Dewlaps are colorful flaps of skin that hang off the throats of male lizards. When deployed, this expandable fan can rapidly transform a lizard from drab to fab (as you can see in the picture above).

Fan-Throated Lizards (Sitana; Agamidae) are a widespread yet little-studied genus of lizards found in dry habitats throughout South Asia. Male lizards in this genus bear a fan-like structure under ...