Operant conditioning in antlion larvae and its impairment following exposure to elevated temperatures

Animal Cognition - Although ambush predators were previously considered limited in their cognitive abilities compared to their widely foraging relatives, there is accumulating evidence it does not...     

The Limitations of Heuristics for Political Elites

Despite the extensive literature on citizens' use of cognitive heuristics in political settings, far less is known about how political elites use these shortcuts. Legislative elites benefit from the efficiency of the accessibility heuristic, but their judgments can also be flawed if accessible information is incomplete or unrepresentative. Using personal interviews and a quasi-experimental design, this paper examines the use of the accessibility heuristic by professional legislative staff when assessing the importance of natural resources issues to their constituents. Staff members recall only a small subset of the relevant constituents in the district, and this subset is biased in favor of active and resource-rich constituents over other, equally relevant constituents. This paper provides a new application of cognitive psychology to political elites and addresses important normative questions about the importance of information processing for political representation. By drawing on the psychology literature on heuristics, this paper identifies the cognitive mechanisms of congressional representation and provides new evidence of old biases.     

Doomed to repeat the successes of the past: History is best forgotten for repeated choices with nonstationary payoffs

Many everyday tasks involve repeated choices in which past outcomes are used to estimate payoffs but in which present payoffs may differ from past ones. Two experiments with 10 decision problems employing the decisions-from-feedback paradigm examined the choice between two risky options, wherein the payoff probabilities for one option could change over a sequence of trials. Participants either saw the outcomes associated with each option, or additionally were given a “history” summarizing the outcomes of previous trials. Participants adapted quickly to new problems, but adapted slowly to payoff changes. Providing a history improved initial choices, but had a null or negative impact on later ones—although, appropriately, the summary received less weight in later trials. An associative choice model captured changes in preference, but not initial patterns of choice. The findings emphasize the adaptive value of forgetting in unstable decision environments, but illustrate how providing additional relevant information may hinder this.     

Sedentary antlion larvae (Neuroptera: Myrmeleontidae) use vibrational cues to modify their foraging strategies

Learning abilities are exhibited by many animals, including insects. However, sedentary species are typically believed to have low capacities and requirements for learning. Despite this view, recent studies show that even such inconspicuous organisms as larval antlions, which employ an ambush predation strategy, are capable of learning, although their learning abilities are rather simple, i.e., limited to the association of vibrational cues with the arrival of prey. This study demonstrates, for the first time, that antlion larvae can use vibrational cues for complex modifications of their foraging strategies. Specifically, antlion larvae rapidly learn to differentiate between the vibrational cues associated with prey of different sizes, and they save resources by ignoring smaller prey in favour of larger, more energetically profitable prey. Moreover, antlion larvae can learn to associate vibrational cues with the loss of their prey, and they respond by burying their victims under the sand more often and more rapidly than do individuals with no opportunities to form such associations. These findings provide not only new insights into the cognitive abilities of animals but also support for the optimal foraging strategy concept, suggesting the importance of maximizing fitness output by balancing the costs and benefits of alternative foraging strategies.     

Larval antlions show a cognitive ability/hunting efficiency trade-off connected with the level of behavioural asymmetry

Recently, antlion larvae with greater behavioural asymmetry were shown to have improved learning abilities. However, a major evolutionary question that remained unanswered was why this asymmetry does not increase in all individuals during development. Here, we show that a trade-off exists between learning ability of larvae and their hunting efficiency. Larvae with greater asymmetry learn better than those with less, but the latter are better able to sense vibrational signals used to detect prey and can capture prey more quickly. Both traits, learning ability and hunting efficiency, present obvious fitness advantages; the trade-off between them may explain why behavioural asymmetry, which presumably stems from brain lateralization, is relatively rare in natural antlion populations.     

Injury shortens life expectancy in ants and affects some risk-related decisions of workers

Animal Cognition - The Formica cinerea ants are known to be highly territorial and aggressively defend their nest and foraging areas against other ants. During the foraging, workers engage in...