Oviposition was compared at laboratory temperatures ranging from 3-38C and at 100% relative humidity for four Drosophila species triads from different ecological backgrounds. Oviposition temperatures common to all three species in a triad reflect the group's ecological distribution: the temperate-montane virilis group (D. virilis, D. americana, D. montana) has the lowest temperature limits (9-32C), the desert repleta group (D. arizonensis, D. moJavensis, D. mullerz) has the highest limits (12-36C), and the cosmopolitan melanogaster group (D. melanogaster, D. simulans, D. ananassae) has broader temperature limits (10.5-34C) than the endemic tropical willistoni group (D. paulistorum semispecies-Amazonian, Interior, Transitional: 10.5-30C). Within triads, differentiation in oviposition temperature usually reflects species' distributions and suggests microniche differences among species. Sibling species in each triad are not necessarily more similar in oviposition capabilities. Patterns of differences suggest that temperature-dependent oviposition may be important for the separation of these closely related species. Individual species from different triads show overlap in oviposition temperature range, suggesting caution when generalizing about widespread vs. ecologically restricted groups. Observed oviposition temperatures extend beyond limits predicted in the literature for resource utilization, and may not correspond to temperature limits for tolerance/survival, developmental viability or activity in the field. Associated components of reproduction (mating and oviposition) are differentially affected by temperature in all 12 species. This emphasizes the fact that if temperature is of adaptive importance for a particular species, different aspects of the life cycle can be the critical temperature-limited factor.

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