HERITABLE VARIATION FOR TERRITORIAL SUCCESS IN FIELD-COLLECTED DROSOPHILA-MELANOGASTER

Drosophila melanogaster males were collected from two field sites and tested for territorial success in the laboratory. The territorial and nonterritorial males were crossed with females from an inbred strain, and progeny cultured in the laboratory were characterized for territorial success. For one field site, progeny from territorial parents were relatively more successful than progeny from nonterritorial parents, indicating heritable variation among males from the field. No heritable differences were found for the other field site. Evidence for heritable variation in this one-generation test was also obtained for males from a laboratory stock. Territorial males from the field sites and from laboratory cultures were heavier than nonterritorial males. However, heritability for body weight in the field was low, and weight did not contribute to heritable variation in territorial success except in experiments with the laboratory stock.