Meeting Abstract
Behavioural plasticity can increase individual fitness in the face of environmental changes. Nevertheless, correlated suites of behavioural traits (behavioural syndromes) can also be advantageous and these necessarily reduce plasticity. Here we measured a suite of behavioural traits in Australian redback spiders, Latrodectus hasselti, to determine (1) whether behavioural syndromes were present, (2) whether syndromes were plastic as a function of variation in diet (well-fed or unfed), and (3) whether variation in diet and behavioural traits of females was linked to offspring development, behaviour and fitness correlates (sibling cannibalism, size, longevity). Measured behavioural traits included latency to attack prey (voracity), boldness, latency to mate, and resting metabolic rate, in addition to web and body size in nature. We found that spiders showed repeatable voracity and boldness, and that individuals that attacked prey faster were also bolder. Unfed females were quicker to attack prey and bolder than well-fed females. We found transgenerational effects of maternal diet on offspring cannibalism rates, development, and behaviours. Offspring of fed females cannibalized more of their siblings than offspring of unfed females. Survivors of the cannibalism treatment were bolder and built webs faster than control individuals, and were also larger, developed faster, and survived to later instars. We conclude that Australian redback spiders have repeatable individual differences in behaviour along a boldness-aggression axis. Despite this syndrome, environmental variation can change behavioural correlations, and have physiological and behavioural effects that are apparently transmitted across generations.
