Monoamines and decision making during contests in the hermit crab Pagurus bernhardus

During fights animals are expected to make a series of strategic decisions that involve interactions between information about the contest and the individual's nervous system that produce a change in behaviour. Biogenic monoamines such as serotonin ('5-HT') and dopamine are thought to prime decision-making centres for appropriate responses during aggressive interactions in crustaceans, and circulating levels vary both between individuals and during agonistic encounters. Aminergenic systems operate in diverse animal taxa and in this study we assayed circulating levels of S-HT and dopamine following shell fights in the common European hermit crab, Pagurus bernhardus. The two roles in these fights, attacker and defender, perform different activities but, in both, S-HT increased and dopamine declined in response to engaging in a fight. In defenders but not attackers, giving up was correlated with low 5-HT and dopamine. In attackers, motivation to initiate a fight was positively correlated with dopamine levels. Circulating monoamines are therefore involved in decision making during these aggressive encounters. (c) 2007 The Association for the Study of Animal Behaviour Published by Elsevier Ltd. All rights reserved.

Information gathering and decision making about resource value in animal contests

Contestants are predicted to adjust the cost of a fight in line with the perceived value of the resource and this provides a way of determining whether the resource has been assessed. An assessment of resource value is predicted to alter an animal's motivational state and we note different methods of measuring that state. We provide a categorical framework in which the degree of resource assessment may be evaluated and also note limitations of various approaches. We place studies in six categories: (1) cases of no assessment, (2) cases of internal state such as hunger influencing apparent value, (3) cases of the contestants differing in assessment ability, (4) cases of mutual and equal assessment of value, (5) cases where opponents differ in resource value and (6) cases of particularly complex assessment abilities that involve a comparison of the value of two resources. We examine the extent to which these studies support game theory predictions and suggest future areas of research. (C) 2008 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

Adolescent men's attitudes and decision-making in relation to an unplanned pregnancy. Responses to an interactive video drama

This study confronts a gender bias in research on adolescent pregnancy by exploring adolescent men’s decisions relating to a hypothetical unplanned pregnancy. A cross-sectional survey was conducted with adolescent men (N = 360) aged between 14 and 18 years attending schools in the Republic of Ireland. The study, the first of its kind in Europe, extends the small body of evidence on adolescent men and pregnancy decision-making by developing and examining reactions to an interactive video drama used in a comparable study in Australia. In addition, we tested a more comprehensive range of sociological and psychological determinants of adolescent men’s decisions regarding an unplanned pregnancy. Results showed that adolescent men were more likely to choose to keep the baby in preference to abortion or adoption. Adolescent men’s choice to continue the pregnancy (keep or adopt) in preference to abortion was significantly associated with anticipated feelings of regret in relation to abortion, perceived positive attitudes of own mother to keeping the baby and a feeling that a part of them might want a baby. Religiosity was also shown to underlie adolescent men’s views on the perceived consequences of an abortion in their lives.

Getting priorities straight: Risk assessment and decision-making in the improvement of inherited disorders in pedigree dogs

The issue of inherited disorders in pedigree dogs is not a recent phenomenon and reports of suspected genetic defects associated with breeding practices date back to Charles Darwin's time. In recent years, much information on the array of inherited defects has been assimilated and the true extent of the problem has come to light. Historically, the direction of research funding in the field of canine genetic disease has been largely influenced by the potential transferability of findings to human medicine, economic benefit and importance of dogs for working purposes. More recently, the argument for a more canine welfare-orientated approach has been made, targeting research efforts at the alleviation of the most suffering in the greatest number of animals.