Antipredator Defences in Sticklebacks: Trade-Offs, Risk Sensitivity, and Behavioural Syndromes

2012 ◽  
Vol 367 (1603) ◽  
pp. 2762-2772 ◽  
Author(s):  
Andrew Sih ◽  
Marco Del Giudice

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.


2011 ◽  
Vol 105 (6) ◽  
pp. 2668-2674 ◽  
Author(s):  
Arne J. Nagengast ◽  
Daniel A. Braun ◽  
Daniel M. Wolpert

When a racing driver steers a car around a sharp bend, there is a trade-off between speed and accuracy, in that high speed can lead to a skid whereas a low speed increases lap time, both of which can adversely affect the driver's payoff function. While speed-accuracy trade-offs have been studied extensively, their susceptibility to risk sensitivity is much less understood, since most theories of motor control are risk neutral with respect to payoff, i.e., they only consider mean payoffs and ignore payoff variability. Here we investigate how individual risk attitudes impact a motor task that involves such a speed-accuracy trade-off. We designed an experiment where a target had to be hit and the reward (given in points) increased as a function of both subjects' endpoint accuracy and endpoint velocity. As faster movements lead to poorer endpoint accuracy, the variance of the reward increased for higher velocities. We tested subjects on two reward conditions that had the same mean reward but differed in the variance of the reward. A risk-neutral account predicts that subjects should only maximize the mean reward and hence perform identically in the two conditions. In contrast, we found that some (risk-averse) subjects chose to move with lower velocities and other (risk-seeking) subjects with higher velocities in the condition with higher reward variance (risk). This behavior is suboptimal with regard to maximizing the mean number of points but is in accordance with a risk-sensitive account of movement selection. Our study suggests that individual risk sensitivity is an important factor in motor tasks with speed-accuracy trade-offs.


2020 ◽  
Vol 98 (11) ◽  
pp. 697-704
Author(s):  
Lawrence M. Dill ◽  
Alejandro Frid

Variation in the behaviour of individuals or species, particularly their propensity to avoid or approach human observers, their conveyances (e.g., cars), or their proxy devices (e.g., drones) has been recognized as a source of bias in transect counts. However, there has been little attempt to predict the likelihood or magnitude of such biases. Behavioural ecology provides a rich source of theory to develop a general framework for doing so. For example, if animals perceive observers as predators, then the extensive body of research on responses of prey to their predators may be applied to this issue. Here we survey the literature on flight initiation distance (the distance from a predator or disturbance stimulus at which prey flee) for a variety of taxa to suggest which characteristics of the animal, the observer, and the environment may create negatively biased counts. We also consider factors that might cause prey to approach observers, creating positive bias, and discuss when and why motivation for both approach and avoidance might occur simultaneously and how animals may resolve such trade-offs. Finally, we discuss the potential for predicting the extent of the behaviourally mediated biases that may be expected in transect counts and consider ways of dealing with them.


2009 ◽  
Vol 6 (1) ◽  
pp. 18-20 ◽  
Author(s):  
Satoshi Nakayama ◽  
Takahisa Miyatake

Consistent individual differences in correlated behaviours across contexts or situations, that is, behavioural syndromes, have recently been identified as an important factor shaping the evolution of behavioural traits, because of their potential for explaining trade-offs in behavioural responses. We examined a genetic link between abilities to mate and to avoid predation from the viewpoint of two genetically correlated behavioural traits; tonic immobility (TI), which is considered to be an antipredator behaviour, and activity levels in the red flour beetle, Tribolium castaneum . Males derived from two strains artificially selected for divergent durations of TI were used in the present study: the L strain (with longer duration and higher frequency of TI) and the S strain (shorter duration and lower frequency of TI). We found that males of the L strain had higher survival rates in predatory environments than those of the S strain, and lower mating success even in predator-free environments. To our knowledge, this is the first empirical study showing a genetic trade-off between abilities to mate and to avoid predation in relation to behavioural syndromes, using individuals exhibiting different behavioural strategies.


2016 ◽  
Vol 16 (5) ◽  
pp. 436-457
Author(s):  
David Spurrett

There is an enduring tension in thinking about the architecture of systems that select behaviours, including evolved organisms. One line of reasoning supports convergence in control systems and conversion of the values of all options into a common currency, in part because this seems the best or only way of trading off costs and benefits associated with outcomes of varying types. A competing consideration supports parallelism or other forms of fragmentation, because of inefficiencies associated with integration, and suspicion towards general-purpose cognitive systems. In addition, recent neuroscience has given particular attention to the question of how partly independent ‘habit based’ and ‘planning based’ decision-systems might interact. The issues here are, at least in part, a special case of the more general integration versus parallelism tension. This tension provides a useful framework for thinking about the implementation of different kinds of sensitivity to risks of various types, the variety of mechanisms by means of which risk sensitivity might be modulated, and how risk might be traded off against other components of value or disincentive. I describe the tension, briefly survey some of the relevant empirical evidence, and conclude with tentative observations on the topic of risk.


Diversity ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 614
Author(s):  
Francisco Javier Zamora-Camacho

Due to their assumed costs, simultaneous antipredator strategies are expected to face trade-offs, which, however, could be milder in individuals subjected to a more intense predator pressure. In this work, I studied the relationship between locomotion and parotoid glands in the natterjack toad, Epidalea calamita. Specifically, I predicted that individuals with reduced sprint speed would rely more on their chemical defences, having larger and more aposematically coloured parotoid glands. In addition, I expected this trade-off to be more evident in females and toads from pine grove habitats, because, according to previous work, males and toads from agrosystems are under greater predator pressure. However, sprint speed showed no relationship with coloration, but toads with proportionally greater parotoid glands were also proportionally faster. Thus, the costs of these antipredator traits might not be high enough to make them interfere, or the benefits of simultaneous optimisation of sprint speed and parotoid gland size might outweigh the costs of it in some individuals. In any case, habitat and sex did not affect these relationships, so the trends detected are valid across sexes and the habitats studied.


2015 ◽  
Vol 58 ◽  
pp. 83-100 ◽  
Author(s):  
Selena Gimenez-Ibanez ◽  
Marta Boter ◽  
Roberto Solano

Jasmonates (JAs) are essential signalling molecules that co-ordinate the plant response to biotic and abiotic challenges, as well as co-ordinating several developmental processes. Huge progress has been made over the last decade in understanding the components and mechanisms that govern JA perception and signalling. The bioactive form of the hormone, (+)-7-iso-jasmonyl-l-isoleucine (JA-Ile), is perceived by the COI1–JAZ co-receptor complex. JASMONATE ZIM DOMAIN (JAZ) proteins also act as direct repressors of transcriptional activators such as MYC2. In the emerging picture of JA-Ile perception and signalling, COI1 operates as an E3 ubiquitin ligase that upon binding of JA-Ile targets JAZ repressors for degradation by the 26S proteasome, thereby derepressing transcription factors such as MYC2, which in turn activate JA-Ile-dependent transcriptional reprogramming. It is noteworthy that MYCs and different spliced variants of the JAZ proteins are involved in a negative regulatory feedback loop, which suggests a model that rapidly turns the transcriptional JA-Ile responses on and off and thereby avoids a detrimental overactivation of the pathway. This chapter highlights the most recent advances in our understanding of JA-Ile signalling, focusing on the latest repertoire of new targets of JAZ proteins to control different sets of JA-Ile-mediated responses, novel mechanisms of negative regulation of JA-Ile signalling, and hormonal cross-talk at the molecular level that ultimately determines plant adaptability and survival.


2012 ◽  
Vol 11 (3) ◽  
pp. 118-126 ◽  
Author(s):  
Olive Emil Wetter ◽  
Jürgen Wegge ◽  
Klaus Jonas ◽  
Klaus-Helmut Schmidt

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.


2007 ◽  
Vol 62 (9) ◽  
pp. 1073-1074 ◽  
Author(s):  
Kennon M. Sheldon ◽  
Melanie S. Sheldon ◽  
Charles P. Nichols

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