Question

• Can you think of a way to alter Achaearanea tepidariorum’s probability of prey capture?
• Identify a variable to test and propose a hypothesis that clearly states how the variable will influence prey capture.

Answer 1

Answer.Achaearaena tepidariooums common house
spiders (Achaearanea tepidariorum) change their silk properties in function of their prey
type (cricket or pillbug). Silk properties also differ between different regions of the
cobweb spun by a common house spider. However, silk properties did not differ for other
species (black widows and bridge spiders). Major ampullate silk plasticity increased
during spider evolution. Silk plasticity may be mediated by a valve present in the
spinning duct of Orbicularia, which allows them to apply shear forces during forcible
silking and control their speed during falls. Silk plasticity may have been selected for as
spiders make more diverse uses of their major ampullate silk.
predator–prey systems, may be particularly strong predictors of ecological outcomes. Here, we test the predator–prey locomotor crossover hypothesis, which predicts that active predators are more likely to encounter and consume prey with the opposing locomotor tendency. We test this hypothesis using intraspecific behavioral variation in both a predator and prey species as predictors of foraging outcomes. We use the old field jumping spider, Phidippus clarus (Araneae, Salticidae), and the house cricket, Acheta domesticus (Orthoptera, Gryllidae), as a model predator–prey system in laboratory mesocosm trials.