Evolutionary Patterns of Trilobites Across the End Ordovician Mass Extinction
Issue Date
2013-05-31Author
Congreve, Curtis Raymond
Publisher
University of Kansas
Format
260 pages
Type
Dissertation
Degree Level
Ph.D.
Discipline
Geology
Rights
This item is protected by copyright and unless otherwise specified the copyright of this thesis/dissertation is held by the author.
Metadata
Show full item recordAbstract
The end Ordovician mass extinction is the second largest extinction event in the history or life and it is classically interpreted as being caused by a sudden and unstable icehouse during otherwise greenhouse conditions. The extinction occurred in two pulses, with a brief rise of a recovery fauna (Hirnantia fauna) between pulses. The extinction patterns of trilobites are studied in this thesis in order to better understand selectivity of the extinction event, as well to understand the effect of the extinction of the evolution of various trilobite groups. To study these patterns two phylogenetic analyses of sphaerexochines and ceraurids were generated and the overall data was combined with two older analyses of homalonotids and deiphonines from my Masters Thesis. Speciation and extinction rates were estimated in the deiphonines and sphaerexochines (two closely related cheirurid clades) to understand the different patterns of extinction and survivorship in greater detail. Then, utilizing the phylogenetic analyses, the end Ordovician is reinterpreted as a large scale analog of Vrba's Relay Model, referred to herein as the Cladal Turnover Model.
Collections
- Dissertations [4625]
- Geology Dissertations and Theses [232]
Items in KU ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.
We want to hear from you! Please share your stories about how Open Access to this item benefits YOU.