Lizard Model Organisms

Anolis Lizards
Anolis lizards are our primary model system. With nearly 400 species, Anolis represents the world’s most species-rich amniote genus. This diversity is most striking on Caribbean islands, where anoles have undergone remarkable adaptive radiations. On many islands, anoles are the most abundant and conspicious vertebrates, making them outstanding subjects for research. Research in our lab focuses primarily on the anoles found on the four large Greater Antillean islands (Cuba, Jamaica, Hispaniola, and Puerto Rico). It is on these islands that the anole radiation reaches its peak, with communities typically consisting of five or six species, and sometimes including as many as eleven ecologically and morphologically distinct forms. Because anole radiations have occurred indpendently on each island, anoles present a unique opportunity to conduct replicated tests of important evolutionary questions. One of our main goals is to take advantage of this replication via integrative, comparative analyses conducted across islands. For example, this approach has recently been used to show that speciation mechanisms and patterns of ecological specialization are often shared among independently diverging radiations. Although Greater Antillean anoles have been studied intensely for over thirty years, this work has raised more questions than it is resolved. Today, anoles are being studied by a highly interactive community of scientists who emphasize collaboration over competition (check out our community blog). Building from decades of previous study, our lab’s goal is to advance our understanding of anoles through the use of recently-available molecular markers and other developing resources such as museum and GIS databases. The recently completed whole genome sequencing project involving the green anole (Anolis carolinensis) is bringing investigations of this group to an entirely new level and provide exciting opportunities for many years to come.

anole_montage
Greater Antillean anoles (clockwise from top left): Anolis sagrei, one of Cuba's most common species that is now globally-distributed thanks to human introductions; Anolis vermiculatus, an aquatic species from western Cuba; Anolis barbatus, a strange Cuban species with molar-like teeth that feeds on snails; Anolis allisoni, another Cuban species that may be the most beautiful of all anoles; Anolis bartschi, a spectacular rock-dweller that lacks a dewlap; Anolis distichus, a remarkably polymorphic species from Hispaniola and the Bahamas; Anolis aliniger, a montane species from Hispaniola (center).

Sphaerodactylus Lizards
Sphaerodactylus is a genus of nearly 100 diminutive gecko species that includes the world’s smallest amniote (PDF).  Along with Anolis and Eleutherodactylus, sphaeros represent one of the three dominant components of West Indian herpetofauna in terms of abundance and species diversity.  Their species richness peaks on the Greater Antilles, where the majority of species are endemic to a single island.  On each of these large islands, sphaeros range from the coastal deserts to the top of mountains.  They are primarily semi-fossorial but a few species can be found several meters off ground, in bromeliads or rock crevices.  Although we know remarkably little about sphaeros, what is known suggests sphaeros are an excellent model system for ecological and evolutionary studies.  Because sphaeros have independently radiated within each Greater Antillean island, for example, they offer an opportunity to test whether patterns of speciation and ecological specialization are replicated, as they are in anoles.  We are testing for shared patterns of ecological diversification across islands, and with Anolis, with a variety of data – microhabitat quantifications, GIS-based climatological data, as well as physiological and morphometric data.

A, Sphaerodactylus difficilis male; B, S. plummeri male; C, S. thompsoni male; D, S. ocoae female; E, S. ariasae adult male - the smallest amniote species; F, S. schuberti juvenile; G, S. cochranae female; H, S. leucaster female; I, La Muñeca de Piticabo - A stuffed animal denotes the trail to the type locality of S. ariasae on the southern most point of Hispaniola.  The absurdity of the scenery is only matched by the absurdity of the quest.; J, Palm trash habitat of S. difficilis and representative of other coastal Sphaerodactylus; K, Wasps nests are commonly encountered while collecting Sphaerodactylus.
A, Sphaerodactylus difficilis male; B, S. plummeri male; C, S. thompsoni male; D, S. ocoae female; E, S. ariasae adult male - the smallest amniote species; F, S. schuberti juvenile; G, S. cochranae female; H, S. leucaster female; I, La Muñeca de Piticabo - A stuffed animal denotes the trail to the type locality of S. ariasae on the southern most point of Hispaniola. The absurdity of the scenery is only matched by the absurdity of the quest.; J, Palm trash habitat of S. difficilis and representative of other coastal Sphaerodactylus; K, Wasps nests are commonly encountered while collecting Sphaerodactylus.

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