Date of Award

2001

Degree Name

Biological Sciences

College

College of Science

Type of Degree

M.S.

Document Type

Thesis

First Advisor

Thomas K. Pauley

Second Advisor

Donald Tarter

Third Advisor

Dan K. Evans

Abstract

Very few genera of vertebrates demonstrate variation in body size, color, pattern, and life history traits to the extreme that is demonstrated in the genus Desmognathus. Exact distribution of Desmognathus, as well as other genera of salamanders, is very difficult to outline because of hybridization between certain desmognathine species. Tooth morphology, tail keeling, head and body shape, and geographic location are factors used in the separation among species in this genus. There are five desmognathine salamanders, including D. monticola, D. fuscus, D. ochrophaeus, D. quadramaculatus, and 0. welteri in West Virginia. The purpose of this study was to analyze the morphological differences between males and females in the genus Desmognathus in West Virginia. Comparisons of morphological differences were made between northern and southern populations of each Desmognathus species found in West Virginia. Comparisons of morphological differences for each sex from northern and southern populations were made. Scanning electron microscopy was used to analyze tooth morphology for each species of salamander. Current literature was used to make conclusions about habitat and feeding niches. In desmognathine salamanders, males tend to reproduce earlier and at smaller sizes than females, but surpass females in body size as they age. Body size affects the number and quality of offspring, the ability to avoid predators, ability to obtain resources, and mates. Individuals from northern populations, which include the Allegheny Plateau, Allegheny Mountains, and the Ridge and Valley, were smaller because of the mountain populations. In the mountains, higher elevations, higher amounts of rainfall, and lower annual temperatures lead to rapid maturation and small body size because growth is secondary to maturation. Individuals from southern populations, which only includes the Allegheny Plateau, were larger because of low elevations, lower amounts of rainfall, and higher annual temperatures that lead to slower maturation and larger body size because growth continues until maturation is attained. Geographic variation can probably account for the differences in size between surrounding populations in other states when compared to West Virginia populations of 0. quadramaculatus and 0. welteri.

Subject(s)

Salamanders - West Virginia.

Desmognathus - Morphology - West Virginia.

Salamanders - Habitat - West Virginia.

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