Dev Biol 2017 08 25;428(1):101-117. Epub 2017 May 25.
Israel Oceanographic and Limnological Research, National Institute of Oceanography, P.O. Box 8030, Tel Shikmona, Haifa 31080, Israel. Electronic address:
Rough environmental conditions make the survival of many multi-cellular organisms almost impossible, enforcing behavioral, morphological, physiological and reproductive rejoinders that can cope with harsh times and hostile environments, frequently through down-regulation of metabolism into basal states of dormancy, or torpor. This study examines one of the most unique torpor strategies seen within the phylum Chordata, exhibited by the colonial urochordate Botrylloides leachi, which enters a state of hibernation or aestivation in response to thermal stress, during which all of its functional colonial units (zooids) are entirely absorbed and the colony survives as small remnants of the vasculature, lacking both feeding and reproduction organs. Tissue vestiges then regenerate fully functional colony when re-exposed to milder environmental conditions. Read More