What is a dewlap? Dewlap is the name of the flap of skin underneath the lower jaw that stores extra fat. A great majority of mammals, birds, reptiles and amphibians have a dewlap. In some species, it is more prominent. What’s a dewlap’s purpose? That depends on the species of animal. Let’s look at a rabbit’s and an anole lizard’s dewlap:
Mature females have a pronounced dewlap. However, don’t assume that just because you can see your rabbit’s dewlap that it’s a female. Obese males sport prominent dewlaps too. Why does a female need a prominent dewlap? When she becomes pregnant and needs to build a nest to give birth, she’ll pluck out the fur from her dewlap to line her nest. When she experiences a false or pseudo-pregnancy, if she’s stressed or experiencing a hormonal imbalance, she’ll also pluck out her dewlap fur.
By the way, a normal dewlap should feel fleshy and soft and not have swelling or a hardness to it. A dewlap can be easily checked. Just gently pull the dewlap away from the neck.
The male anole lizard have brightly colored dewlaps that they use to attract a mate or warn a rival. To a female anole lizard, the bigger and brighter the dewlap, the better they’ll like him.
Still confused about what exactly a dewlap is? Find a senior citizen or an overweight human. That “double chin” — that’s what a dewlap is.