Individual differences in behaviour explain variation in survival: a meta-analysis

Research focusing on among-individual differences in behaviour (“animal personality”) has been blooming for over a decade. One of the central theories explaining the maintenance of behavioural variation posits a trade-off between behaviour and survival with individuals expressing greater “risky” behaviours suffering higher mortality. Here, for the first time, we synthesize the existing empirical evidence for this key prediction. Our results did not support this prediction as there was no directional relationship between riskier behaviour and greater mortality; however there was a significant absolute relationship between behaviour and survival. In total, behaviour explained a significant, but small, portion (4.4%) of the variance in survival. We also found that risky (versus “shy”) behavioural types live longer in the wild, but not in the laboratory. This suggests that individuals expressing risky behaviours might be of overall higher quality but the lack of predation pressure and resource restrictions mask this effect in laboratory environments. Our work implies that individual differences in behaviour explain important differences in survival but not in the direction predicted by theory. Importantly, this suggests that the models predicting survival trade-offs may need revision and/or empiricists may need to reconsider their proxies of risky behaviours when testing such theory.

Download Full-text

Evolutionary causes and consequences of consistent individual variation in cooperative behaviour

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2010.0124 ◽

2010 ◽

Vol 365 (1553) ◽

pp. 2751-2764 ◽

Cited By ~ 77

Author(s):

Ralph Bergmüller ◽

Roger Schürch ◽

Ian M. Hamilton

Keyword(s):

Individual Differences ◽

Empirical Evidence ◽

Individual Variation ◽

Animal Personality ◽

Evolutionary Stability ◽

Behavioural Syndrome ◽

Phenotypic Traits ◽

Cooperative Behaviour ◽

Heritable Variation ◽

Fitness Consequences

Behaviour is typically regarded as among the most flexible of animal phenotypic traits. In particular, expression of cooperative behaviour is often assumed to be conditional upon the behaviours of others. This flexibility is a key component of many hypothesized mechanisms favouring the evolution of cooperative behaviour. However, evidence shows that cooperative behaviours are often less flexible than expected and that, in many species, individuals show consistent differences in the amount and type of cooperative and non-cooperative behaviours displayed. This phenomenon is known as ‘animal personality’ or a ‘behavioural syndrome’. Animal personality is evolutionarily relevant, as it typically shows heritable variation and can entail fitness consequences, and hence, is subject to evolutionary change. Here, we review the empirical evidence for individual variation in cooperative behaviour across taxa, we examine the evolutionary processes that have been invoked to explain the existence of individual variation in cooperative behaviour and we discuss the consequences of consistent individual differences on the evolutionary stability of cooperation. We highlight that consistent individual variation in cooperativeness can both stabilize or disrupt cooperation in populations. We conclude that recognizing the existence of consistent individual differences in cooperativeness is essential for an understanding of the evolution and prevalence of cooperation.

Download Full-text

Linking behavioural syndromes and cognition: a behavioural ecology perspective

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2012.0216 ◽

2012 ◽

Vol 367 (1603) ◽

pp. 2762-2772 ◽

Cited By ~ 308

Author(s):

Andrew Sih ◽

Marco Del Giudice

Keyword(s):

Decision Making ◽

Individual Differences ◽

Behavioural Ecology ◽

Risk Sensitivity ◽

Model Species ◽

Behavioural Syndromes ◽

Trade Offs ◽

Behavioural Types ◽

Cognitive Speed ◽

Speed Accuracy

With the exception of a few model species, individual differences in cognition remain relatively unstudied in non-human animals. One intriguing possibility is that variation in cognition is functionally related to variation in personality. Here, we review some examples and present hypotheses on relationships between personality (or behavioural syndromes) and individual differences in cognitive style. Our hypotheses are based largely on a connection between fast–slow behavioural types (BTs; e.g. boldness, aggressiveness, exploration tendency) and cognitive speed–accuracy trade-offs. We also discuss connections between BTs, cognition and ecologically important aspects of decision-making, including sampling, impulsivity, risk sensitivity and choosiness. Finally, we introduce the notion of cognition syndromes, and apply ideas from theories on adaptive behavioural syndromes to generate predictions on cognition syndromes.

Download Full-text

Are nest defense behaviours and fitness components linked in white-rumped swallows (Tachycineta leucorrhoa)?

Behaviour ◽

10.1163/1568539x-00003535 ◽

2019 ◽

Vol 156 (2) ◽

pp. 181-201

Author(s):

Uschi Wischhoff ◽

Fernando Marques-Santos ◽

Giselle Bonetti ◽

Lilian T. Manica ◽

James J. Roper ◽

...

Keyword(s):

Wild Animal ◽

Nest Defence ◽

Costs And Benefits ◽

Fitness Components ◽

Trade Off ◽

Trade Offs ◽

Animal Populations ◽

Behavioural Types ◽

One Year ◽

Different Levels

Abstract How are personalities maintained in wild animal populations? A possible mechanism is the existence of trade-offs between fitness components (survival and reproductive success) among behavioural types. We investigated this trade-off in white-rumped swallows (Tachycineta leucorrhoa) by capturing adults and monitoring their reproduction over time. We focused on the personality trait of nest defence against a human. We found that swallows with different levels of nest defence had similar probability to return from migration between two years (a proxy for survival). In one year, swallows that defended their nests more boldly were also more likely to succeed. However, nest defence was not linked to nestling weight or number of fledglings. Thus, we found no evidence of a trade-off between fitness components. It is possible that the investigated relationships become relevant only in extreme years that severely alter the costs and benefits of this behaviour.

Download Full-text

Sex and boldness explain individual differences in spatial learning in a lizard

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.3275 ◽

2014 ◽

Vol 281 (1782) ◽

pp. 20133275 ◽

Cited By ~ 64

Author(s):

Pau Carazo ◽

Daniel W. A. Noble ◽

Dani Chandrasoma ◽

Martin J. Whiting

Keyword(s):

Individual Differences ◽

Cognitive Performance ◽

Spatial Learning ◽

Environmental Variability ◽

Learning Task ◽

Spatial Task ◽

Individual Variability ◽

Biologically Relevant ◽

Trade Offs ◽

Behavioural Types

Understanding individual differences in cognitive performance is a major challenge to animal behaviour and cognition studies. We used the Eastern water skink ( Eulamprus quoyii ) to examine associations between exploration, boldness and individual variability in spatial learning, a dimension of lizard cognition with important bearing on fitness. We show that males perform better than females in a biologically relevant spatial learning task. This is the first evidence for sex differences in learning in a reptile, and we argue that it is probably owing to sex-specific selective pressures that may be widespread in lizards. Across the sexes, we found a clear association between boldness after a simulated predatory attack and the probability of learning the spatial task. In contrast to previous studies, we found a nonlinear association between boldness and learning: both ‘bold’ and ‘shy’ behavioural types were more successful learners than intermediate males. Our results do not fit with recent predictions suggesting that individual differences in learning may be linked with behavioural types via high–low-risk/reward trade-offs. We suggest the possibility that differences in spatial cognitive performance may arise in lizards as a consequence of the distinct environmental variability and complexity experienced by individuals as a result of their sex and social tactics.

Download Full-text

Repeatability of decision-making behaviour in male threespine stickleback Gasterosteus aculeatus: Effects of dummy vs. live stimuli

Current Zoology ◽

10.1093/czoolo/57.1.101 ◽

2011 ◽

Vol 57 (1) ◽

pp. 101-108 ◽

Cited By ~ 1

Author(s):

Teresa L. Dzieweczynski ◽

Lindsay M. Forrette

Keyword(s):

Decision Making ◽

Individual Differences ◽

Gasterosteus Aculeatus ◽

Threespine Stickleback ◽

Costs And Benefits ◽

Male And Female ◽

Trade Off ◽

Trade Offs ◽

Consistent Manner ◽

Males And Females

Abstract Individuals select from a number of behaviours when responding to various situations and the decisions they make may affect their fitness. The costs and benefits of these responses vary among individuals causing them to differ even in identical situations. One example of this type of situation is when territorial males encounter both a male and female simultaneously, generating a trade-off that likely leads to individual differences due to differing costs of various actions among males. This situation commonly occurs in threespine stickleback, Gasterosteus aculeatus. However, for selection to act effectively, individuals must behave in a consistent manner and measuring repeatability can aid in understanding how selection may shape such trade-offs. Males of this species exhibit consistent individual differences in their response to dummy males and females but it is unknown if patterns are similar when feedback from the stimuli is present. To assess this, male threespine stickleback were tested with dummy and live male and female conspecifics, presented separately and simultaneously. While the same trends were found regardless of stimulus type, males were more aggressive towards the live conspecifics than to the dummies. Repeatability values were similar within a treatment regardless of whether live or dummy conspecifics were used, suggesting that individuals show the same level of consistency. This study adds to our understanding of consistent individual differences by demonstrating that feedback may not affect responses to conflicting stimuli and that male threespine stickleback respond in a consistent manner to both dummy and live stimuli.

Download Full-text

Dual Goals for Speed and Accuracy on the Same Performance Task

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000063 ◽

2012 ◽

Vol 11 (3) ◽

pp. 118-126 ◽

Cited By ~ 3

Author(s):

Olive Emil Wetter ◽

Jürgen Wegge ◽

Klaus Jonas ◽

Klaus-Helmut Schmidt

Keyword(s):

Memory Scanning ◽

Performance Task ◽

Performance Tasks ◽

Trade Off ◽

Test Experiment ◽

Trade Offs ◽

New Finding ◽

Sternberg Paradigm ◽

Speed Accuracy ◽

Speed And Accuracy

In most work contexts, several performance goals coexist, and conflicts between them and trade-offs can occur. Our paper is the first to contrast a dual goal for speed and accuracy with a single goal for speed on the same task. The Sternberg paradigm (Experiment 1, n = 57) and the d2 test (Experiment 2, n = 19) were used as performance tasks. Speed measures and errors revealed in both experiments that dual as well as single goals increase performance by enhancing memory scanning. However, the single speed goal triggered a speed-accuracy trade-off, favoring speed over accuracy, whereas this was not the case with the dual goal. In difficult trials, dual goals slowed down scanning processes again so that errors could be prevented. This new finding is particularly relevant for security domains, where both aspects have to be managed simultaneously.

Download Full-text

An Epistemological Criticism of Social Entrepreneurship: Is Social Entrepreneurship a Sound Scientific Field of Research

10.31124/advance.7091927.v1 ◽

2018 ◽

Author(s):

Amir Forouharfar

Keyword(s):

Social Entrepreneurship ◽

Social Constructivism ◽

Social Epistemology ◽

American English ◽

Meta Analysis ◽

Research Question ◽

Knowledge Structure ◽

Scientific Field ◽

The Other ◽

First Time

The paper was shaped around the pivotal question: Is SE a sound and scientific field of research? The question has given a critical tone to the paper and has also helped to bring out some of the controversial debates in the realm of SE. The paper was organized under five main discussions to be able to provide a scientific answer to the research question: (1) is “social entrepreneurship” an oxymoron?, (2) the characteristics of SE knowledge, (3) sources of social entrepreneurship knowledge, (4) SE knowledge: structure and limitations and (5) contributing epistemology-making concepts for SE. Based on the sections, the study relied on the relevant philosophical schools of thought in Epistemology (e.g. Empiricism, Rationalism, Skepticism, Internalism vs. Externalism, Essentialism, Social Constructivism, Social Epistemology, etc.) to discuss these controversies around SE and proposes some solutions by reviewing SE literature. Also, to determine the governing linguistic discourse in the realm of SE, which was necessary for our discussion, Corpus of Contemporary American English (COCA) for the first time in SE studies was used. Further, through the study, SE buzzwords which constitute SE terminology were derived and introduced to help us narrowing down and converging the thoughts in this field and demarking the epistemological boundaries of SE. The originality of the paper on one hand lies in its pioneering discussions on SE epistemology and on the other hand in paving the way for a construction of sound epistemology for SE; therefore in many cases after preparing the philosophical ground for the discussions, it went beyond the prevalent SE literature through meta-analysis to discuss the cases which were raised. The results of the study verified previously claimed embryonic pre-paradigmatic phase in SE which was far from a sound and scientific knowledge, although the scholarly endeavors are the harbingers of such a possibility in the future which calls for further mature academic discussion and development of SE knowledge by the SE academia.

Download Full-text

The Effects of Decision Time on Perceptions of Decisions and Decision Makers in (Moral) Trade-Off Scenarios

10.31234/osf.io/37t2r ◽

2019 ◽

Author(s):

Anna Katharina Spälti ◽

Mark John Brandt ◽

Marcel Zeelenberg

Keyword(s):

Decision Process ◽

Decision Time ◽

Decision Makers ◽

Process Information ◽

Total N ◽

Trade Off ◽

Financial Gain ◽

Trade Offs ◽

Sacred Values ◽

Moral Context

People often have to make trade-offs. We study three types of trade-offs: 1) "secular trade-offs" where no moral or sacred values are at stake, 2) "taboo trade-offs" where sacred values are pitted against financial gain, and 3) "tragic trade-offs" where sacred values are pitted against other sacred values. Previous research (Critcher et al., 2011; Tetlock et al., 2000) demonstrated that tragic and taboo trade-offs are not only evaluated by their outcomes, but are also evaluated based on the time it took to make the choice. We investigate two outstanding questions: 1) whether the effect of decision time differs for evaluations of decisions compared to decision makers and 2) whether moral contexts are unique in their ability to influence character evaluations through decision process information. In two experiments (total N = 1434) we find that decision time affects character evaluations, but not evaluations of the decision itself. There were no significant differences between tragic trade-offs and secular trade-offs, suggesting that the decisions structure may be more important in evaluations than moral context. Additionally, the magnitude of the effect of decision time shows us that decision time, may be of less practical use than expected. We thus urge, to take a closer examination of the processes underlying decision time and its perception.

Download Full-text

Predicting Undesired Treatment Outcome in Mental Healthcare: Machine Learning Study (Preprint)

10.2196/preprints.17235 ◽

2019 ◽

Author(s):

Kasper Van Mens ◽

Joran Lokkerbol ◽

Richard Janssen ◽

Robert de Lange ◽

Bea Tiemens

Keyword(s):

Machine Learning ◽

Treatment Outcome ◽

Mental Health Treatment ◽

Mental Healthcare ◽

Machine Learning Algorithms ◽

Gradient Boosting ◽

Trade Off ◽

Trade Offs ◽

Outcome Monitoring ◽

Extreme Gradient Boosting

BACKGROUND It remains a challenge to predict which treatment will work for which patient in mental healthcare. OBJECTIVE In this study we compare machine algorithms to predict during treatment which patients will not benefit from brief mental health treatment and present trade-offs that must be considered before an algorithm can be used in clinical practice. METHODS Using an anonymized dataset containing routine outcome monitoring data from a mental healthcare organization in the Netherlands (n = 2,655), we applied three machine learning algorithms to predict treatment outcome. The algorithms were internally validated with cross-validation on a training sample (n = 1,860) and externally validated on an unseen test sample (n = 795). RESULTS The performance of the three algorithms did not significantly differ on the test set. With a default classification cut-off at 0.5 predicted probability, the extreme gradient boosting algorithm showed the highest positive predictive value (ppv) of 0.71(0.61 – 0.77) with a sensitivity of 0.35 (0.29 – 0.41) and area under the curve of 0.78. A trade-off can be made between ppv and sensitivity by choosing different cut-off probabilities. With a cut-off at 0.63, the ppv increased to 0.87 and the sensitivity dropped to 0.17. With a cut-off of at 0.38, the ppv decreased to 0.61 and the sensitivity increased to 0.57. CONCLUSIONS Machine learning can be used to predict treatment outcomes based on routine monitoring data.This allows practitioners to choose their own trade-off between being selective and more certain versus inclusive and less certain.

Download Full-text

Challenges in the Empirical Study of Global Governance Legitimacy

10.1093/oso/9780198826873.003.0011 ◽

2018 ◽

Cited By ~ 1

Author(s):

Steven Bernstein

Keyword(s):

Empirical Study ◽

Global Governance ◽

Research Agenda ◽

Cultural Factors ◽

Theory Building ◽

Trade Off ◽

Trade Offs ◽

Different Types ◽

Political Communities

This commentary discusses three challenges for the promising and ambitious research agenda outlined in the volume. First, it interrogates the volume’s attempts to differentiate political communities of legitimation, which may vary widely in composition, power, and relevance across institutions and geographies, with important implications not only for who matters, but also for what gets legitimated, and with what consequences. Second, it examines avenues to overcome possible trade-offs from gains in empirical tractability achieved through the volume’s focus on actor beliefs and strategies. One such trade-off is less attention to evolving norms and cultural factors that may underpin actors’ expectations about what legitimacy requires. Third, it addresses the challenge of theory building that can link legitimacy sources, (de)legitimation practices, audiences, and consequences of legitimacy across different types of institutions.

Download Full-text