Document: YAR-3-52-31

Body-size dependent species distribution of Israeli mammals on different ecological scales.

ZIV, Y.* and O.SHIMONI

Ben-Gurion University, Beer Sheva 84105, ISRAEL ¹

Abstract:
The body-size dependent distribution of Northern American mammals changes with ecological scale. On a local scale (habitat), species are distributed log-uniformly, while on the largest scale (North America), body-size and species distribution form a right-skewed-log-normal relationship. Hypothesizing that this pattern change requires environmental heterogeneity, we tested the prediction that Israel with its high environmental heterogeneity, would possess a similar pattern change in the body-size dependent distribution of its mammals. We collected geographic range and biogeographic data on all the Israeli mammals, excluding bats. We investigated three ecological scales: 1) All of Israel; 2) biogeographic zones -- Mediterranean, Irano-Turanian, and Saharo-Arabian; and 3) habitats -- Tsipori meadow (Mediterranean), Borot Lotz steppe (Irano-Turanian), and sandy, rocky and loessal habitats of the Negev desert (Saharo-Arabian). The mammalian distribution of body size across all of Israel revealed a right-skewed-log-normal relationship similar to that of North America. Furthermore, in specific habitats, the body-size distribution differed significantly from a log-normal distribution, indicating a relatively log-uniform distribution of body sizes. With respect to geographic range, middle-sized species had both a significantly higher coefficient of variance of their geographic range and a significantly lower minimal geographic range. The high similarity between North America and Israel in the change of body-size distribution with scale despite their huge difference in area suggests that environmental heterogeneity may serve as an important factor in determining this pattern.

Keywords: macroecology, body size, species diversity, scales, mammals, Israels

This abstract is being presented at: 11:30 AM in session:
Oral Session #21: Small Mammal Population Ecology.