ISSN:
1420-9071
Keywords:
Photorefractory
;
yellow-throated sparrow
;
resonance
;
photophase
;
scotophase
;
Bünning hypothesis
;
circadian rhythmicity
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary Photorefractory male yellow-throated sparrows (Gymnorhis xanthocollis) were subjected to six resonance light cycles, consisting of 6 h basic photophase coupled with scotophases of longer durations (in cycles of 12 (6L∶6D) h, 24 (6L∶18D) h, 36 (6L∶30D) h, 48 (6L∶42D) h, 60 (6L∶54D) h and 72 (6L∶66D) h). Termination of photorefractoriness was evident in cycles of 24, 48 and 72 h, but not in 12, 36 and 60 h. The results are consistent with the ‘external-coincidence’ model (Bünning hypothesis) and suggest that endogenous circadian rhythmicity is involved in the termination of photorefractoriness.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01952090
Permalink