The nasal cavity of the bearded seal: An effective and robust organ for retaining body heat and water

• Main Authors: Cheon, Hyejeong Lee, Kizilova, Nataliya, Flekkøy, Eirik, Mason, Matthew, Folkow, Lars, Kjelstrup, Signe
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2024
• Subjects: bearded seal; Erignathus barbatus
• Online Access: https://www.repository.cam.ac.uk/handle/1810/373120; https://doi.org/10.17863/CAM.111671

We report the effects of varying physiological and other properties on the heat and water exchange in the maxilloturbinate structure (MT) of the bearded seal (Erignathus barbatus or Eb) in realistic environments, using a computational fluid dynamics (CFD) model. We find that the water retention in percent is very high (about 90%) and relatively unaffected by either cold (-30°C) or warm (10°C) conditions. The retention of heat is also high, around 80%. Based on a consideration of entropy production by the maxilloturbinate system, we show that anatomical and physiological properties of the seal provide good conditions for heat and water exchange at the mucus lining in the seal’s nasal cavity. At normal values of tidal volume and maxilloturbinate (MT) length, the air temperature in the MT reaches the body temperature before the air has left the MT channels. This confers a safety factor which is expected to be helpful in exercise, when ventilation increases. Faculty of Science, The Norwegian University of Science and Technology; Research Council of Norway, Center of Excellence Funding Scheme