Trait-specific indirect effects underlie variation in the response of spiders to cannibalistic social partners

Organisms may respond in different ways to the risk posed by conspecifics, but the cause of such variation remains elusive. Here, we use a half-sib/full-sib design to evaluate the contribution of (indirect) genetic or environmental effects to the behavioral response of the cannibalistic wolf spider Lycosa fasciiventris (Dufour, 1835) towards conspecific cues. Spiders showed variation in relative occupancy time, activity, and velocity on patches with or without conspecific cues, but direct genetic variance was only found for occupancy time. These three traits were correlated and could be lumped in a principal component: spiders spending more time in patches with conspecific cues moved less and at a lower rate in those areas. Genetic and/or environmental components of carapace width and weight loss in the social partner were significantly correlated with the principal component of focal individuals. Individual Variation in these traits may reflect the quality and/or quantity of cues produ..., Spider collection and rearing conditions
Lycosa fasciiventris individuals (adult males and subadult females) were collected between June and July 2015 in four different localities within the Almeria province (South-East Spain), in dry temporal washes (“ramblas”): near Boca de los Frailes (36.8036°N, 2.1386°O), near Carboneras town (36.9667°N, 2.1019°O), at Almanzora river (37.3414°N, 2.0078°O) and near Paraje las Palmerillas, Estación Experimental Cajamar (36.7917°N, 2.6891°O). They were reared in individual tanks (22 cm x 18 cm x 18 cm) with the bottom filled with 2–3 cm of soil collected from one of the sites. All individuals were fed once a week with size-matched crickets (Gryllus assimilis Fabricius, 1775) purchased from the pet supply virtual store Exofauna (available at: https://exofauna.com). Spiders had access to water ad libitum through a 40 ml vial filled with water and covered with cotton. Vials were checked and refilled every 2-3 days. Holding tanks were placed in a climate ...,