The dewlap is an extra flap of skin or fleshy fold that hangs just below an animal’s chin or neck. It is prominent in animals such as rabbits, lizards, birds, dogs, and some types of cattle. While dewlaps tend to stand out in males more than females, this is often not the case with rabbits.
So, what exactly is this fleshy piece of skin meant to do? In this guide, we explore what a dewlap is, which animals have them, and what makes this strange appendage so special.
Dewlaps Serve Different Purposes in Different Animals
You can find dewlaps in anole lizards, reindeer, and even certain dog breeds. However, the dewlap doesn’t serve the same purpose in every species. Take rabbits, for example. The dewlap in female rabbits provides an extra mound of fur below their chins which they use to build nests. By plucking the fur around the dewlap, they create a warm and snug burrow for their offspring. In anole lizards, the flap of skin below the chin is expandable and used to attract females during mating season.
Dewlaps are certainly an unusual feature, but apart from their odd appearance, these growths serve many practical purposes.
Dewlaps Offer Many Species-specific Benefits
Dewlaps are an integral part of an animal’s anatomy and, in some cases, biological function. In moose, dewlaps are known as bells, and they play a vital role in courtship. A male moose, otherwise called a bull, will enlarge his dewlap to attract females (called cows)
Some researchers believe that the dewlap is more significant than impressing the ladies! Ecologist Dr. Jakob Bro-Jørgensen proposed that dewlaps help animals, such as the moose and South African eland, with thermoregulation. Theories suggest that the dewlap can dissipate heat by transferring it from the blood vessels in this throat adornment to the surrounding air. It may also be used as a form of defense in lizards and birds by making them appear larger and more threatening.
In lizards and birds, the fleshy throats are primarily used for communication. Lizards and birds in particular will expand their throats to display vibrant colors and patterns when looking for a partner. In more common bird species like chickens, turkeys, and vultures, the wattles are considered dewlaps.
Dewlaps vs. Medical Problems
While dewlaps are known as jowls in animals, they aren’t generally associated with obesity. As noted, these are unique physical features that offer many benefits. However, a bulging dewlap in bunnies and dogs could indicate that they’re overweight. The only way to determine whether this appendage is a healthy size is to feel for loose skin compared to a soft, large ball or roll. Dewlaps are hanging skin, so one shouldn’t feel firm like a piece of fat.
Apart from obesity, a dewlap could be concerning when it appears disproportionate to the animal’s relative body size. In dogs and rabbits, an enlarged skin fold below the chin could reveal swelling due to an infection. Other issues that occur in this area include lymphedemas, allergic reactions, and lipomas. If you notice any troubling physical changes in your pet, consult their veterinarian sooner rather than later. Do not attempt to lance or drain the mass, as this could cause further problems.
Do Animals Need Dewlaps?
Dewlaps offer many benefits, but animals don’t necessarily need them to survive. While it’s presumed that the fleshy skin fold helps regulate temperature in large-hoofed animals, known as ungulates, it is not linked to survival. Large bucks may rely on their dewlaps to cool down in hot periods. However, these animals have other ways of adapting to their surroundings. For example, the dewlap in a moose is believed to provide thermoregulation; however, these animals will wallow in lakes when they overheat. While birds, lizards, and other mammals have dewlaps, ultimately, they do not depend on this appendage for survival.
Fun Facts About Dewlaps
Dewlaps are strange physical features, but they certainly help feathered, hoofed, and scaly animals thrive in different ways. Some fun facts about these growths include:
- In camels, the dewlap is called a gula (or dulla) and is most prominent in males. The air sac located below the throat is inflatable and used to attract females and assert dominance over rivals.
- Similarly, moose will size each other up based on the appearance of their dewlaps. The bull with the bigger fold and impressive display is usually the victor.
- Some animals store fat in their dewlaps. Rabbits, such as Flemish giants, will use the fat around their throats to sustain themselves when food runs out. Hopefully, this wouldn’t happen if you have one as a pet! These lagomorphs need a steady diet of hay to stay healthy.
Another fact about dewlaps is that they do not grow back. While a lizard can regenerate its tail, it cannot regenerate another dewlap. And, because this growth is so close to the throat, a deep cut could prove serious!
Conclusion: Dewlaps Offer Many Benefits to Animals
They might be large and fluffy in some, and thin and fleshy in others, but regardless, dewlaps help animals communicate in many ways. From a large moose to a tiny anole, animals with dewlaps use these appendages to communicate dominance or put on their best courtship display.
