Battle of the Sexes: When Dewlaps Differ

Anolis insignis above, Anolis transversalis below. Males on left, females on right. Photos appeared in Lizards in an Evolutionary Tree, photographed by Steve Poe (insignis), Arthur Georges (male transversalis) and Alexis Harrison (female transversalis).

Sexual dimorphism–differences between the sexes–have been greatly studied in anoles, and so has dewlap color and patterning. But little research has been directed to the phenomenon of sexual differences in dewlap color or pattern. Such differences are relatively rare in Caribbean islands, but much more common in mainland species. Why does this occur? Nobody knows. In fact, what female anoles use their dewlaps for has been little studied (another phenomenon, fodder for a future post, is differences in the size of the dewlap between the sexes, which can be quite substantial).

In any case, here’s a sampling of dimorphic dewlaps.

Anolis fitchi (female and male), and Anolis orcesi (female and male)

Photos courtesy Melissa Woolley.

Anolis lyra, female on left (photos courtesy Fernando Ayala).

Photos courtesy of Fernando Ayala

Anolis fowleri, as documented by Dan Scantlebury here.

And a recent post has just discussed this phenomenon in Venezuelan anoles, such as this one.

Anolis tigrinus, male on left, female on right. From Ugueto et al., Carib. J. Sci., 2009.

• Author
• Recent Posts

Jonathan Losos

Professor of Biology and Director of the Living Earth Collaborative at Washington University in Saint Louis. I've spent my entire professional career studying anoles and have discovered that the more I learn about anoles, the more I realize I don't know.

Latest posts by Jonathan Losos (see all)

• New Article on Anolis roosevelti and the Question of Its Survival - March 16, 2024
• Lizard Diving Champions: Trading Heat For Safety Underwater - March 15, 2024
• Do Large Brown Anoles Get the Most Mating Opportunities? - January 6, 2024