1. Department of Solar Energy and Environmental Physics, Blaustein Institutes for Desert Research; Ben-Gurion University of the Negev; Sede Boqer Campus 8499000 Israel
2. Mitrani Department of Desert Ecology, Blaustein Institutes for Desert Research; Ben-Gurion University of the Negev; Sede Boqer Campus 8499000 Israel
3. Department of Biology; Washington University; St. Louis MO 63130 U.S.A.
4. Department of Evolutionary and Environmental Ecology; University of Haifa; Haifa 31905 Israel
5. Department of Life Sciences; Ben-Gurion University of the Negev; Beer-Sheva 84105 Israel
6. Department of Ecology and Evolutionary Biology; Princeton University; Princeton NJ 08544 U.S.A.