The relationship between offspring size and performance in the wolf spider Hogna helluo (Araneae: Lycosidae)

Life-history theory predicts a trade-off between number of offspring and investment (size) per offspring. An important component of this trade-off is how offspring size influences performance and survival. In this study, we examined the relationships between maternal size, offspring size and clutch size, as well as the relationship between offspring size and performance, in the wolf spider, Hogna helluo. Offspring dispersing from field-collected female Hogna helluo with egg sacs were counted and their carapace width was measured. The relationships between feeding performance (number of prey captured), starvation tolerance and offspring size were examined to determine if offspring size was correlated with offspring performance. Clutch size increased with female size, but there was little evidence for a trade-off between offspring size and number. Starvation tolerance and feeding performance were positively related to offspring size. Our results show that offspring performance increases with offspring size and are consistent with the hypothesis that parental fitness is maximized by producing as many offspring as possible given constraints on a minimum viable offspring size.