Biological Journal of the Linnean Society, 2007, 91, 475–482. With 5 figures © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 91, 475–482 475 Blackwell Publishing LtdOxford, UKBIJBiological Journal of the Linnean Society0024-4066© 2007 The Linnean Society of London? 2007 91? 475482 Original Article BEHAVIOURAL SYNDROMES IN FIELD CRICKETS R. KORTET and A. HEDRICK *Corresponding author. E-mail: rkortet@cc.jyu.fi A behavioural syndrome in the field cricket Gryllus integer: intrasexual aggression is correlated with activity in a novel environment RAINE KORTET 1,2 * and ANN HEDRICK 3 1 Behaviour, Ecology and Evolution Team (Integrative Ecology Unit), Department of Biological and Environmental Sciences, University of Helsinki, PO Box 65(Viikinkaari 1), FI-00014 University of Helsinki, Finland 2 Section of Ecology, Department of Biology, University of Oulu, PO Box 3000, 90014 University of Oulu, Finland 3 Neurobiology, Physiology and Behaviour, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA Received 27 March 2006; accepted for publication 1 September 2006 Behavioural syndromes, or suites of correlated behaviours across different contexts and situations, have recently drawn attention from evolutionary biologists. In the field cricket Gryllus integer, males are aggressive with one another and fight vigorously over females and territories. We examined whether aggressiveness with other males was correlated with activity in a potentially dangerous context (a novel environment) in laboratory-raised virgin males. Aggressiveness was measured as fighting ability against a weight-matched opponent. First, we measured each cricket’s latency to become active in a novel environment and latency to emerge from a refuge within a novel environment. Next, we determined which of two weight-matched males was more aggressive, by pitting the males together in an agonistic contest and counting the number of fights won by each male. More aggressive males, who won more fights, had shorter latencies to become active when placed in a novel environment and shorter latencies to emerge from a safe refuge. These results suggest that a behavioural syndrome exists in G. integer, in which more aggressive males are also more active in general, and possibly less cautious towards predation risk. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 91, 475–482. ADDITIONAL KEYWORDS: antipredator behaviour – boldness – personality – intrasexual dominance. INTRODUCTION Recent studies support the existence of behavioural syndromes, comprising suites of correlated behaviours across different situations or contexts (Hedrick, 2000; Gosling, 2001; Sih, Kats & Maurer, 2003; Sih et al., 2004b; Sih, Bell & Johnson, 2004a; Carere & Eens, 2005). One of the most familiar behavioural syn- dromes in animals is an aggressiveness/activity syn- drome, in which individuals behave more or less aggressively/are more or less active across many con- texts (Sih et al., 2004a,b). For example, in funnel-web spiders, some individuals are more aggressive with conspecifics than others, attack prey more vigorously, and expose themselves to higher risk of predation because of their ‘bold’ or incautious behaviour in the presence of predators (Hedrick & Riechert, 1989, 1990; Riechert & Hedrick, 1993). Aggressiveness towards conspecifics that is correlated with danger- ously bold or noncautious behaviour under predation risk has been demonstrated in a number of species, including stickleback fish (Huntingford, 1976, 1982; Bell, 2005) and fishing spiders (Johnson & Sih, 2005). The existence of behavioural syndromes may offer an explanation for apparently ‘non-adaptive’ behaviour, such as sexual cannibalism, high levels of activity under predation risk, and hyper-aggressiveness that decreases mating success by startling or driving away potential mates (Sih et al, 2004a; Bell, 2005; Sih & Watters, 2005). Moreover, the persistence of behav- ioural ‘types’ within a species (e.g. ‘bold’ and ‘shy’ indi- viduals) suggests that there can be more than one Downloaded from https://academic.oup.com/biolinnean/article/91/3/475/2701113 by EVES-Escola Valenciana dÉstudis de la Salut user on 09 June 2022