Variation in Tetragnathid spermathecal structures and sperm competition with descriptions of natural history

Persistent Link:
http://hdl.handle.net/10150/279954
Title:
Variation in Tetragnathid spermathecal structures and sperm competition with descriptions of natural history
Author:
Danielson-Francois, Anne
Issue Date:
2002
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
The study of variation in arachnid genitalic structures has contributed to the fields of systematics and sexual selection. Simon (1892--1903) in his Histoire Naturelle des Araignees first divided the ecribellate higher spiders into two groups, the Haplogynae and Entelegynae, using reproductive morphology. Spider genitalia have been used as a taxonomic tool for distinguishing between taxa because of their species-specific morphological variation. Variation in spider genitalic morphology has inspired evolutionary biologists to test mechanisms of sexual selection by which the variation could evolve, ranging from Fisherian run-away selection, chase-away selection, and sperm competition. The Tetragnathidae are particularly interesting for a comparison between haplogyne and entelegyne reproductive morphologies. Within this entelegyne family, a reversal to haplogyny has occurred. Fifteen representative members of this family and four outgroup taxa were examined with scanning and transmission electron microscopy in order to describe the fine structure of spermathecae, including the distribution and density of spermathecal gland pores. While the function(s) of the glandular secretion are unknown, the distribution and density of spermathecal gland pores is discussed with regard to possible functions of the glandular secretion. The potential influence of spermathecal gland secretions on mating behavior and sperm competition is considered. Sperm release patterns have been examined in entelegynes, but previously were not available for haplogynes. The relationship between copulation duration and sperm release was determined in Tetragnatha versicolor, the first examination of sperm release patterns in any haplogyne spider. In this species, copulation duration is not proportional to sperm release. To examine the relative influence of spermathecal morphology and numerical sperm competition on paternity, sperm release and paternity was assessed in the entelegyne Nephila clavipes and the haplogyne Tetragnatha versicolor. The data clearly support differential sperm release between males as the cause of previously reported first-male advantage in Nephila clavipes and the mixed paternity found for N. clavipes and Tetragnatha versicolor in this study. The natural history, mating behavior, and sperm release were determined for a previously unstudied tetragnathid species, Glenognatha emertoni . This is the second examination of haplogyne sperm release behavior as well as the first description of an unusual escape behavior.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Biology, Anatomy.; Biology, Entomology.; Biology, Zoology.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Ecology and Evolutionary Biology
Degree Grantor:
University of Arizona
Advisor:
Markow, Therese

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleVariation in Tetragnathid spermathecal structures and sperm competition with descriptions of natural historyen_US
dc.creatorDanielson-Francois, Anneen_US
dc.contributor.authorDanielson-Francois, Anneen_US
dc.date.issued2002en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThe study of variation in arachnid genitalic structures has contributed to the fields of systematics and sexual selection. Simon (1892--1903) in his Histoire Naturelle des Araignees first divided the ecribellate higher spiders into two groups, the Haplogynae and Entelegynae, using reproductive morphology. Spider genitalia have been used as a taxonomic tool for distinguishing between taxa because of their species-specific morphological variation. Variation in spider genitalic morphology has inspired evolutionary biologists to test mechanisms of sexual selection by which the variation could evolve, ranging from Fisherian run-away selection, chase-away selection, and sperm competition. The Tetragnathidae are particularly interesting for a comparison between haplogyne and entelegyne reproductive morphologies. Within this entelegyne family, a reversal to haplogyny has occurred. Fifteen representative members of this family and four outgroup taxa were examined with scanning and transmission electron microscopy in order to describe the fine structure of spermathecae, including the distribution and density of spermathecal gland pores. While the function(s) of the glandular secretion are unknown, the distribution and density of spermathecal gland pores is discussed with regard to possible functions of the glandular secretion. The potential influence of spermathecal gland secretions on mating behavior and sperm competition is considered. Sperm release patterns have been examined in entelegynes, but previously were not available for haplogynes. The relationship between copulation duration and sperm release was determined in Tetragnatha versicolor, the first examination of sperm release patterns in any haplogyne spider. In this species, copulation duration is not proportional to sperm release. To examine the relative influence of spermathecal morphology and numerical sperm competition on paternity, sperm release and paternity was assessed in the entelegyne Nephila clavipes and the haplogyne Tetragnatha versicolor. The data clearly support differential sperm release between males as the cause of previously reported first-male advantage in Nephila clavipes and the mixed paternity found for N. clavipes and Tetragnatha versicolor in this study. The natural history, mating behavior, and sperm release were determined for a previously unstudied tetragnathid species, Glenognatha emertoni . This is the second examination of haplogyne sperm release behavior as well as the first description of an unusual escape behavior.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectBiology, Anatomy.en_US
dc.subjectBiology, Entomology.en_US
dc.subjectBiology, Zoology.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineEcology and Evolutionary Biologyen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorMarkow, Thereseen_US
dc.identifier.proquest3050312en_US
dc.identifier.bibrecord.b42724028en_US
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