Alexis Harrison and I have spent the last two days on Grand Cayman collecting tail tips from Anolis sagrei. During our work, we’ve seen quite a few A. conspersus. Anolis conspersus is nested within the Jamaican A. grahami, splitting away approximately 2.5 to 3 million years ago when it colonized Grand Cayman. Both species vary in body color across their range from brown to drab green to emerald green to blue green with white mottling.
They are very different, however, in the dewlap. Anolis grahami’s dewlap reflects strongly in the long wavelengths, being orange with a yellow margin. The dewlap of A. conspersus, on the other hand, reflects in short wavelengths being blue and UV-bright.
Anolis grahami - Jamaica
Anolis conspersus - Grand Cayman
In his 2001 paper, Joseph Macedonia suggested that the blue and UV-bright dewlap of A. conspersus may have evolved to be an effective signal in the UV-rich shade, which “proto-conspersus” would have been using heavily to avoid water loss on a xeric, newly emerged Grand Cayman.
Anolis conspersus
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