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Updated: Jul 12, 2026

Reproductive Techniques for Ovarian Monitoring and Control in Amphibians
Published on: May 12, 2019
Refractoriness in female lizard reproduction: a probable circannual clock
Abstract:
Postreproductive Cnemidophorus uniparens maintained under free-running conditions of constant darkness for 7 months became reproductive at the same time as controls exposed to a long photoperiod. This lizard exhibits a pause in reproductive activity (refractory period) commencing in late summer in nature and terminating in mid-December in captivity. Both groups terminated refractoriness and started reproducing simultaneously in December despite maintenance of the experimental group in darkness since September. These results confirm the hypothesis that the refractory period in this lizard is under endogenous control.
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