Author: Rich Glor Page 5 of 13

Photo by Claus Meyer at http://www.nationalgeographicstock.com/

For many years, the South American lizard genus Polychrus has been considered the closest extant outgroup to Anolis.  In light of this phylogenetic position, the authors of a new report on the life history of Polychrus acutirostris note that “a comprehensive understanding of Polychrus might help clarify possible ecological factors related to the radiation of anoline lizards as well as to infer the existence of niche conservatism or dietary shifts related to the origin of this large lizard radiation” (Garda et al. 2012).

Members of Polychrus are superficially similar to Anolis, and are mostly medium sized arboreal and diurnal lizards.  However, Polychrus also differs from Anolis in both conspicuous (e.g., lack of toepads) and somewhat less conspicuous ways (e.g., its tendency to produce single clutches of multiple eggs, versus multiple one egg clutches in Anolis).  In their report, Garda et al. (2012) compare populations of Polychrus acutirostris found in two different Brazilian habitats to test whether size of eggs and clutch size, reproductive seasonality, diet, and size of reproductive adults varies among populations in the manner predicted by life history theory.  Although recent work makes Polychrus‘s position as the outgroup to Anolis less certain than it once was (Schulte et al. 2003, Townsend et al. 2011, and this previous AA post), we still have much to learn from the type of comparative studies that Garda et al. have implemented.

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Another week brings another nice batch of anole publications from a few previously held meetings. This batch comes from a combined special issue of General and Comparative Endocrinology that features articles from The Inaugural Meeting of the North American Society for Comparative Endocrinology (NASCE) and the 7th International Symposium on Amphibian and Reptilian Endocrinology and Neurobiology (ISAREN) held last July.  The papers from this meeting are now available at the journal’s page at Elsevier ScienceDirect.

Wade (2012) provides a nice review of structure and function of three sexually dimorphic anole features in green anoles (Anolis carolinensis): the forebrain, the dewlap neuromuscular system, and the copulatory neuromuscular system.  She also reviews comparative studies across anole species of the dewlap system and provides a detailed discussion of endocrine regulation in green anoles.  Cohen & Wade (2012) investigated “Aromatase and 5 alpha-reductase type 2 mRNA in the green anole forebrain: An investigation of the effects of sex, season and testosterone manipulation.”  Finally, in a non-anole paper about other iguanid lizards Hews et al. (2012) investigate “neuroendocrine correlates of aggression differences in adults of two Sceloporus lizard species.”

As reported previously at Anole Annals, The 2012 meeting of the Society of Integrative and Comparative Biologists (SICB) was packed with anoles (1, 2, 3, 4, 5, 6).  At least 17 talks or posters mention Anolis in title (complete list below the fold)!  The abstracts from this meeting are now available via PDF from the Society’s journal Integrative and Comparative Biology.  I was excited to see all of the new anole content as it appeared on Web of Science and other indexes, but disappointed that these titles were only associated with abstracts.  To all of you who presented: please get this stuff published, many of your titles are very compelling and the anole community can’t wait to learn more!

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It’s immediately clear to anyone visiting the Greater Antilles that humans have had a dramatic impact on natural environments.  Even in those areas that remain forested and seemingly pristine, it isn’t difficult to find the stray coffee bush or mango tree.  Indeed, some understory crops, such as coffee and cacao, have traditionally been grown under an intact canopy.  These traditional practices have been changing over the past few decades, however, as large commercial operations have favored the efficiency of clear-cutting and subsequent cultivation in open sun.  The impacts of this shift from shade to sun cultivation on biodiversity have been debated for decades, with most studies indicating overall losses in biodiversity and super-abundance of a few common species in sun plantations.

In spite of the prevalence of agriculture in the Greater Antilles, relatively few studies have investigated the abundance of anoles and other lizards in different types of agriculturally disturbed habits (but see my first first authored paper!).  A new study by Borkhataria et al. (2012) conducts a comparative analysis of species abundance of birds, anoles, and invertebrates in shade versus sun coffee on Puerto Rico.  This study is a welcome addition to the literature because the portion of coffee on Puerto Rico grown in sun plantations has doubled in recent years, although overall coffee production has declined.

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Few anole species have been responsible for as much taxonomic confusion as the widespread Amazonian species Anolis chrysolepis.  It wasn’t even until 2008 that taxonomists decided once and for all that this species should be called A. chrysolepis (Duméril & Bibron 1837), rather than A. nitens (Wagler 1830) (Mayer 2008 successfully petitioned for recognition of  A. chrysolepis on the grounds that Wagler’s Draconura nitens was a nomen dubium due to the absence of a holotype and an exceptionally vague 4-line description and locality [“America”]).

Largely because of its broad range and remarkable geographic variation in size, shape, and coloration, Anolis chrysolepis has attracted the attention of herpetologists for generations.  

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The University of Chicago Press has recently published another outstanding new book for comparative biologists.  Charles Nunn‘s The Comparative Approach in Evolutionary Anthropology and Biology provides insightful reviews of methods for ancestral character reconstruction, phylogenetic tests for character correlation, phylogenetic diversification analyses, and many other topics.  Nunn’s book seems well-suited to a broad range of readers.  It seems tractable for novices (the second chapter explains what a phylogenetic tree is), and those with math anxiety won’t be deterred by dense discussions of mathematical or computational algorithms.  At the same time, seasoned comparative biologists will likely appreciated Nunn’s fairly comprehensive coverage of alternative methods and their relative strengths and weaknesses.  Although most of Nunn’s examples are from anthropology, the general lessons in this book are likely to be of interest to many anole biologists and the examples from anthropology are often insightful and thought provoking.  To top it all off, the book is accompanied by really nice webpage called AnthroTree that features tutorials and worked examples.