Melatonin rhythms in the Australian freshwater crocodile (Crocodylus johnstoni): a reptile lacking a pineal complex?

@article{Firth2009MelatoninRI,
  title={Melatonin rhythms in the Australian freshwater crocodile (Crocodylus johnstoni): a reptile lacking a pineal complex?},
  author={B. T. Firth and K. Christian and I. Belan and D. Kennaway},
  journal={Journal of Comparative Physiology B},
  year={2009},
  volume={180},
  pages={67-72}
}
The vertebrate pineal gland is the primary source of melatonin, the rhythmic secretion of which is influenced by environmental light and temperature, thereby providing animals with information about seasonally changing photoperiod and thermoperiod. Although pineal glands are present in the majority of vertebrate species, a discrete organ is reported to be absent in the Crocodilia. However, if the melatonin rhythm is crucial to the survival of the organism, it would be expected that the rhythm… Expand
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