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Integrating The Effects Of Biotic Interactions Into Models Of Species Distributions, Jamie M. Kass Feb 2019

Integrating The Effects Of Biotic Interactions Into Models Of Species Distributions, Jamie M. Kass

Dissertations, Theses, and Capstone Projects

The study of species geographic distributions and their environmental drivers has developed at a fast pace in recent years, owing to improvements in technology and data availability, and is increasingly relevant in this era of advancing global change. Currently, the field focuses heavily on a variety of techniques to statistically estimate species’ ranges I refer to collectively as species distribution models (SDMs). These models are now used across a wide range of disciplines, but inadequacies remain in implementation, methodology, and theory that are in need of new insight. In this thesis I will address two key shortcomings that require improvement …


Integrating Phylogenomics, Biogeography And Systematics To Explore The Taxonomy And The Rise Of The Ratsnakes, Xin Chen Feb 2015

Integrating Phylogenomics, Biogeography And Systematics To Explore The Taxonomy And The Rise Of The Ratsnakes, Xin Chen

Dissertations, Theses, and Capstone Projects

Understanding the evolutionary processes that create the spectacular diversity of organisms, both in species numbers and form, is a primary goal for biologists. Global ratsnakes are a species-rich assemblage with high morphological and ecological diversity and a distribution that encompasses both the Old World (OW) and the New World (NW). To explore the mechanism leading to the divergence of the ratsnakes, I tested the hypotheses regarding the area of origin and global dispersal, and examined the patterns of diversification and trait evolution. Given adaptive radiation via ecological opportunity, a diversity-dependent diversification pattern and an early burst trait evolutionary pattern are …


Systematics And Biogeography Of Orthaea Kloztsch (Ericaceae: Vaccinieae), Nelson Salinas Feb 2015

Systematics And Biogeography Of Orthaea Kloztsch (Ericaceae: Vaccinieae), Nelson Salinas

Dissertations, Theses, and Capstone Projects

In the first chapter a study of the distribution patterns of the neotropical Vaccinieae (Ericaceae) is presented. Five areas of endemism were recovered: Central America, northern Chocó, southern Chocó, eastern Ecuador, and Yungas. Divergence times estimations indicate that the Andean clade of Vaccinieae migrated to South America during the Late Oligocene or Early Miocene (28.9-17.84 MA), and most of the subsequent diversification took place during the Tertiary. The Yungas was the first Andean area to be colonized, and several dispersals towards the north expanded their distribution range. Both areas of endemism and dispersal events were influenced by geological processes, such …


The Effects Of Pleistocene Climatic Change On The Phylogeography Of Euploea Mulciber (Lepidoptera; Nymphalidae; Danainae), Elva Yang Jan 2012

The Effects Of Pleistocene Climatic Change On The Phylogeography Of Euploea Mulciber (Lepidoptera; Nymphalidae; Danainae), Elva Yang

Dissertations and Theses

No abstract provided.


The Effect Of The Study Region On Gis Models Of Species Geographic Distributions And Estimates Of Niche Evolution; Preliminary Tests With Montane Rodents (Genus Nephelomys) In Venezuela, Ali Raza Jan 2010

The Effect Of The Study Region On Gis Models Of Species Geographic Distributions And Estimates Of Niche Evolution; Preliminary Tests With Montane Rodents (Genus Nephelomys) In Venezuela, Ali Raza

Dissertations and Theses

Various niche-based techniques exist to model a species' potential geographic distribution in a Geographic Information Systems (GIS) framework. These models compare the environmental conditions of localities of a species' occurrence versus those of the overall study region. In addition to uses in areas such as macroecology and conservation biology, this approach has been applied recently to studies of niche evolution and historical biogeography. Definition of the study region is critical for all of these applications but has not been addressed previously. Here, I examine the effect of changes in the extent of the study region on potential distribution models of …