Anole Annals

Anolis ginaelisae

Six large anoles of the Dactyloa clade occur in western Panama. In their explorations, Lotzkat and colleagues have collected all of them, and have just published a paper in Zootaxa reviewing these species. Their phylogenetic analyses based both on DNA and morphological characters confirm the existence of the six taxa, but also find geographically-oriented genetic differentiation in two species. In combination with morphological data, the authors split A. microtus into two species, the new one under the name A. ginaelisae.

The paper includes a nice review of all the species including spiffy color plates (see A. ibanezi below as an example) and natural history notes (short take: they’re all arboreal and almost all individuals have been caught at night). A key is also included.

Anolis ibanezi

One last note. The derivation of the new specific epithet gianaelisae is touching: “Sebastian Lotzkat dedicates this exceptionally beautiful new species to his even more enchanting fiancée Gina Elisa Moog, who has made more than a third of his life worthwhile by now, in deepest gratitude for that wonderful time and pleasant anticipation of a mutual future.”

Abstract: “Six species of giant alpha anoles of the genus Dactyloa are known to occur in western Panama: Dactyloa casildae, D. frenata, D. ibanezi, D. insignis, D. kunayalae, and D. microtus. Based on own material collected along the highlands in Bocas del Toro, Chiriquí, and Veraguas provinces and the Comarca Ngöbe-Buglé of western Panama, we review their variation in morphological characters and the 16S rRNA mitochondrial gene. Our results support all six nominal taxa, but reveal considerable genetic differentiation between populations of the two highland species, D. casildae and D. microtus, respectively, from different localities. Correlated morphological differences confirm the existence of a cryptic species among populations currently assigned to D. microtus, which we describe as Dactyloa ginaelisae sp. nov. We provide point distribution maps, morphology and color descriptions, photographs in life, conservation status assessments, and an identification key for all seven species.”

Anolis homolechis

From 2009, we have investigated the evolution and ecology of Anolis lizards in Cuba, collaborating with Habana University and The National Museum and Natural History of Cuba. Prof. Losos asked us to describe our research projects in Cuba for communication among anole biologists. Thus, we would like to inform our ongoing projects on Anolis lizards in Cuba, and we are very grateful if you have any suggestions and comments on our projects. Also, your suggestion of collaborating research projects will be welcome.

1. Searching for the genetic basis determining differences in hindlimb length between the trunk-ground anole A. sagrei and the twig anole A. angusticeps. Similar to Sanger et al. (2012), we have tried to determine the developmental timing for divergence of hindlimb length between twig and trunk-ground anoles. The manuscript on this subject was submitted and is now under review.

2.  The effects of microhabitat use, range expansion and the number of speciation events on local species richness of trunk-ground Anolis lizards in Cuba. We examined the species richness and thermal microhabitat partitioning (considered to be a measure of ecological interaction) of 12 trunk-ground anole species in 11 local assemblages in Cuba, covering nearly the entire geographic range of all these species. Our results suggest that the species composition and richness in local assemblages could be explained by both evolutionary history (the number of speciation events and limits to range expansion) and ecological processes (habitat partitioning). This research is a part of Ph.D. thesis of Antonio Cadiz (Tohoku University and Havana University). The manuscript on this subject was accepted by Ecosphere and will be available soon.

3. We reconstructed a phylogeny using almost all Cuban Anolis lizards and also analyzed the genetic distances between populations within Cuban islands for these species. This project aims not only to construct the comprehensive phylogeny, but to understand ecomorph evolution within Cuban island.

4. Genetic basis for adaptation to different thermal environments. Multiple trunk-ground species can coexist since they inhabit different thermal environments. Anolis sagrei was found in open locations with high levels of light intensity and temperature. In contrast, A. allogus was found in shaded locations within forests with low levels of both light and temperature. Anolis homolechis was typically found at the edges of forests or in open locations in forests with intermediate environmental conditions. We try to examine genetic basis for these different thermal adaptation by using both  a candidate gene approach and whole transcriptome analysis.

5. Other research projects will be started this year, although we do not specify the detailed plan.

In addition to Cuban Anoles, we are investigating the evolution of Anolis carolinensis introduced into the Bonin islands (Ogasawara islands) about 50 years ago (from either Guam, Hawaii or Florida).

Masakado Kawata, Graduate School of Life Sciences, Tohoku University, Sendai, Japan (kawata ‘at’ m.tohoku.ac.jp)

The Puerto Rican Racer, Alsophis portoricensis. Photo by Donald Gudehus

Sometimes it’s easy to forget that anoles aren’t the only animals in the Caribbean. But, in fact, there are other types, even of reptiles, and some of them have diversified a fair bit (though none, of course, to the extent of anoles). One such group are the alsophiine snakes, formerly all in the genus Alsophis. This Caribbean radiation of racer-like snakes includes at least 43 species ranging in size from 200-2000 mm in length and occupying a variety of habitats.

Recently, Frank Burbrink and colleagues, in a paper in  the Journal of Biogeography, have re-analyzed DNA data originally presented by Hedges et al. and have investigated rates of species, morphological and ecological diversification. The phylogenetic tree they recover is very similar to the Hedges et al. phylogeny and indicates fairly extensive within-island diversification. Sounds very anole-like, but it turns out that rate of diversification is quite different. Unlike anoles, species diversification and the evolution of morphological variety putter along a fairly constant rate (with a few statistical twists and turns).

Why the difference? Burbrink et al. postulate that the opportunity for diversification has been just as great for alsophiines as for anoles, so why are the evolutionary patterns different? The authors put forward a number of possible explanations, but none is compelling. Of course, although adaptive radiations often exhibit explosive bursts of diversification, there is no necessity for this to occur, and some very diverse groups have radiated at a more sedate pace. Moreover, one might question why alsophiines haven’t diversified even more–sure, they differ in body size and climatic niche, but how different are they otherwise? And how many species can co-occur at a given locality? Is it just lack of time–one of Burbrink et al.’s hypotheses–or is something constraining alsophiine diversification?

More generally, it would be interesting to conduct similar analyses on other Caribbean taxa–not just reptiles, but also amphibians, birds, even insects and plants–to see what generalities, if any, characterize Caribbean evolutionary diversification.