“…Only one case of larval diapause (D.deJ7exa) and pupal diapause (D.aEpina) are known (Basden, 1954;Lumme et al, 1978). In contrast to other insects studied (see for example, Love & Welchel, 1955;Earle & Newsom, 1964), imaginal diapause in Drosophila appears to be determined by environmental conditions in the first few days of adult life, rather than in a preceding pre-adult stage. This feature, in conjunction with the three environmental cues, has resulted in a life history pattern that is extremely flexible and responsive to local and seasonal environmental heterogeneity.…”