Muntjac Deer’s Bizarre Scent Glands Allow for Unique Cross-Species Communication
Have you ever seen a video of a deer with flappy skin on its face and wondered what it’s for? Well, it turns out that those flaps of skin are actually scent glands that muntjac deer use for communication!
Muntjac deer are a type of deer native to Southeast China and Taiwan, but they’ve been introduced to other parts of the world by humans. They live in the forest and are pretty small and secretive animals. They communicate with each other mostly through scent and the flappy skin on their faces plays a big role in that.
On the faces of muntjac deer are two sets of scent glands: the preorbital glands which are just in front of the eyes and the frontal glands which sit on the forehead. When a muntjac wants to communicate with other deer, it will flare these glands open, which makes them look pretty strange. The v-shaped frontal glands on the forehead are mostly used for scent marking the environment, and so muntjac will mostly keep them closed unless they’re rubbing their head on a tree trunk or branch. They will also flare their glands when excited, for example, if faced with a potential mate or a weird looking hairless primate.
Males will use their flaring face glands to scent mark more often than females and especially when in the company of other male muntjacs. They’ll use them to mark the ground, other deer, and flap them open while pooping and peeing. The musculature of the glands is such that they can open both preorbital glands together, both frontal glands together, or even flare all four at the same time, but the glands are always opened synchronously on both sides.
It’s pretty amazing how animals have evolved to communicate in different ways. The muntjac deer might look strange with their flapping face skin but it’s all for the purpose of communicating with other deer. Next time you see a video of a muntjac deer, you’ll know why it looks so peculiar. Just remember, it’s not a good idea to try and handle wild animals, so don’t go trying to tussle with a muntjac’s forehead!