Sexual selection in spiders
[7] Size is a factor in the reproductive success of males with species such as Stegodyphus lineatus, Argiope aurantia and Argyroneta aquatica showing sexual dimorphism, beneficial for larger males, stronger and more aggressive, who fight off the smaller ones using their large chelicerae and forelegs.
[1][8] This leads to a decrease in the paternal success for smaller males since they are unable to gain access to females.
[2] In spiders like Tetragnathidae, Araneidae, Thomisidae and Pholcidae[11] there is an optimal body size that favors climbing speed.
[12] This optimal body size for climbing is observed in different males from the same species express phenotypes, weapons such as chelicerae, teeth or even legs to fight off competition are used to fight off oncoming rivals, with larger bodied spiders contained larger chelicerae.
Smaller males tend to have a quick development time which gives them an advantage in mating with a female.
The embolus that is found in the female's posterior receptaculum suggests that males are trying to limit sperm competition.
[16] For example, in the spider species Argiope aurantia, males will sometimes plug a female with both pedipalps to prevent sperm competition.
Males who are able to adapt to the changes in food availability are well conditioned and usually show courtship displays such as tapping on their forelegs and waving.
[3] Courtship displays, such as degrees of ornamentation, colors, and movements, are commonly expressed in individuals of a species to attract the opposite sex.
Females are able to be choosy when courtship rates are high because they do not have to worry about missing out on copulations if there are plenty of male spiders to mate with.
In several species of jumping spiders, including Habronattus pyrrithrix, and Cosmophasis umbratica, males show different brightness and color of body parts prior to copulation.
[3][4][5][20][21] In the orb weaving spider Zygiella x-notata, reproduction rates are affected by male choice under different conditions.
The males from the species Latrodectus hesperus show high mate preference for better conditioned females.
By choosing well nourished females, males are able to increase their mating success while limiting their chance of being consumed.
[7][23] For example in the Argiope bruennichi species, males produce energetic courtship displays prior to copulation.
