*Article* **Biogeography, Systematics, and Ecomorphology of Pacific Island Anoles**

**John G. Phillips 1,2,\*, Sarah E. Burton 1,3, Margarita M. Womack 4, Evan Pulver 1,5 and Kirsten E. Nicholson 1**


Received: 1 July 2019; Accepted: 15 August 2019; Published: 21 August 2019

**Abstract:** Anoles are regarded as important models for understanding dynamic processes in ecology and evolution. Most work on this group has focused on species in the Caribbean Sea, and recently in mainland South and Central America. However, the Eastern Tropical Pacific (ETP) is home to seven species of anoles from three unique islands (Islas Cocos, Gorgona, and Malpelo) that have been largely overlooked. Four of these species are endemic to single islands (*Norops townsendi* on Isla Cocos, *Dactyloa agassizi* on Isla Malpelo, *D. gorgonae* and *N. medemi* on Isla Gorgona). Herein, we present a phylogenetic analysis of anoles from these islands in light of the greater anole phylogeny to estimate the timing of divergence from mainland lineages for each species. We find that two species of solitary anoles (*D. agassizi* and *N. townsendi*) diverged from mainland ancestors prior to the emergence of their respective islands. We also present population-wide morphological data suggesting that both display sexual size dimorphism, similar to single-island endemics in the Caribbean. All lineages on Isla Gorgona likely arose during past connections with South America, and ecologically partition their habitat. Finally, we highlight the importance of conservation of these species and island fauna in general.

**Keywords:** Dactyloidae; ecomorphology; Iguania; Isla Cocos; Isla Gorgona; Isla Malpelo; island biogeography; lizards; neotropics; overwater dispersal
