Development is a continuous process during which individuals gain information about their environment and adjust phenotype accordingly. In many natural systems, are particularly sensitive to early life experiences, even in the absence of later constraints on plasticity. Recent models have highlighted how adaptive use can explain age-dependent These assume that phenotypic adjustments either cannot occur simultaneously or completely independent. This assumption not valid context growth, where...

Empirical findings suggest that the mammalian brain has two decision-making systems act at different speeds. We represent faster system using standard signal detection theory. slower (but more accurate) cortical as integration of sensory evidence over time until a certain level confidence is reached. then consider how such should be combined optimally for range information linkage mechanisms. conclude with some performance predictions will hold if our representation realistic.

Animals live in complex environments which predation risk and food availability change over time. To deal with this variability maximize their survival, animals should take into account how long current conditions may persist the possible future they encounter. This affect foraging activity, it vulnerability to across periods of good bad conditions. Here we develop a comprehensive theory optimal allocation that allows for environmental persistence fluctuations as well risk. We show is...

Understanding decisions is the fundamental aim of behavioural sciences. The theory rational choice based on axiomatic principles such as transitivity and independence irrelevant alternatives (IIA). Empirical studies have demonstrated that behaviour humans other animals often seems irrational; there can be a lack in seemingly alter decisions. These violations IIA undermine theory. However, we show an individual maximizing its rate food gain exhibit failure IIA. We caused because current...

Moods can be regarded as fluctuating dispositions to make positive and negative evaluations. Developing an evolutionary approach mood adaptive process, we consider the structure function of such states in guiding behavioural decisions regarding acquisition resources avoidance harm different circumstances. We use a drift diffusion model decision making information required by individuals optimise between two alternatives, whether or withdraw from stimulus that may life enhancing threatening....

Exotic predators can have major negative impacts on prey. Importantly, prey vary considerably in their behavioral responses to exotic predators. Factors proposed explain variation response include the similarity of new familiar, native predators, prevalence and diversity a prey's past, innate ability discriminate between safety. While these factors been put forth verbally literature, no theory exists that combines hypotheses common conceptual framework using unified model. Here, we formalize...

Human activity alters natural habitats for many species. Understanding variation in animals' behavioural responses to these changing environments is critical. We show how signal detection theory can be used within a wider framework of state-dependent modelling predict major environmental change: novel, exotic allow thresholds action function reserves, and demonstrate optimal calculated. term this ‘state-dependent theory’ (SDDT). focus on fitness outcomes when animals continue use formerly...

Many animals respond well behaviorally to stimuli associated with human-induced rapid environmental change (HIREC), such as novel predators or food sources. Yet others make errors and succumb evolutionary traps: approaching even preferring low quality, dangerous toxic options, avoiding beneficial stimuli, wasting resources responding neutral payoffs. A common expectation is that learning should help adjust HIREC; however, not always expected favored in many scenarios expose ecological traps....

ABSTRACT While a large body of research has focused on the physiological effects multiple environmental stressors, how behavioural and life‐history plasticity mediate multiple‐stressor remains underexplored. Behavioural can not only drive organism‐level responses to stressors directly but also responses. Here, we provide conceptual framework incorporating four fundamental trade‐offs that explicitly link animal behaviour life‐history‐based pathways for energy allocation, shaping impact...

Ecology Letters (2011) 14: 58–62 Abstract We propose operational definitions of reproductive optimism and pessimism; involves behaving in a way that gives too much weight (in terms producing surviving offspring) to positive events, pessimism negative events. Natural selection maximizes the long-term growth lineage rather than short-term measures such as numbers offspring. Consequently, or can be favoured by natural selection, even though biases appear irrational from perspective. investigate...

Laboratory studies on a range of animals have identified bias that seems to violate basic principles rational behavior: preference is shown for feeding options previously provided food when reserves were low, even though another option had been found give the same reward with less delay. The presents challenge normative models decision making (which only take account expected rewards and state animal at time). To understand behavior, we broad ecological perspective consider how valuation...

Signal detection theory has influenced the behavioural sciences for over 50 years. The provides a simple equation that indicates numerous 'intuitive' results; e.g. prey should be more prone to take evasive action (in response an ambiguous cue) if predators are common. Here, we use analytical and computational models show that, in biological scenarios, standard results of signal do not apply; can result being less responsive such cues. need apply when probability danger pertains just present,...

Background and objectives: Depression is a major medical problem diagnosed in an increasing proportion of people for which commonly prescribed psychoactive drugs are frequently ineffective. Development treatment options may be facilitated by evolutionary perspective; several adaptive reasons proneness to depression have been proposed. A common feature many explanations that depressive behaviour way avoid costly effort where benefits small and/or unlikely. However, this viewpoint fails...

Decisions made while searching for settlement sites (e.g., nesting, oviposition) often have major fitness implications. Despite numerous case studies, we lack theory to explain why some species are thriving others making poor habitat choices after environmental change. We develop a model predict (1) which kinds of change larger, negative effects on fitness, (2) how evolutionary history affects susceptibility change, and (3) much lost can be recovered via readjustment the common scenario...

Understanding decisions is a fundamental aim of behavioural ecology, psychology and economics. The regularity axiom utility theory holds that preference between options should be maintained when other are made available. Empirical studies have shown animals violate but this has not been understood from theoretical perspective, such therefore labelled as irrational. Here, I use models state-dependent behaviour to demonstrate choices can even strategies optimal. also show the range conditions...