Trait consistency over time is one of the cornerstones of animal personality. Behavioral syndromes are the result of correlations between behaviors. While repeatability in behavior is not a requirement for behavioral syndromes, the two concepts studied together provide a more comprehensive understanding of how behavior can change over ontogeny. The roles of ontogenetic processes in the emergence of personality and behavioral syndromes have received much individual attention. However, the characterization of both individual trait consistency and behavioral syndromes across both sexes, as in our study, has been relatively rare. Ontogeny refers to changes that occur from conception to maturation, and juveniles might be expected to undergo different selection pressures than sexually mature individuals and also will experience profound changes in hormones, morphology, and environment during this period. In this study, we test for behavioral trait consistency and behavioral syndromes across six time points during ontogenetic development in the desert funnel‐web spider (Agelenopsis lisa). Our results indicate behavioral traits generally lack consistency (repeatability) within life stages and across ontogeny. However, penultimate males and mature females do exhibit noticeable mean‐level changes, with greater aggressive responses toward prey, shorter latencies to explore their environment and in the exhibition of risk‐averse responses to predatory cues. These traits also show high repeatability. Some trait correlations do exist as well. In particular, a strong correlation between aggressiveness toward prey and exploration factors is observed in mature males. However, because correlations among these factors are unstable across ontogeny and vary in strength over time, we conclude that behavioral syndromes do not exist in this species. Nevertheless, our results indicate that increased consistency, increasing average trait values, and varying correlations between traits may coincide with developmentally important changes associated with sexual maturation, albeit at different time points in males and females. This period of the life cycle merits systematic examination across taxa.
Based on studies of adult behavior, the desert spider Agelenopsis aperta (Gertsch, 1934) is considered exemplary of a species exhibiting an aggressive syndrome. This study offers a first examination of the nature of interactions that juvenile A. aperta engage in during the period when sibs are clustered on a group web. We test the hypothesis that early instar A. aperta lack the aggressiveness noted for older instars. Our data set is comprised of observations of five weekly feedings offered to 818 sibling pairs, constituting an average of 4.6 replicate sib pairs from each of 174 families. At each weekly feeding, a worker termite was offered to each sib in the shared container in which they had built web retreats. We observed no cooperative foraging during the course of these feedings. Rather, most families exhibited a mix of independent foraging and non-injurious contests over prey. We present a brief overview of the occurrence and initiation of contests over prey, with particular reference to the weekly feeding in which contests first occur versus the feeding in which a seminal contest takes place (i.e., where sibs earn permanent winner versus loser status).
We describe a new spider species of the genus Agelenopsis Giebel 1869 (Agelenidae) from adult males and females. Agelenopsis riechertii is found in dry desert scrub habitats in the southwestern United States. While A. riechertii is similar to other sympatric congeners (A. aleenae, A. aperta, and A. spatula) in morphology and courtship behavior, it can be distinguished by an examination of its genitalia. Males possess an embolus that gradually narrows into a twisted tip which displays a convex edge from the lateral view. The female epigyna are harder to distinguish from congeners, but have a flatter anterior atrial edge that lacks strong bi-lobing. The spermatheca in female A. riechertii are also more elongate and comma-shaped than the other species. We describe the sequence of courtship behaviors exhibited by males, including the use of web pulses, abdomen waggling, and web flexing, in which males with fewer pauses, longer waggling bouts, and fewer web flexes are more likely to successfully copulate.
We made changes in the description of a new Agelenopsis spider species, Agelenopsis riechertae. Firstly, we declare the male holotype and a type repository to validate the species description, which was previously omitted. The original Latin name has been feminized from Agelenopsis riechertii to Agelenopsis riechertae.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.