title: Social familiarity reduces reaction times and enhances survival of group-living predatory mites under the risk of predation.
abstract: BACKGROUND
  Social familiarity, which is based on the ability to recognise familiar conspecific individuals following prior association, may affect all major life activities of group-living animals such as foraging, reproduction and anti-predator behaviours. A scarcely experimentally tested explanation why social familiarity is beneficial for group-living animals is provided by limited attention theory. Limited attention theory postulates that focusing on a given task, such as inspection and assessment of unfamiliar group members, has cognitive and associated physiological and behavioural costs with respect to the attention paid to other tasks, such as anti-predator vigilance and response. Accordingly, we hypothesised that social familiarity enhances the anti-predator success of group-living predatory mites, Phytoseiulus persimilis, confronted with an intraguild predator, the predatory mite Amblyseius andersoni.
  
  
  RESULTS
  We videotaped and analysed the response of two P. persimilis larvae, held in familiar or unfamiliar pairs, to attacks by a gravid A. andersoni female, using the behavioural analyses software EthoVision Pro®. Familiar larvae were more frequently close together, reacted more quickly to predator attacks, survived more predator encounters and survived longer than unfamiliar larvae.
  
  
  CONCLUSIONS
  In line with the predictions of limited attention theory, we suggest that social familiarity improves anti-predator behaviours because it allows prey to shift attention to other tasks rather than group member assessment.
authors.affiliation: Group of Arthropod Ecology and Behavior, Division of Plant Protection, Department of Crop Sciences, University of Natural Resources and Life Sciences, Vienna, Austria. markus.strodl@boku.ac.at
authors.forename: Markus Andreas
authors.initials: MA
authors.lastname: Strodl
authors.forename: Peter
authors.initials: P
authors.lastname: Schausberger
mesh_terms: D000818:Animals; D005260:Female; D007814:Larva / Q000502:physiology; D008925:Mites / Q000502:physiology*; D011235:Predatory Behavior / Q000502:physiology*; D011930:Reaction Time; D012306:Risk; D012919:Social Behavior; D016019:Survival Analysis