Developmental strategies in an invasive spider: constraints and plasticity

Abstract

1. Growth defines the major life‐history traits such as size, weight, and age at maturity that determine an organism's fitness. Different models have been developed to describe growth by means of geometric progressions (e.g. Dyar's rule). However, growth forced along a geometric trajectory might constrain a plastic response to variable environmental conditions (e.g. food availability). 2. The present study investigated growth patterns under varying food conditions in the bridge spider, Larinioides sclopetarius, an extremely successful species in colonising urban habitats. 3. In L. sclopetarius growth ratios of successive instars were not constant but decreased over development. Instead, these spiders' growth is well described by a developmental growth rate (weight gain per moult) and a growth coefficient (weight gain per development time), both of which are based on a geometric progression. All developmental parameters, including developmental growth rate and growth coefficient as well as the intermoult duration and the number of instars, highly depend on food availability in L. sclopetarius and thus show plasticity. 4. Our study shows that geometric growth patterns do not necessarily preclude plasticity and that the parameters of geometric growth are affected by developmental plasticity. We suggest that their high developmental plasticity may facilitate bridge spiders' success in invading urban habitats.

Growth and Nest Hole Size Preferences in Immature Southern House Spiders (Araneae: Filistatidae): Are They Constrained Consumers?

“…Growth patterns and rules in spiders, the largest group of invertebrate predators, are poorly studied, but in general they follow a geometric progression, known as Dyar's rule (Kleinteich & Schneider 2011;Suter & Stratton 2011). The smooth log-log regression curves actually cloak the discontinuous nature of spider growth mandated by molting of the cuticle from one instar to another.…”

Contributions of juvenile and adult diet to the lifetime reproductive success and lifespan of a spider

“…A reduction in body size following food limitation has been reported in several arthropods (Bauerfeind and Fischer , Boggs and Freeman , Dmitriew and Rowe ). Yet in bridge spiders, previous studies have shown that food limited females will delay maturation but mature at a similar size as individuals provided with abundant food (Kleinteich and Schneider , ). Hence, this provides an interesting study system in which to compare the effects of juvenile and adult food limitation on lifetime reproductive success because it is unlike some other arthropod species in which a reduction in adult body size is a common mechanism through which juvenile food limitation affects female fecundity (Bauerfeind and Fischer , Boggs and Freeman , Dmitriew and Rowe ).…”

“…In addition to analysis of variance, we used Hedges’ g effect size to quantify the relative effects of juvenile and adult food limitation on fecundity and longevity. We predicted that juvenile food availability would have limited effects on lifetime reproductive success and lifespan compared to adult food availability, especially since juvenile food limitation does not affect adult body size (Kleinteich and Schneider , ).…”

Does allometric growth explain the diminutive size of the fangs of Scytodes (Araneae: Scytodidae)?

“…Growth patterns and rules in spiders, the largest group of invertebrate predators, are poorly studied, but in general they follow a geometric progression, known as Dyar's rule (Kleinteich & Schneider 2011;Suter & Stratton 2011). The smooth log-log regression curves actually cloak the discontinuous nature of spider growth mandated by molting of the cuticle from one instar to another.…”