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Full-Text Articles in Biology
Climate-Driven Change In Himalayan Rhododendron Phenology, Robert Evan Hart
Climate-Driven Change In Himalayan Rhododendron Phenology, Robert Evan Hart
Dissertations
Phenology – the seasonal timing of life-history events – is a critical dimension of natural history. It is also one of the earliest and most noticeable traits by which organisms respond to climate change. However, these responses are complex, and only beginning to be understood, especially in the montane and alpine environments that are among the ecosystems most vulnerable to climate change. Drawing from diverse data sets and employing multiple methodologies, I examined how climate affects phenology in Himalayan Rhododendron spp. Comprehensively monitoring flowering phenology over gradients of season and elevation on Mt. Yulong, China – home to a diverse …
The Evolution Of Floral Symmetry Across The Plant Order Lamiales, Jinshun Zhong
The Evolution Of Floral Symmetry Across The Plant Order Lamiales, Jinshun Zhong
Dissertations
Bilaterally symmetrical corollas have evolved independently numerous times from radially symmetrical ancestors and are thought to represent adaptation to specific pollinators. However, evolutionary losses of bilateral symmetry have occurred sporadically in different lineages. CYC2-like and RAD-like are genes needed for the normal development of bilateral symmetry in snapdragon corollas. However, exactly how changes in the floral symmetry patterning genes correlate with the origin and loss of floral bilateral remains poorly known. To address this question, a densely sampled phylogeny of CYC2-like genes across the order Lamiales was inferred and calibrated. The expression patterns of these genes in early diverging and …
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 …
Systematics And Floral Evolution In The Plant Genus Garcinia (Clusiaceae), Patrick Wayne Sweeney
Systematics And Floral Evolution In The Plant Genus Garcinia (Clusiaceae), Patrick Wayne Sweeney
Dissertations
The pantropical genus Garcinia (Clusiaceae), a group comprised of more than 250 species of dioecious, trees and shrubs, is a common component of lowland tropical forests and is best known by the highly prized fruit of mangosteen (G. mangostana). The genus exhibits as extreme diversity of floral form as is found anywhere in angiosperms and there are many unresolved taxonomic issues surrounding the genus. To understand patterns of floral evolution within the group and to evaluate morphology-based classification schemes involving Garcinia and its relatives, relationships among a broad sample of Garcinia and close relatives were inferred by conducting Bayesian, parsimony, …