Anolis cristatellus, commonly known as the Crested Anole, is endemic to Puerto Rico, belonging to the Caribbean lineage. It is classified as a trunk-ground ecomorph, commonly found in warmer, drier environments such as coastal forests and urban areas. 

This species is easily identified by its dark brown coloration, muscular build, and distinctive crest that runs along the back and tail. Unlike its trunk-crown relatives, A. cristatellus is highly territorial and displays a range of aggressive behaviors, including push-ups, dewlap extension, and head-bobbing. 

Its ecological flexibility has made it a valuable subject for studies on thermal tolerance, behavioral adaptation, and urban evolution. It frequently coexists and competes with trunk-crown anoles in overlapping habitats, making it central to research on niche partitioning and microhabitat competition. Its capacity to thrive in urbanized areas and adapt to varying environmental conditions showcases another facet of adaptive radiation among Caribbean anoles. 

Native to Cuba, Anolis sagrei, better known as the Brown Anole, has become one of the most widespread and studied anole species due to its successful introduction to Florida, the Bahamas, and other parts of the mainland. 

It belongs to the trunk-ground ecomorph, frequently seen on low vegetation, shrubs, and at ground level in both natural and urban environments. This small, brown lizard is easily recognized by its reddish-orange dewlap and short, sturdy limbs designed for quick terrestrial movement. 

Its strong hind limbs and behavioral plasticity have enabled A. sagrei to colonize a wide range of environments and outcompete native species such as A. carolinensis in parts of the southeastern U.S. As a model organism, it has been pivotal in studies of adaptive radiation, ecological competition, and rapid evolutionary change. The widespread introduction of A. sagrei also offers insight into the mechanisms of invasive species success and the evolutionary consequences of range expansion. 

Although phylogenetically distant from A. cristatellus, both species independently evolved similar trunk-ground features—an example of convergent evolution driven by shared ecological pressures.

Anolis carolinensis, also known as the Green Anole, is a well-known mainland Anolis species native to the southeastern United States. It belongs to the trunk-crown ecomorph and is commonly observed on tree trunks, fences, and building walls. This lizard can change its color from bright green to brown, a trait associated with both camouflage and thermoregulation. Anolis carolinensis has long limbs and an elongated head, features typical of species adapted to vertical environments.

It holds a special place in reptilian research, as it was the first non-avian reptile to have its genome fully sequenced. This genomic breakthrough has provided key insights into vertebrate evolution, particularly in understanding the genetic relationships between reptiles, birds, and mammals.

Additionally, the green anole has become a model organism in urban ecology, with studies focusing on how it responds to habitat modification, human activity, and thermal variation in urban environments.