An Intraoral Thermoregulatory Organ in the Bowhead Whale (Balaena mysticetus), the Corpus Cavernosum Maxillaris
Article first published online: 28 FEB 2013
Copyright © 2013 Wiley Periodicals, Inc.
The Anatomical Record
Volume 296, Issue 4, pages 701–708, April 2013
How to Cite
Ford, T. J., Werth, A. J. and George, J. C. (2013), An Intraoral Thermoregulatory Organ in the Bowhead Whale (Balaena mysticetus), the Corpus Cavernosum Maxillaris. Anat Rec, 296: 701–708. doi: 10.1002/ar.22681
- Issue published online: 18 MAR 2013
- Article first published online: 28 FEB 2013
- Manuscript Accepted: 3 JAN 2013
- Manuscript Received: 12 NOV 2009
- bowhead whale;
- corpus cavernosum
The novel observation of a palatal retial organ in the bowhead whale (Balaena mysticetus) is reported, with characterization of its form and function. This bulbous ridge of highly vascularized tissue, here designated the corpus cavernosum maxillaris, runs along the center of the hard palate, expanding cranially to form two large lobes that terminate under the tip of the rostral palate, with another enlarged node at the caudal terminus. Gross anatomical and microscopic observation of tissue sections discloses a web-like internal mass with a large blood volume. Histological examination reveals large numbers of blood vessels and vascular as well as extravascular spaces resembling a blood-filled, erectile sponge. These spaces, as well as accompanying blood vessels, extend to the base of the epithelium. We contend that this organ provides a thermoregulatory adaptation by which bowhead whales (1) control heat loss by transferring internal, metabolically generated body heat to cold seawater and (2) protect the brain from hyperthermia. We postulate that this organ may play additional roles in baleen growth and in detecting prey, and that its ability to dissipate heat might maintain proper operating temperature for palatal mechanoreceptors or chemoreceptors to detect the presence and density of intraoral prey. Anat Rec, 296:701–708, 2013. © 2013 Wiley Periodicals, Inc.