Male baleen whales have long been suspected to have annual cycles in testosterone, but due to difficulty in collecting endocrine samples, little direct evidence exists to confirm this hypothesis. Potential influences of stress or adrenal stress hormones (cortisol, corticosterone) on male reproduction have also been difficult to study. Baleen has recently been shown to accumulate steroid hormones during growth, such that a single baleen plate contains a continuous, multi-year retrospective record of the whale's endocrine history.
View Article and Find Full Text PDFCalanus finmarchicus, like many other copepods in the family Calanidae, can enter into a facultative diapause during the last juvenile phase (fifth copepodid, C5) to enable survival during unfavorable periods. Diapause is essential to the persistence of Calanus populations and profoundly impacts energy flow within oceanic ecosystems, yet regulation of diapause is not understood in these animals. Transcriptional profiling has begun to provide insight into metabolic changes occurring as C.
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