Anolis is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of lizard

Lizard

Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...

s belonging to the family Polychrotidae

Polychrotidae

Polychrotidae is a family of lizards commonly known as anoles . NCBI places the anole in subfamily Polychrotinae of the family Iguanidae. Four genera are common: Anolis, Norops, Phenacosaurus, and Polychrus....

. With nearly 400 species, Anolis represents the world's most species rich amniote

Amniote

The amniotes are a group of tetrapods that have a terrestrially adapted egg. They include synapsids and sauropsids , as well as their fossil ancestors. Amniote embryos, whether laid as eggs or carried by the female, are protected and aided by several extensive membranes...

 genus. Several species of Anolis are occasionally ascribed to the genus Norops

Norops

Norops is the proposed generic name for 150 lizard species traditionally classified in the genus Anolis . Guyer and Savage applied this name to a group that Etheridge designated the "beta anoles" on the basis of skeletal characters that distinguished them from all other anole species...

, but the validity of the Norops genus is not widely accepted. The Green Anole (Anolis carolinensis) has recently become the first reptile (not counting birds) to have its complete genome sequenced.
Anolis lizards are one of the best examples of both adaptive radiation

Adaptive radiation

In evolutionary biology, adaptive radiation is the evolution of ecological and phenotypic diversity within a rapidly multiplying lineage. Starting with a recent single ancestor, this process results in the speciation and phenotypic adaptation of an array of species exhibiting different...

 and convergent evolution

Convergent evolution

Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...

.