (oblique social learning) [6]. However, whether juveniles' learning strategies are condition dependent largely remains a mystery. We found that juvenile zebra finches living in flocks socially learned novel foraging skills exclusively from adults. By experimentally manipulating developmental stress, we further show that social learning targets are phenotypically plastic. While control juveniles learned foraging skills from their parents, their siblings, exposed as nestlings to experimentally elevated stress hormone levels, learned exclusively from unrelated adults. Thus, early-life conditions triggered individuals to switch strategies from vertical to oblique social learning. This switch could arise from stress-induced differences in developmental rate, cognitive and physical state, or the use of stress as an environmental cue. Acquisition of alternative social learning strategies may impact juveniles' fit to their environment and ultimately change their developmental trajectories.
Abstract.
Jolles JW, Boogert NJ, van den Bos R (2015). Sex differences in risk-taking and associative learning in rats.
Royal Society Open Science,
2(11).
Abstract:
Sex differences in risk-taking and associative learning in rats
In many species, males tend to have lower parental investment than females and greater variance in their reproductive success. Males might therefore be expected to adopt more high-risk, high-return behaviours than females. Next to risk-taking behaviour itself, sexes might also differ in how they respond to information and learn new associations owing to the fundamental link of these cognitive processes with the risk–reward axis. Here we investigated sex differences in both risk-taking and learned responses to risk by measuring male and female rats’ (Rattus norvegicus) behaviour across three contexts in an open field test containing cover. We found that when the environment was novel, males spent more time out of cover than females. Males also hid less when exposed to the test arena containing predator odour. By contrast, females explored more than males when the predator odour was removed (associatively learned risk). These results suggest that males are more risk-prone but behave more in line with previous experiences, while females are more risk-averse and more responsive to changes in their current environment. Our results suggest that male and female rats differ in how they cope with risk and highlight that a general link may exist between risk-taking behaviour and learning style.
Abstract.
Shaw RC, Boogert NJ, Clayton NS, Burns KC (2015). Wild psychometrics: Evidence for 'general' cognitive performance in wild New Zealand robins, Petroica longipes.
Animal Behaviour,
109, 101-111.
Abstract:
Wild psychometrics: Evidence for 'general' cognitive performance in wild New Zealand robins, Petroica longipes
In human psychometric testing, individuals' scores in tests of diverse cognitive processes are positively correlated, with a 'general intelligence' factor (. g) typically accounting for at least 40% of total variance. Individual differences in cognitive ability have been extensively studied in humans, yet they have received far less attention in nonhuman animals. In particular, the development of a test battery suitable for quantifying individual cognitive performance in birds remains in its infancy. Additionally, implementing this approach in the wild, where the ecological significance of cognition can also be explored, presents considerable logistical challenges for most species. We developed a cognitive test battery for wild New Zealand North Island robins. Our battery comprised six tasks based on established measures of avian cognitive performance: a motor task, colour and shape discrimination, reversal learning, spatial memory and inhibitory control. Robins varied greatly in their ability to solve these tasks and we found weakly positive, nonsignificant correlations between most tasks. A principal components analysis of task performances yielded two factors with eigenvalues >1. The first component extracted explained over 34% of the variance in cognitive performance and all six tasks loaded positively on this first component. We show, using randomization tests, that these results are robust. Our results thus suggest that a general cognitive factor, analogous to human g, underpins cognitive performance in wild North Island robins tested in their natural habitat.
Abstract.
2014
Boogert NJ, Farine DR, Spencer KA (2014). Developmental stress predicts social network position.
Biology Letters,
10(10).
Abstract:
Developmental stress predicts social network position
The quantity and quality of social relationships, as captured by social network analysis, can have major fitness consequences. Various studies have shown that individual differences in social behaviour can be due to variation in exposure to developmental stress. However, whether these developmental differences translate to consistent differences in social network position is not known. We experimentally increased levels of the avian stress hormone corticosterone (CORT) in nestling zebra finches in a fully balanced design. Upon reaching nutritional independence, we released chicks and their families into two free-flying rooms, where we measured daily social networks over five weeks using passive integrated transponder tags. Developmental stress had a significant effect on social behaviour: despite having similar foraging patterns, CORT chicks had weaker associations to their parents than control chicks. Instead, CORT chicks foraged with a greater number of flock mates and were less choosy with whom they foraged, resulting in more central network positions. These findings highlight the importance of taking developmental history into account to understand the drivers of social organization in gregarious species.
Abstract.
Templeton CN, Laland KN, Boogert NJ (2014). Does song complexity correlate with problem-solving performance inflocks of zebra finches?.
Animal Behaviour,
92, 63-71.
Abstract:
Does song complexity correlate with problem-solving performance inflocks of zebra finches?
The 'cognitive capacity hypothesis' states that song complexity could potentially be used by prospective mates to assess an individual's overall cognitive ability. Several recent studies have provided support for the cognitive capacity hypothesis, demonstrating that individuals with more complex songs or larger song repertoires performed better on various learning tasks. These studies all measured individuals' learning performance in social isolation. However, for gregarious species such as the zebra finch, Taeniopygia guttata, testing individuals in a group context is socially and ecologically more relevant if song complexity is to be a meaningful indicator of cognitive ability. We tested whether song complexity correlated with performance on a suite of novel foraging problems in flocks of male zebra finches, starting by replicating the lid-flipping task used by Boogert etal. (Animal Behaviour, 2008, 76, 1735-1741), who provided the first support for the cognitive capacity hypothesis in zebra finches isolated during testing. We also presented flocks with a barrier task and two types of novel food. We found that males' song complexity scores did not correlate with their latency to solve any of these novel foraging problems in a social context. Individuals that solved the tasks likewise did not have more complex songs than nonsolvers. However, performance was positively correlated across the different foraging tasks. These results raise doubts as to whether the song complexity measures used by Boogert etal. are predictors of problem-solving performance, and perhaps cognitive ability, in a more ecologically relevant, social setting. Stress responsiveness might instead explain the association between song complexity and foraging task performance among isolated zebra finches reported by Boogert etal. © 2014 the Association for the Study of Animal Behaviour.
Abstract.
Zandberg L, Jolles JW, Boogert NJ, Thornton A (2014). Jackdaw nestlings can discriminate between conspecific calls but do not beg specifically to their parents.
Behavioral Ecology,
25(3), 565-573.
Abstract:
Jackdaw nestlings can discriminate between conspecific calls but do not beg specifically to their parents
The ability to recognize other individuals may provide substantial benefits to young birds, allowing them to target their begging efforts appropriately, follow caregivers after fledging, and establish social relationships later in life. Individual recognition using vocal cues is likely to play an important role in the social lives of birds such as corvids that provision their young postfledging and form stable social bonds, but the early development of vocal recognition has received little attention. We used playback experiments on jackdaws, a colonial corvid species, to test whether nestlings begin to recognize their parents' calls before fledging. Although the food calls made by adults when provisioning nestlings were individually distinctive, nestlings did not beg preferentially to their parents' calls. Ten-day-old nestlings not only responded equally to the calls of their parents, neighboring jackdaws whose calls they were likely to overhear regularly and unfamiliar jackdaws from distant nest boxes, but also to the calls of rooks, a sympatric corvid species. Responses to rooks declined substantially with age, but 20- and 28-day-old nestlings were still equally likely to produce vocal and postural begging responses to parental and nonparental calls. This is unlikely to be due to an inability to discriminate between calls, as older nestlings did respond more quickly and with greater vocal intensity to familiar calls, with some indication of discrimination between parents and neighbors. These results suggest that jackdaws develop the perceptual and cognitive resources to discriminate between conspecific calls before fledging but may not benefit from selective begging responses. © the Author 2014.
Abstract.
Laland KN, Boogert N, Evans C (2014). Niche construction, innovation and complexity. Environmental Innovation and Societal Transitions, 11, 71-86.
Boogert NJ, Nightingale GF, Hoppitt W, Laland KN (2014). Perching but not foraging networks predict the spread of novel foraging skills in starlings.
Behavioural Processes,
109(PB), 135-144.
Abstract:
Perching but not foraging networks predict the spread of novel foraging skills in starlings
The directed social learning hypothesis suggests that information does not spread evenly through animal groups, but rather individual characteristics and patterns of physical proximity guide the social transmission of information along specific pathways. Network-based diffusion analysis (NBDA) allows researchers to test whether information spreads following a social network. However, the explanatory power of different social networks has rarely been compared, and current models do not easily accommodate random effects (e.g. allowing for individuals within groups to correlate in their asocial solving rates). We tested whether the spread of two novel foraging skills through captive starling groups was affected by individual- and group-level random and fixed effects (i.e. sex, age, body condition, dominance rank and demonstrator status) and perching or foraging networks. We extended NBDA to include random effects and conducted model discrimination in a Bayesian context. We found that social learning increased the rate at which birds acquired the novel foraging task solutions by 6.67 times, and acquiring one of the two novel foraging task solutions facilitated the asocial acquisition of the other. Surprisingly, the spread of task solutions followed the perching rather than the foraging social network. Upon acquiring a task solution, foraging performance was facilitated by the presence of group mates. Our results highlight the importance of considering more than one social network when predicting the spread of information through animal groups. This article is part of a Special Issue entitled: Cognition in the wild.
Abstract.
Nightingale G, Boogert NJ, Laland KN, Hoppitt W (2014). Quantifying diffusion in social networks: a Bayesian approach. In (Ed) Animal Social Networks, 38-52.
MacLean EL, Hare B, Nun CL, Addess E, Amic F, Anderson RC, Aureli F, Baker JM, Bania AE, Barnard AM, et al (2014). The evolution of self-control.
Proceedings of the National Academy of Sciences of the United States of America,
111(20).
Abstract:
The evolution of self-control
Cognition presents evolutionary research with one of its greatest challenges. Cognitive evolution has been explained at the proximate level by shifts in absolute and relative brain volume and at the ultimate level by differences in social and dietary complexity. However, no study has integrated the experimental and phylogenetic approach at the scale required to rigorously test these explanations. Instead, previous research has largely relied on various measures of brain size as proxies for cognitive abilities. We experimentally evaluated these major evolutionary explanations by quantitatively comparing the cognitive performance of 567 individuals representing 36 species on two problem-solving tasks measuring self-control. Phylogenetic analysis revealed that absolute brain volume best predicted performance across species and accounted for considerably more variance than brain volume controlling for body mass. This result corroborates recent advances in evolutionary neurobiology and illustrates the cognitive consequences of cortical reorganization through increases in brain volume. Within primates, dietary breadth but not social group size was a strong predictor of species differences in self-control. Our results implicate robust evolutionary relationships between dietary breadth, absolute brain volume, and self-control. These findings provide a significant first step toward quantifying the primate cognitive phenome and explaining the process of cognitive evolution.
Abstract.
2013
Seed AM, Boogert NJ (2013). Animal cognition: an end to insight?.
Current Biology,
23(2).
Abstract:
Animal cognition: an end to insight?
Once hailed as insightful, the string-pulling behaviour of birds may actually rely on immediate visual feedback rather than mental simulation or planning. But is this an end to the study of animal insight or a call for a new approach? © 2013 Elsevier Ltd all rights reserved.
Abstract.
Corfield JR, Birkhead TR, Spottiswoode CN, Iwaniuk AN, Boogert NJ, Gutiérrez-Ibáñez C, Overington SE, Wylie DR, Lefebvre L (2013). Brain size and morphology of the brood-parasitic and cerophagous honeyguides (Aves: Piciformes).
Brain, Behavior and Evolution,
81(3), 170-186.
Abstract:
Brain size and morphology of the brood-parasitic and cerophagous honeyguides (Aves: Piciformes)
Honeyguides (Indicatoridae, Piciformes) are unique among birds in several respects. All subsist primarily on wax, are obligatory brood parasites and one species engages in 'guiding' behavior in which it leads human honey hunters to bees' nests. This unique life history has likely shaped the evolution of their brain size and morphology. Here, we test that hypothesis using comparative data on relative brain and brain region size of honeyguides and their relatives: woodpeckers, barbets and toucans. Honeyguides have significantly smaller relative brain volumes than all other piciform taxa. Volumetric measurements of the brain indicate that honeyguides have a significantly larger cerebellum and hippocampal formation (HF) than woodpeckers, the sister clade of the honeyguides, although the HF enlargement was not significant across all of our analyses. Cluster analyses also revealed that the overall composition of the brain and telencephalon differs greatly between honeyguides and woodpeckers. The relatively smaller brains of the honeyguides may be a consequence of brood parasitism and cerophagy ('wax eating'), both of which place energetic constraints on brain development and maintenance. The inconclusive results of our analyses of relative HF volume highlight some of the problems associated with comparative studies of the HF that require further study. Copyright © 2013 S. Karger AG, Basel.
Abstract.
Zimmer C, Boogert NJ, Spencer KA (2013). Developmental programming: Cumulative effects of increased pre-hatching corticosterone levels and post-hatching unpredictable food availability on physiology and behaviour in adulthood.
Hormones and Behavior,
64(3), 494-500.
Abstract:
Developmental programming: Cumulative effects of increased pre-hatching corticosterone levels and post-hatching unpredictable food availability on physiology and behaviour in adulthood
Prolonged exposure to stress during development can have long-term detrimental effects on health and wellbeing. However, the environmental matching hypothesis proposes that developmental stress programs physiology and behaviour in an adaptive way that can enhance fitness if early environments match those experienced later in life. Most research has focused on the harmful effects that stress during a single period in early life may exert in adulthood. In this study, we tested the potential additive and beneficial effects that stress experienced during both pre- and post-hatching development may have on adult physiology and behaviour. Japanese quail experienced different stress-related treatments across two developmental life stages: pre-hatching corticosterone (CORT) injection, post-hatching unpredictable food availability, both pre- and post-hatching treatments, or control. In adulthood, we determined quails' acute stress response, neophobia and novel environment exploration. The pre-hatching CORT treatment resulted in attenuated physiological responses to an acute stressor, increased activity levels and exploration in a novel environment. Post-hatching unpredictable food availability decreased adults' latency to feed. Furthermore, there were cumulative effects of these treatments across the two developmental stages: quail subjected to both pre- and post-hatching treatments were the most explorative and risk-taking of all treatment groups. Such responses to novel environments could enhance survival in unpredictable environments in later life. Our data also suggest that these behavioural responses may have been mediated by long-term physiological programming of the adrenocortical stress response, creating phenotypes that could exhibit fitness-enhancing behaviours in a changing environment. © 2013 the Authors.
Abstract.
Boogert NJ, Arbilly M, Muth F, Seed AM (2013). Do crows reason about causes or agents? the devil is in the controls.
Proc Natl Acad Sci U S A,
110(4).
Author URL.
Boogert NJ, Zimmer C, Spencer KA (2013). Pre- and post-natal stress have opposing effects on social information use.
Biology Letters,
9(2).
Abstract:
Pre- and post-natal stress have opposing effects on social information use
Theoretical models of social learning predict that animals should copy others in variable environments where resource availability is relatively unpredictable. Although short-term exposure to unpredictable conditions in adulthood has been shown to encourage social learning, virtually nothing is known concerning whether and how developmental conditions affect social information use. Unpredictable food availability increases levels of the stress hormone corticosterone (CORT). In birds, CORT can be transferred from the mother to her eggs, and have downstream behavioural effects. We tested how pre-natal CORT elevation through egg injection, and chick post-natal development in unpredictable food conditions, affected social information use in adult Japanese quail (Coturnix japonica). Pre-natal CORT exposure encouraged quail to copy the foraging decisions of demonstrators in video playbacks, whereas post-natal food unpredictability led individuals to avoid the demonstrated food source. An individual's exposure to stress and uncertainty during development can thus affect its use of social foraging information in adulthood. However, the stressor's nature and developmental timing determine whether an adult will tend to copy conspecifics or do the opposite. Developmental effects on social information use might thus help explain individual differences in social foraging tactics and leadership. © 2013 the Author(s) Published by the Royal Society.
Abstract.
Cauchard L, Boogert NJ, Lefebvre L, Dubois F, Doligez B (2013). Problem-solving performance is correlated with reproductive success in a wild bird population.
Animal Behaviour,
85(1), 19-26.
Abstract:
Problem-solving performance is correlated with reproductive success in a wild bird population
Although interindividual variation in problem-solving ability is well documented, its relation to variation in fitness in the wild remains unclear. We investigated the relationship between performance on a problem-solving task and measures of reproductive success in a wild population of great tits, Parus major. We presented breeding pairs during the nestling provisioning period with a novel string-pulling task requiring the parents to remove an obstacle with their leg that temporarily blocked access to their nestbox. We found that nests where at least one parent solved the task had higher nestling survival until fledging than nests where both parents were nonsolvers. Furthermore, clutch size, hatching success and fledgling number were positively correlated with speed in solving the task. Our study suggests that natural selection may directly act on interindividual variation in problem-solving performance. In light of these results, the mechanisms maintaining between-individual variation in problem-solving performance in natural populations need further investigation. © 2012.
Abstract.
2011
Fawcett TW, Boogert NJ, Lefebvre L (2011). Female assessment: cheap tricks or costly calculations?.
BEHAVIORAL ECOLOGY,
22(3), 462-463.
Author URL.
Boogert NJ, Fawcett TW, Lefebvre L (2011). Mate choice for cognitive traits: a review of the evidence in nonhuman vertebrates.
BEHAVIORAL ECOLOGY,
22(3), 447-459.
Author URL.
Boogert NJ, Anderson RC, Peters S, Searcy WA, Nowicki S (2011). Song repertoire size in male song sparrows correlates with detour reaching, but not with other cognitive measures.
Animal Behaviour,
81(6), 1209-1216.
Abstract:
Song repertoire size in male song sparrows correlates with detour reaching, but not with other cognitive measures
Song learning is a cognitive task in which juvenile birds acquire, store and use information about adult song to shape their own song production. Comparative studies show that across bird species, performance on different cognitive tasks is usually positively correlated. If the same holds true within species, then the complexity of a male's learned song ought to be correlated with other cognitive abilities. To test this hypothesis, we measured correlations between song repertoire size and cognitive performance in wild song sparrows, Melospiza melodia. Females prefer males with larger song repertoires in this species, and song repertoire size correlates with various fitness measures. We recorded males' song repertoires in the field and tested these males in captivity on motor, colour association and reversal learning tasks, as well as on a detour-reaching task that measures inhibitory control. We found that individuals' performance on the colour association task correlated positively with their performance on the reversal task, but performance did not correlate across the other learning tasks. Males with larger song repertoires were faster to solve the detour-reaching task, but performed worse on the reversal task than males with smaller song repertoires. Although our results suggest that song repertoire size does correlate with one measure of cognitive performance, more detailed song analyses and further cognitive tests are required to answer the questions raised by our findings. © 2011 the Association for the Study of Animal Behaviour.
Abstract.
Overington SE, Morand-Ferron J, Boogert NJ, Lefebvre L (2011). Technical innovations drive the relationship between innovativeness and residual brain size in birds (vol 78, pg 1001, 2009).
ANIMAL BEHAVIOUR,
82(2), 421-421.
Author URL.
2010
Boogert NJ, Monceau K, Lefebvre L (2010). A field test of behavioural flexibility in Zenaida doves (Zenaida aurita).
Behavioural Processes,
85(2), 135-141.
Abstract:
A field test of behavioural flexibility in Zenaida doves (Zenaida aurita)
Animals' ability to adjust their behaviour when environmental conditions change can increase their likelihood of survival. Although such behavioural flexibility is regularly observed in the field, it has proven difficult to systematically quantify and predict inter-individual differences in free-living animals. We presented 24 Zenaida doves (Zenaida aurita) on 12 territories with two learning tests in their natural habitat in Barbados. The dove pairs showed high site fidelity and territoriality, allowing us to test individuals repeatedly while accounting for the effects of territorial chases and pair bonds on our learning measures. We used a foraging apparatus that enabled Zenaida doves to access seed, yet excluded other species, and measured doves' performance on colour discrimination and reversal learning tests. We found that (1) doves on all 12 territories passed the two tests; (2) mates within a pair were consistently solvers or scroungers; (3) sex, body condition and territorial chases did not consistently affect learning rates; (4) tameness was a significant negative predictor of learning to feed from the foraging apparatus and (5) scrounging within pairs seemed to facilitate learning. Our study presents a method to quantify intraspecific differences in behavioural flexibility in the field and relate these to individuals' physical and social traits. © 2010 Elsevier B.V.
Abstract.
Hoppitt W, Boogert NJ, Laland KN (2010). Detecting social transmission in networks.
Journal of Theoretical Biology,
263(4), 544-555.
Abstract:
Detecting social transmission in networks
In recent years researchers have drawn attention to a need for new methods with which to identify the spread of behavioural innovations through social transmission in animal populations. Network-based analyses seek to recognise diffusions mediated by social learning by detecting a correspondence between patterns of association and the flow of information through groups. Here we introduce a new order of acquisition diffusion analysis (OADA) and develop established time of acquisition diffusion analysis (TADA) methods further. Through simulation we compare the merits of these and other approaches, demonstrating that OADA and TADA have greater power and lower Type I error rates than available alternatives, and specifying when each approach should be deployed. We illustrate the new methods by applying them to reanalyse an established dataset corresponding to the diffusion of foraging innovations in starlings, where OADA and TADA detect social transmission that hitherto had been missed. The methods are potentially widely applicable by researchers wishing to detect social learning in natural and captive populations of animals, and to facilitate this we provide code to implement OADA and TADA in the statistical package R. © 2010 Elsevier Ltd. All rights reserved.
Abstract.
Boogert NJ, Bui C, Howarth K, Giraldeau LA, Lefebvre L (2010). Does foraging behaviour affect female mate preferences and pair formation in captive zebra finches?.
PLoS ONE,
5(12).
Abstract:
Does foraging behaviour affect female mate preferences and pair formation in captive zebra finches?
Background: Successful foraging is essential for survival and reproductive success. In many bird species, foraging is a learned behaviour. To cope with environmental change and survive periods in which regular foods are scarce, the ability to solve novel foraging problems by learning new foraging techniques can be crucial. Although females have been shown to prefer more efficient foragers, the effect of males' foraging techniques on female mate choice has never been studied. We tested whether females would prefer males showing the same learned foraging technique as they had been exposed to as juveniles, or whether females would prefer males that showed a complementary foraging technique. Methodology/Principal Findings: We first trained juvenile male and female zebra finches (Taeniopygia guttata) to obtain a significant proportion of their food by one of two foraging techniques. We then tested whether females showed a preference for males with the same or the alternative technique. We found that neither a male's foraging technique nor his foraging performance affected the time females spent in his proximity in the mate-choice apparatus. We then released flocks of these finches into an aviary to investigate whether assortative pairing would be facilitated by birds taught the same technique exploiting the same habitat. Zebra finches trained as juveniles in a specific foraging technique maintained their foraging specialisation in the aviary as adults. However, pair formation and nest location were random with regard to foraging technique. Conclusions/Significance: Our findings show that zebra finches can be successfully trained to be foraging specialists. However, the robust negative results of the conditions tested here suggest that learned foraging specializations do not affect mate choice or pair formation in our experimental context. © 2010 Boogert et al.
Abstract.
Laland KN, Boogert NJ (2010). Niche construction, co-evolution and biodiversity.
Ecological Economics,
69(4), 731-736.
Abstract:
Niche construction, co-evolution and biodiversity
Many organisms modulate the availability of resources to other species, in the process changing the selection to which they and other organisms are exposed (niche construction). Niche construction drives co-evolutionary episodes, and builds connectance between the biotic components of ecosystems. Organisms have significant non-trophic impacts on ecosystem structure, function, and biodiversity. Based on a review of the most recent literature, we propose measures that could be employed to manage environments and enhance conservation efforts. © 2008 Elsevier B.V. All rights reserved.
Abstract.
2009
Lefebvre L, Boogert NJ (2009). Avian Social Learning. In (Ed)
Encyclopedia of Animal Behavior, 124-130.
Abstract:
Avian Social Learning
Abstract.
Botero CA, Boogert NJ, Vehrencamp SL, Lovette IJ (2009). Climatic Patterns Predict the Elaboration of Song Displays in Mockingbirds.
Current Biology,
19(13), 1151-1155.
Abstract:
Climatic Patterns Predict the Elaboration of Song Displays in Mockingbirds
Climatic variability and unpredictability [1] affect the distribution and abundance of resources and the timing and duration of breeding opportunities. In vertebrates, climatic variability selects for enhanced cognition when organisms compensate for environmental changes through learning and innovation [2-5]. This hypothesis is supported by larger brain sizes [6], higher foraging innovation rates [7-9], higher reproductive flexibility [10-12], and higher sociality [13] in species living in more variable climates. Male songbirds sing to attract females and repel rivals [14]. Given the reliance of these displays on learning and innovation, we hypothesized that they could also be affected by climatic patterns. Here we show that in the mockingbird family (Aves: Mimidae), species subject to more variable and unpredictable climates have more elaborate song displays. We discuss two potential mechanisms for this result, both of which acknowledge that the complexity of song displays is largely driven by sexual selection [15, 16]. First, stronger selection in more variable and unpredictable climates could lead to the elaboration of signals of quality [14, 17-20]. Alternatively, selection for enhanced learning and innovation in more variable and unpredictable climates might lead to the evolution of signals of intelligence in the context of mate attraction [14, 21-23]. © 2009 Elsevier Ltd. All rights reserved.
Abstract.
Overington SE, Morand-Ferron J, Boogert NJ, Lefebvre L (2009). Technical innovations drive the relationship between innovativeness and residual brain size in birds.
Animal Behaviour,
78(4), 1001-1010.
Abstract:
Technical innovations drive the relationship between innovativeness and residual brain size in birds
The hypothesis that large brains allow animals to produce novel behaviour patterns is supported by the correlation between brain size, corrected for body size, and the frequency of foraging innovations reported in the literature for both birds and primates. In birds, foraging innovations have been observed in over 800 species, and include behaviours that range from eating a novel food to using tools. Previous comparative studies have quantified innovativeness by summing all reports of innovative behaviour, regardless of the nature of the innovation. Here, we use the variety of foraging innovations recorded for birds to see which of two classic hypotheses best accounts for the relationship between innovativeness and brain size: the technical intelligence hypothesis or the opportunistic-generalism intelligence hypothesis. We classified 2182 innovation cases into 12 categories to quantify the diversity of innovations performed by each of 76 avian families. We found that families with larger brains had a greater repertoire of innovations, and that innovation diversity was a stronger predictor of residual brain size than was total number of innovations. Furthermore, the diversity of technical innovations displayed by bird families was a much better predictor of residual brain size than was the number of food type innovations, providing support for the technical intelligence hypothesis. Our results suggest that the cognitive capacity required to perform a wide variety of novel foraging techniques underpins the positive relationship between innovativeness and brain size in birds. We include a summary of innovation data for 803 species as Supplementary Material. © 2009 the Association for the Study of Animal Behaviour.
Abstract.
2008
Boogert NJ, Giraldeau LA, Lefebvre L (2008). Song complexity correlates with learning ability in zebra finch males.
Animal Behaviour,
76(5), 1735-1741.
Abstract:
Song complexity correlates with learning ability in zebra finch males
In species with mate choice, the choosy sex selects its mate based on traits that are thought to indicate the mate's quality. In several bird species, females prefer males that sing more complex songs but it is unclear which aspect of male quality is signalled by this trait. Here we tested the hypothesis that a male's song complexity conveys information about his learning capacity. We recorded the songs of 27 male zebra finches, Taeniopygia guttata, and quantified their complexity by measuring average song phrase duration, the total number of elements and the number of unique elements per song phrase. We then presented each male with a novel foraging task and recorded the number of trials he required to solve the task. We found a positive correlation between song complexity and learning proficiency: males with more song phrase elements required fewer learning trials to solve the novel foraging task. This result suggests that a male's song complexity signals his learning ability, which may have contributed to the selective pressures driving females to choose males with more complex songs. © 2008 the Association for the Study of Animal Behaviour.
Abstract.
Boogert NJ, Reader SM, Hoppitt W, Laland KN (2008). The origin and spread of innovations in starlings.
Animal Behaviour,
75(4), 1509-1518.
Abstract:
The origin and spread of innovations in starlings
There are numerous reports of novel learned behaviour patterns in animal populations, yet the factors influencing the invention and spread of these innovations remain poorly understood. Here we investigated to what extent the pattern of spread of innovations in captive groups of starlings, Sturnus vulgaris, could be predicted by knowledge of individual and social group variables, including association patterns, social rank orders, measures of neophobia and asocial learning performance. We presented small groups of starlings with a series of novel extractive foraging tasks and recorded the latency for each bird to contact and solve each task, as well as the orders of contacting and solving. We then explored which variables best predicted the observed diffusion patterns. Object neophobia and social rank measures characterized who was the first of the group to contact the novel foraging tasks, and the subsequent spread of contacting tasks was associated with latency to feed in a novel environment. Asocial learning performance, measured in isolation, predicted who was the first solver of the novel foraging tasks in each group. Association patterns did not predict the spread of solving. Contact latency and solving duration were negatively correlated, consistent with social learning underlying the spread of solving. Our findings indicate that we can improve our understanding of the diffusion dynamics of innovations in animal groups by investigating group-dependent and individual variables in combination. We introduce novel methods for exploring predictors of the origin and spread of behavioural innovations that could be widely applied. © 2008 the Association for the Study of Animal Behaviour.
Abstract.
2006
Boogert NJ, Paterson DM, Laland KN (2006). The implications of niche construction and ecosystem engineering for conservation biology.
BioScience,
56(7), 570-578.
Abstract:
The implications of niche construction and ecosystem engineering for conservation biology
Although strategies to conserve biodiversity (e.g. the establishment of reserves and the management of flagship, umbrella, indicator, and keystone species) are valuable, they entail practical and conceptual difficulties. A focus on niche construction and ecosystem engineering, however, could provide new insights and methods for conservation biology. Many organisms modulate the availability of resources to other species by causing state changes in biotic or abiotic materials (ecosystem engineering), in the process frequently changing the selection to which the ecosystem engineers and other organisms are exposed (niche construction). We describe growing evidence that organisms have significant nontrophic impacts on ecosystem structure, function, and biodiversity, and outline established means of identifying key species involved in niche construction. On the basis of this engineering perspective, we propose a number of measures that could be employed to enhance conservation efforts. © 2006 American Institute of Biological Sciences.
Abstract.
Boogert NJ, Reader SM, Laland KN (2006). The relation between social rank, neophobia and individual learning in starlings.
Animal Behaviour,
72(6), 1229-1239.
Abstract:
The relation between social rank, neophobia and individual learning in starlings
Researchers with diverse interests in topics ranging from the formation of dominance hierarchies and social intelligence to animal personalities have predicted specific, and often conflicting, relations between social rank, neophobia and learning ability. We investigated the relations between these variables in captive groups of wild-caught starlings, Sturnus vulgaris, adopting a multidimensional approach to social rank and neophobia. Both agonistic and competitive rank orders were determined for each group and we tested individuals in the absence of their groupmates for object neophobia, latency to feed in a novel environment and performance on an extractive foraging task. In each starling group, the fastest learners occupied the highest competitive ranks, supporting the hypothesis that cognitive ability is positively correlated with social dominance. Competitive rank orders, however, did not correlate significantly with agonistic rank orders. Situation-specific foraging neophobia was suggested: individuals showed consistency in their latencies to feed near a variety of novel objects, but no significant correlation was found between this measure of object neophobia and latency to feed in a novel environment. Starlings fastest to feed in the novel environment were fastest in solving the foraging task. We discuss the implications of these findings for researchers studying hierarchy formation in animal groups, social intelligence and animal personalities. © 2006 the Association for the Study of Animal Behaviour.
Abstract.
Boogert NJ, Hofstede FE, Aguilar Monge I (2006). The use of food source scent marks by the stingless bee Trigona corvina (Hymenoptera: Apidae): the importance of the depositor's identity.
Apidologie,
37(3), 366-375.
Abstract:
The use of food source scent marks by the stingless bee Trigona corvina (Hymenoptera: Apidae): the importance of the depositor's identity
The deposition and use of scent marks on food sources has been found in foraging solitary bees, bumblebees, stingless bees and honeybees. The widespread existence of this communication mechanism points to its ecological significance. The importance of the depositor's identity on the use of food source scent marks, however, has never been systematically investigated in the same bee species. Here we present strong evidence that individual foragers of the stingless bee species Trigona corvina scent marked a high quality food source and that they used their own scent marks to relocate it in choice experiments. T. corvina foragers showed a similar significant preference for a food source scent marked by their nest mates and by bees from a conspecific colony over a non-scent marked food source. However, no evidence for the use of scent marks deposited by other stingless bee species was found. The implications of these findings for the evolution of food source scent marking in bees are discussed. © INRA/DIB-AGIB/ EDP Sciences, 2006.
Abstract.
