Pittendrigh C S, Skopik S D
Proc Natl Acad Sci U S A. 1970 Mar;65(3):500-7. doi: 10.1073/pnas.65.3.500.
A circadian oscillation (in the brain) of Drosophila spp. acts as a gating device restricting the emergence behavior of the adult to a limited fraction of each 24-hour cycle defined by that oscillator, but the oscillation does not gate intermediate steps of pupal development. Unlike the emergence act, such intermediate events in development occur at fixed times after prepupa formation and are totally independent of the phase of the ongoing oscillator that gates emergence behavior.
果蝇属（在大脑中）的昼夜节律振荡充当一种门控装置，将成虫的羽化行为限制在由该振荡器定义的每24小时周期的有限时间段内，但该振荡并不控制蛹发育的中间步骤。与羽化行为不同，发育过程中的此类中间事件在预蛹形成后的固定时间发生，并且完全独立于控制羽化行为的正在进行的振荡器的相位。
