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Full-Text Articles in Life Sciences
The Ecology And Evolution Of Species Rarity In Oaks (Quercus Spp.), Yingtong Wu
The Ecology And Evolution Of Species Rarity In Oaks (Quercus Spp.), Yingtong Wu
Dissertations
Rare species are susceptible to extinction due to ecological and genetic factors. Understanding the distribution, ecology, and evolution of rare species can provide useful information for effective conservation. To investigate species rarity, this dissertation focuses on a species-rich and ecologically diverse genus, Quercus (oaks). In Chapter 1, I aimed to understand how interactions between hosts and soil microbes contribute to habitat restriction in oak species. I performed a soil inoculum experiment on two pairs of sister oak species that show habitat divergence. I found that host-specific soil microbes contribute to habitat divergence and exclusion among sister species of oaks, but …
Vines In The Neotropics: Phylogenomics, Biogeography And Systematics In Passion Flowers (Passiflora Subgenus Decaloba Section Decaloba), Serena Acha
Dissertations
With 600 species, Passiflora is a large, morphologically complex and broadly distributed genus in Passifloraceae that represents a major challenge to scientists interested in understanding the evolutionary history of tropical vines. Passiflora has been divided into subgenera, super sections and sections. One of the most enigmatic and species-rich (~120 spp.) groups in Passiflora is section Decaloba, which occurs in the Neotropics and is particularly diverse in Andean montane forests. In this study, we used phylogenomic and population genomic approaches to investigate the evolutionary history, biologeography, species boundaries, and taxonomy of Passiflora section Decaloba. We sampled herbarium specimens, extracted …
The Diversity, Costs, And Benefits Of Shelters Built By Lepidopteran Caterpillars In A Costa Rican Dry Forest, Christina Baer
The Diversity, Costs, And Benefits Of Shelters Built By Lepidopteran Caterpillars In A Costa Rican Dry Forest, Christina Baer
Dissertations
Thousands of Lepidoptera species build shelters as caterpillars using plant material and their own silk. Although these caterpillars and their shelters are recognized as playing important ecological roles, the structural diversity of shelters and the costs and benefits of different shelters to their builders are still poorly understood. In this dissertation, I use natural history observations, observational and manipulative field projects, and molecular and phylogenetic tools to investigate these questions for a diverse and abundant shelter-building caterpillar community within the dry forest of Palo Verde National Park, Costa Rica. In Chapter 1, I develop a system for categorizing and describing …
Diversification And Coexistence In The Madagascar Olive (Noronhia, Oleaceae), Cynthia Hong-Wa
Diversification And Coexistence In The Madagascar Olive (Noronhia, Oleaceae), Cynthia Hong-Wa
Dissertations
The long-isolated island of Madagascar provides a suitable setting for studying species diversification, with most groups of organisms there both radiating and showing a high level of endemism. Noronhia is one of these groups and represents the most successful radiation of the olive family (Oleaceae) in Madagascar, with ca. 80 species. In this study, using plastid and nuclear DNA sequences obtained from a comprehensive sampling both within Noronhia and the family, I show that Noronhia, together with Indian Ocean species of Chionanthus, form a monophyletic clade sister to African Chionanthus. The diversification of Noronhia followed a likely Cenozoic dispersal from …