Survival of the fittest in the Arctic requires more than just staying warm. A recent study published in the Biophysical Journal sheds light on the nose structure of Arctic seals and how it helps them adapt to the extreme cold.
Unlike their counterparts in milder climates, Arctic seals have adapted to have more convoluted nasal passages to minimize heat and moisture loss. The complex bones inside their nasal cavities, called maxilloturbinates, play a crucial role in warming and humidifying inhaled air, as well as reducing the amount of heat and moisture lost when they exhale.
Recent research has shown that Arctic seals can retain an incredible 94 percent of the moisture in the air when they breathe in and out. This incredible ability to efficiently preserve heat and moisture allows them to thrive in extremely cold conditions, which deplete energy and necessitate the replenishment of food.
But what makes the nose structure of Arctic seals so unique? Signe Kjelstrup, a co-author of the study and physical chemist at the Norwegian University of Science and Technology, states that “Arctic seal noses are sponge-like and very dense, whereas the Mediterranean seal nose has a more open structure.” The difference in maxilloturbinate structure is an adaptation unique to the Arctic that provides significant advantages in retaining heat.
Unlike reindeer, which also possess efficient heat exchange capabilities, Arctic seals are uniquely suited to live in one of the harshest environments on Earth. To further understand the evolutionary advantages offered by these adaptations, researchers used computer tomography to create 3D models of the nasal cavities of the Arctic bearded seal and the Mediterranean monk seal. Their findings provide invaluable insights into the impressive ability of Arctic seals to maintain efficient heat exchange even in the most extreme conditions.
For further reading on this fascinating study, click here.