Ecology and Evolutionary Biology Commons^™

Ontogenetic Shifts In The Costs Of Living In Groups: Focal Observations Of A Pholcid Spider (Holocnemus Pluchei), Elizabeth Jakob, Julie Blanchong, Mary Popson, Kristine Sedey, Michael Summerfield

Psychological and Brain Sciences Faculty Publication Series

Holocnemus pluchei spiders (Family Pholcidae) facultatively live in groups: sometimes they live alone and sometimes they share webs. In the field groups vary in size and composition and include spiders of all ages and either sex. Group membership is flexible and individuals move frequently among groups. To understand group formation and maintenance it is necessary to understand the costs of group membership. We used focal animal sampling to investigate the cost of group living for spiders of different ages across a range of group sizes. Both spider age and group size affected the costs incurred by group-living spiders. There was …