Reindeer Really Have Red Noses

Infrared image of a reindeer's head after a treadmill test shows the presence of a red nose. Credit: BMJ-British Medical Journal

A study published in the BMJ-British Medical Journal reveals why reindeer have red noses. Their noses are abundantly supplied with red blood cells through nasal microcirculation. Microcirculation is the flow of blood through tiny blood vessels. Red blood cells determine blood type and are also responsible for transporting oxygen to cells. Reindeer noses have a high density of blood vessels that supply a high concentration of red blood cells to the area. This helps to increase oxygen to the nose, control inflammation, and regulate temperature.

The study also found that compared to humans, reindeer have a higher density of mucous glands throughout their noses. According to the researchers, these glands help to "maintain an optimal nasal climate during changing weather conditions and extremes of temperature as well as being responsible for fluid transport and acting as a barrier." The researchers used infrared thermal imaging to visualize the reindeer's red nose.

Learn more about this study, see:

• Experts Discover Why Rudolph's Nose Is Red (Science Daily)