Determining the effects of nutrition on the reproductive physiology of male mosquitoes

The content of this thesis was presented at the 2020 Denman forum at OSU, where it received 3rd place in its categoryThe effects of nutrition on aspects of insect physiology such as body size, nutrition, and fecundity are well-studied in some species, but we lack a detailed picture of how nutrition influences the reproductive physiology of insects such as mosquitoes. Given that mosquitoes such as the Northern house mosquito, Culex pipiens, are vectors of many deadly diseases and their ability to quickly proliferate, understanding their reproductive physiology is critical. To uncover the relationship between nutrition and the reproductive physiology of mosquitoes, we reared larvae of Cx. pipiens on a standard lab diet and divided adult males among three different dietary treatments: low (3%), moderate (10%), and high (20%) sucrose. After one week, we measured male accessory gland (MAG) size and utilized nuclear magnetic resonance (NMR) spectroscopy to measure and identify metabolites within the MAGs. We also measured total lipid and protein content in the bodies of adult male mosquitoes. Finally, we allowed males to mate with females to determine whether male nutrition influenced female fecundity. We found that males raised on the 3% sucrose diet had significantly smaller MAGs compared to males from the 10% and 20% sucrose diets. We also found that diet affected the metabolic composition of the MAGs, where some metabolites became differentially abundant as a result of diet. We could not identify the differentially abundant metabolites, but we were able to identify a small number of metabolites present in all MAGs. Diet did not affect whole-body protein content, but surprisingly, lipid content was highest in males from the low dietary treatment. We did not observe a relationship between male diet and female fecundity. Taken together, our results demonstrate that adult male diet does affect their reproductive physiology.NIH R21 grant awarded to Dr. Megan MeutiFoods for Health Discovery Theme (Dr. Matthias Klein)OSU Arts and Sciences Undergraduate Research Scholarship awarded to Derek HuckA one-year embargo was granted for this item.Academic Major: Evolution and Ecolog

Variação morfológica das genitálias femininas de lagartos da família Tropiduridae : forma, evolução e deslocamento de caracter

Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Zoologia, 2021.A genitália masculina vem sendo amplamente estudada, uma vez que mostra considerável variação morfológica entre os animais com fertilização interna. Por outro lado, pouco se sabe sobre a morfologia da genitália feminina. A genitália feminina tem sido negligenciada em diversos estudos seja por ser uma estrutura interna, de difícil acesso, ou pela percepção recorrente de ser uma estrutura de pouca ou nenhuma variação morfológica. Estudos recentes com genitália feminina apontam para uma variação maior que a esperada inicialmente, e uma clara coevolução entre estruturas masculinas e femininas, devido à interação direta na reprodução, podendo a evolução da genitália feminina ser motivada inclusive por conflitos sexuais. Técnicas que descrevam quantitativamente a variação morfológica observada, como a morfometria geométrica e estudos de padrões alométricos, são ferramentas poderosas para descrever e comparar estruturas morfológicas e vem demonstrando o quão a genitália feminina varia. Nessa dissertação, estudamos a morfologia genital feminina de espécies do gênero Tropidurus. Tropidurus é um gênero amplamente estudado, formado por grupos monofiléticos de espécies, com ampla distribuição e recente diversificação. Espécies do gênero podem ser encontradas em simpatria e sintopia em algumas regiões do Brasil, o que torna o grupo um excelente modelo para estudos de anatomia comparativa e deslocamento de caráteres genitais. Nesse estudo descrevemos qualitativamente e quantitativamente a variação da genitália feminina em diferentes níveis taxonômicos: entre grupos de espécies monofiléticos, entre espécies, dentro de uma espécie na variação ontogenética, e entre espécies próximas em um gradiente geográfico. Nosso estudo fornece uma discussão sobre a evolução da genitália feminina de lagartos, mostrando que a forma da genitália feminina varia, mesmo em espécies proximamente relacionadas e sugerindo que a ontogenia desempenha um papel importante na variação da forma genital feminina em lagartos tropidurídeos. Nosso trabalho sugere, ainda, que a competição interespecífica influencia o deslocamento de caráter na genitália feminina do grupo.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).The male genitalia has been broadly studied, as it shows considerable morphological variation between animals with internal fertilization. On the other hand, little is known about the morphology of female genitalia. The female genitalia has been neglected in several studies, either because it is an internal structure, difficult to access, or because of the recurrent perception that it is a structure with little or no morphological variation. Recent studies with female genitalia point to a greater variation than initially expected, and a clear co-evolution between male and female structures, due to direct interaction in reproduction, and the evolution of female genitalia may even be motivated by sexual conflicts. Techniques that quantitatively describe observed morphological variation, such as geometric morphometry and studies of allometric patterns, are powerful tools for describing and comparing morphological structures and have demonstrated how much female genitalia vary. In this dissertation, we study the morphology of female genitalia of species belonging to the genus Tropidurus. Tropidurus is a broadly studied genus, formed by monophyletic groups of species, with wide distribution and recent diversification. Species of the genus can be found in sympatry and symptopy in some regions of Brazil, which makes the group an excellent model for studies of comparative anatomy and displacement of genital characters. In this study we describe qualitatively and quantitatively the variation of female genitalia at different taxonomic levels: between groups of monophyletic species, between species, within a species in ontogenetic variation, and between closely related species in a geographic gradient. Our study provides a discussion of the evolution of female genitalia in lizards, showing that female genitalia shape varies even in closely related species and suggesting that ontogeny performs an important role in female genital shape variation in tropidurid lizards. Our work also suggests that interspecific competition influences the character displacement in the female genitalia of the group