Abstract
Pupation heights of various natural and laboratory populations ofDrosophila melanogaster, D. simulans, andD. pseudoobscura were observed in the laboratory under conditions of continuous darkness or continuous light. Generally higher mean pupation heights were observed under conditions of darkness.D. melanogaster tended to pupate higher than theD. pseudoobscura populations, andD. pseudoobscura tended to pupate higher thanD. simulans. The order of these species differences was similar whether pupation was measured in light or in darkness. Results of selection for pupation height inD. melanogaster suggest the presence of genetic variation for this character. The possibility that a relationship exists between adult and larval behaviors was explored by measuring the pupation heights of larvae from strains selected for geotactic behavior as adults, and also by measuring geotaxis of adults from strains selected for pupation height.