Arnold 9407844 This project explores the nature of variation among different populations of the mountain dusky salamander along an elevational cline in the southern Appalachian mountains. Two populations that have been studied show pronounced differences in many life history characters such as body size, egg size, and clutch size. Such patterns are extremely common in a wide diversity of animals, but ecologists know surprisingly little about the underlying reasons for this clinical variation. Previous work suggests that the early life stages of these salamanders seem to be the most sensitive to variation in local habitats. For example, the harsh winters of high elevation sites are thought to exact a far more severe toll on larval growth rates than low elevations sites. The goal of this study is to rigorously study the possible ways in which these differences in the habitat may contribute to the overall patterns that have been observed. Concomitantly, it will be possible to critically explore various ways in which the salamanders are moved between habitats, after which their growth will be monitored in each habitat. In general this work will be of interest to biologists who will study clinical variation. One potential applied use of this research is to understand how organisms such as these salamanders will respond to global warming. This is, by studying the ways in which salamanders have already responded to clinically varying temperature and habitat differences, it will be possible to gain insights into the more general issue of how warmer and drier climates will influence the survival and distribution of many species. This information, in turn, is highly relevant to attempts to manage biological diversity in the richly diverse southern Appalachians, much of which is held in the National Parks and National Forests.
