| Summary: | Van Valen's Red Queen hypothesis states that within a homogeneous taxonomic group the age is statistically independent of the rate of extinction. The case of the Red Queen hypothesis being addressed here is when the homogeneous taxonomic group is a group of similar species. Since Van Valen's work, various statistical approaches have been used to address the relationship between taxon duration (age) and the rate of extinction. Some of the more recent approaches to this problem using Planktonic Foraminifera (Foram) extinction data include Weibull and Exponential modeling (Parker and Arnold, 1997), and Cox proportional hazards modeling (Doran et al. 2004,2006). I propose a general class of test statistics that can be used to test for the effect of age on extinction. These test statistics allow for a varying background rate of extinction and attempt to remove the effects of other covariates when assessing the effect of age on extinction. No model is assumed for the covariate effects. Instead I control for covariate effects by pairing or grouping together similar species. I use simulated data sets to compare the power of the statistics. In applying the test statistics to the Foram data, I have found age to have a positive effect on extinction. Submitted Note: A Dissertation submitted to the Department of Statistics in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Degree Awarded: Degree Awarded: Fall Semester, 2010. Date of Defense: Date of Defense: October 19, 2010. Keywords: Survival Analysis, Statistics, Red Queen Hypothesis, Planktonic Foraminifera, Extinction Bibliography Note: Includes bibliographical references. Advisory committee: Fred Huffer, Professor Directing Dissertation; William Parker, University Representative; Eric Chicken, Committee Member; Debajyoti Sinha, Committee Member.
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