dewlaps and anoles

 “Hey mister, show me your blanket!”  “Lizard, lizard, show me your gizzard!”  These are familiar chants to many New Orleanians and refer to a characteristic of one of our most familiar local denizens, the Green Anole (Anolis carolinensis), frequently called the American Chameleon because it can change color from green to brown.  Unique to males, the “blanket” is actually called a dewlap, or throat fan.

Green Anoles use their pink dewlaps for two purposes.  One is for breeding, displaying their intent to females.  The other is by far the most commonly seen behavior and functions in establishing the male’s territory among other males.  By displaying its dewlap, the lizard tells other males that they have entered the displayer’s home range.  The intruding male has two options.  He may simply leave, or he may establish his dominance and displace the original proprietor.  Males rarely give females a territorial display, allowing them to enter freely.  As you have probably noticed, anoles will also display to gardeners, dogs, and other passers-by.

The dewlap is erected by the movement of the hyoid apparatus, a set of bones derived from the gill support of fish and functioning in tongue support for most land vertebrates, including humans.

The next time you see an anole showing his dewlap, notice that he is also bobbing up and down.  This is also a vital aspect of the communique.  There are many species of anoles in the New World and, as you might suspect, each has a differently patterned dewlap and a different bobbing sequence, thus allowing them to remain as separate breeding populations in a seemingly overlapping habitat.  New Orleans has a newly arrived anole species, the Brown Anole (Anolis sagrei).  It is brown, cannot change colors, and has a red dewlap