Project Director

Hayes, Loren

Department Examiner

Gaudin, Timothy; Chatzimanolis, Stelios


Dept. of Biological and Environmental Sciences


University of Tennessee at Chattanooga

Place of Publication

Chattanooga (Tenn.)


Animal social systems are complex and the dynamics of one component could influence the dynamics of another. The aim of this literature search research was to determine the interrelatedness between mammalian social organization and mating system, two components of social systems. The mating system was represented by multiple paternity, the number of litters with more than one father, as genetic analysis tells which individuals reproduced with who. Variables that might influence multiple paternity amongst extant mammalian species included in this study are variable social organization, male social organization, mean litter size, sexual dimorphism, and phylogenetics. Analysis was conducted using 56 mammalian species from 97 population that made up 10 orders. The overall mean percentage of multiple paternity across all the male social organizations was 0.39. Analysis relieved that two hypotheses based on the variables above that were important effectors of multiple paternity included male social organization and mean litter size. Of the male social organization units, only multimale single female groups influenced multiple paternity, Multiple paternity was negatively correlated to mean litter size, which is the opposite of what other studies have found. Variable social organization, body mass, and phylogeny were not found to be important predictors of multiple paternity. The negative correlation between litter size and multiple paternity could be explained by mate guarding or improved by analyzing using a more holistic model. The statistical power of male social organization could be improved by creating less categories of male units as either multimale or single male. Other variables of interest to multiple paternity could be social structure, breeding season length, and environmental data. This study encourages the use of quality data and more natural history studies of animals.


I would like to thank my advisor, Dr. Loren Hayes, for supporting my academic growth during my undergraduate education. We have worked together on many projects, such as my thesis, and he has always been supportive every step of the way by providing feedback and guiding my understanding of behavioral ecology. We spent many hours deciphering difficult papers for my dataset. He guided the framework to my project, which evolved a few times into its final form, as well as the methodology for doing such a literature review and calculations. I thank him for finding a collaborator for my data analysis, Stephen F. Dobson, whom I thank for being passionate about my work. He analyzed my dataset quickly, generated the phylogenetic tree, adjusted to changes in the dataset forgivingly, and shared relevant publications with me. I thank Dr. Dobson for attending video calls with Dr. Hayes and me to discuss the results of his analysis, answering all my questions, and providing feedback on my methods section. I would also like to thank my committee for their attendance and feedback on my thesis defense. I thank Dr. Chatzimanolis for being willing to join my committee during my last semester. I thank Dr. Gaudin for his detailed edits on my thesis writing. I am also grateful to have received an URaCE SEARCH Award to support a salary so that I could dedicate my last semester to my thesis work. I thank the honors college for the opportunity to complete an undergraduate departmental honors thesis and I thank all those involved for their time signing paperwork and emailing. Lastly, I would like to thank my friends, family, and professors who joined my thesis defense. It was a pleasure to share my work with everyone and answer everyone’s questions.


B. S.; An honors thesis submitted to the faculty of the University of Tennessee at Chattanooga in partial fulfillment of the requirements of the degree of Bachelor of Science.




Mammals--Reproduction; Mammals--Behavior; Social behavior in animals


social organization; mating system; multiple paternity; phylogenetic signal; sexual size dimorphism; litter size


Animal Studies

Document Type



26 leaves







Appendix 1 Roberts DHON.xlsx (24 kB)
Full dataset at species and population levels.

Supplementary Materials 1 Roberts DHON.docx (47 kB)
Litter size correlation and R codes.

Supplementary Materials 2 Roberts DHON.docx (60 kB)
R analysis results