McLaughlin, Chris M.Sc. - Advisor: Prof. T.D. Nudds

SPATIAL SCALE AND VARIATION IN SPECIES RICHNESS: PATTERNS, PARAMETERS, AND PREDICTIONS

Species-area curves may be suitable baselines for measuring changes in species richness, but little is known of their variation among taxa and at differing spatial scales. I used published data for birds, herptiles, terrestrial mammals, plants, and bats to partition variation in species richness to area, biome, latitude, true islands and terrestrial islands, and hemisphere; generate species-area curves to similarly partition variation in the parameters (adding spatial scale explicitly); and calculate ratios of species-area curves among taxa, biomes, and area types—termed 'habitat allometry'. Species richness strongly correlated with area, latitude, and biome, although gradients in latitude and biomes were not consistently apparent. Bird, mammal, and plant species richness increased with area differently. Spatial scale affected the slopes of species-area curves. Species-area ratios suggested the potential for predicting species richness of uncensused taxa from known taxa (e.g. terrestrial mammals from birds in similar areas).