monoculture of leafcutter ant gardens单一的切叶蚁花园.pdfVIP

Monoculture of Leafcutter Ant Gardens 1,2 1,2,3 1 1 1,4,5 Ulrich G. Mueller *, Jarrod J. Scott , Heather D. Ishak , Michael Cooper , Andre Rodrigues 1 Section of Integrative Biology, University of Texas at Austin, Austin, Texas, United States of America, 2 Smithsonian Tropical Research Institute, Balboa, Ancon, Republic ´ of Panama, 3 Department of Bacteriology, University of Wisconsin, Madison, Wisconsin, United States of America, 4 Center for the Study of Social Insects, State University ˜ ˜ of Sao Paulo (UNESP), Rio Claro, Sao Paulo, Brazil, 5 Department of Biological Sciences, Santa Cruz State University (UESC), Ilheus, Bahia, Brazil Abstract Background: Leafcutter ants depend on the cultivation of symbiotic Attamyces fungi for food, which are thought to be grown by the ants in single-strain, clonal monoculture throughout the hundreds to thousands of gardens within a leafcutter nest. Monoculture eliminates cultivar-cultivar competition that would select for competitive fungal traits that are detrimental to the ants, whereas polyculture of several fungi could increase nutritional diversity and disease resistance of genetically variable gardens. Methodology/Principal Findings: Using three experimental approaches, we assessed cultivar diversity within nests of Atta leafcutter ants, which are most likely among all fungus-growing ants to cultivate distinct cultivar genotypes per nest because of the nests’ enormous sizes (up to 5000 gardens) and extended lifespans (10–20 years). In Atta texana and in A. cephalot