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 ...,生物对同种个体带来的风险可能表现出不同的应对策略，但此类应对差异的成因至今仍不明确。本研究采用半同胞/全同胞设计（half-sib/full-sib design），旨在探究（间接）遗传效应与环境效应对同类相食的带纹狼蛛（Lycosa fasciiventris，Dufour, 1835）针对同种信号的行为响应的贡献程度。研究结果显示，狼蛛在存在或不存在同种信号的斑块上的相对停留时间、活动度与移动速度均存在差异，但仅在停留时间这一性状中检测到了直接遗传方差。上述三个性状间存在相关性，可被整合为一个主成分（principal component）：在带有同种信号的斑块中停留时间更长的狼蛛，在该区域内的移动频率更低、移动速度也更为缓慢。配对个体的头胸甲宽度与体重损失的遗传和/或环境组分，与目标个体的主成分得分存在显著相关性。此类性状的个体差异或可反映信号产生的质量与/或数量…… 蜘蛛采集与饲养条件 本研究中的带纹狼蛛（Lycosa fasciiventris）成体雄性与亚成体雌性个体，于2015年6至7月间采集自西班牙东南部阿尔梅里亚省四处不同地点的季节性干河床（ramblas）：分别位于博卡德洛斯弗赖莱斯附近（36.8036°N，2.1386°W）、卡瓦内拉斯镇附近（36.9667°N，2.1019°W）、阿尔曼佐拉河沿岸（37.3414°N，2.0078°W），以及卡哈马尔实验站帕尔哈利亚拉斯地区附近（36.7917°N，2.6891°W）。所有个体均被单独饲养于尺寸为22 cm × 18 cm × 18 cm的饲养箱中，箱底铺设2至3厘米厚的采集自上述某一采样点的土壤。所有个体每周投喂一次体型匹配的蟋蟀（Gryllus assimilis Fabricius, 1775），饲料购自宠物用品虚拟商店Exofauna（官网：https://exofauna.com）。狼蛛可通过一个装有清水并以棉塞封口的40ml玻璃瓶自由获取饮用水，饲养人员每2至3天检查一次并更换瓶内清水。饲养箱被放置于气候控……