It’s time to vote for the best anole photos of 2012. We had an overwhelming response with more than 60 entries, most of them excellent. Our panel of experts slaved over the submissions to choose 24 semi-finalists. Decision criteria were the quality, crispness, and composition of the photo, as well as the species.
You can vote for up to 3 photos. Voting will end on October 31st, at the stroke of midnight.
That’s right, you heard it here first. Read all about it, including a great sequence of photos and the story behind it, at Daffodil’s Photo Blog. We’ve mentioned this site before, as it’s the site of anole lover and author Karen Cusick, who wrote Lizards on the Fence. If you check out her blog, you’ll see that there are regular posts on the antics of her backyard greens and browns. Worth a visit!
It’s been a good couple of years for studying lizard smarts. Last year, Manuel Leal demonstrated keen cognitive abilities in Anolis evermanni. More recently a couple of studies Down Under have shown that slippery Aussie skinks have a lot going on upstairs as well. Over at The Lizard Lab, Martin Whiting has just posted a nice review of these studies.
httpv://www.youtube.com/watch?v=LVdLNIXujL8
My vain attempt at alliteration with the title, here’s a news story on those pesky lizards mucking about with electrical power (sorry I don’t know how to avoid you watching the ad at the beginning).
From Dustracks on the Web.
Janson Jones has a binder full of anoles.
In the latest issue of Copeia, Eric Pianka provides the latest positive review of Lizards in an Evolutionary Tree. Its easy to understand why this review appears more than three years after the book’s publication when you remember that Pianka has been a busy dude who most recently gained attention for recovering from the dead. Anole Annals also has archived links to other reviews of the book for those interested.
Photographs from Jaime Palacio Sierra. We are currently reviewing reptiles from our home department and have doubts on two specimens captured by Jaime. can anyone help us confirm their taxonomic identities?
Colombian caribbean Anolis
Variation in the back patterns of Anolis sagrei in the Bahamas. From Calsbeek and Cox (2010).
Last year, we had a series of posts discussing the evolution of dorsal patterns of female anoles, as well as several studies that reported intrapopulation variation in female patterning. Why such variation should exist is a mystery, and studies on both A. humilis in Costa Rica and A. sagrei in the Bahamas failed to find evidence that natural selection was acting on this variation.
Now, Calsbeek and Cox report an experimental study of natural selection on dorsal pattern on small islands in the Bahamas. They introduced anoles with the three patterns shown on the left onto four small islands. Two of the islands had birds and snakes, the other two had neither. One predator-exclusion island was studied in 2008, the other three in 2009. In addition, the authors measured selection in a natural population over the course of four years.
The major result of the study is that not only was survival reduced on islands with predators, but also in the presence–but not absence–of predators, the intermediate diamond-bar pattern had higher survival than the other two patterns. How this intermediate pattern leads to heightened survival is not clear, and the authors propose a few hypotheses for future testing.
R. CALSBEEK & R.M. COX (2012). An experimental test of the role of predators in the maintenance of a genetically based polymorphism Journal of Evolutionary Biology DOI: 10.1111/j.1420-9101.2012.02589.x
Three weeks ago, I initiated discussion of Nicholson et al.’s recent monograph by noting that it is the most important paper on anoles published in recent years. We’ve had a lot of interesting discussion of many aspects of the paper since then, but we should keep in mind, even in the light of this discussion, that regardless of what one thinks about the various issues debated on our pages, this paper certainly represents a comprehensive compendium of knowledge about anole taxonomy, systematics, biogeography and ecology, and as such will remain an important resource for years to come.
Having said that, I wanted to use this last post of mine to synthesize what I see as the conclusions of the past three weeks’ discussion concerning the “bold hypothesis” of anole biogeography and evolution presented by Nicholson et al. Their hypothesis can be boiled down to three main points: Anolis is much older than previously recognized; divergence into eight major clades of anoles (which this paper raises to generic status) occurred when the geological blocks that now form the Caribbean islands separated from their previous, connected position where they had served as a landbridge connecting North and South America (and, hence, anole biogeography is primarily the result of vicariance, rather than dispersal); and the history of anole habitat use is primarily one of change from a large, crown-inhabiting species to smaller species found on or near the ground. How does this scenario stand up in light of discussion on AA?
Anolis Is Much Older Than Previously Recognized
Nicholson et al. conclude that the ancestor of anoles diverged from their nearest relative 95 million years ago (mya) and that diversification to produce the eight major clades occurred 72-87 mya. These dates are far older than other estimates; three recent studies have pegged the split between Anolis and its sister taxa as occurring 25-80 mya.
Nicholson et al. molecular phylogeny with their dates of divergence and with dates corrected assuming a younger date for the Mexican amber anole, A. electrum in parentheses. The arrow points to the phylogenetic position where A. electrum was placed by Nicholson et al.
This proposed antiquity of anoles is surprising, but is almost surely mistaken.
I have followed the controversy over anole classification with interest. Amphibian taxonomists faced a similar issue with the reclassification of Bufo and Rana, among many lesser-known genera. I discovered that most herpetologists quickly accept new taxonomies (with the exception of extreme and ill-founded taxonomies, like those proposed by Hoser). So attempts to resist will likely fail. However, there is an intermediate option that is being used successfully for some taxa and I think it could be profitably pursued for anoles. That is, use subgenera. In short, keep using Anolis as you have historically, but if you think the phylogenetic analysis of Nicholson et al. meets your standards of quality, treat their genera as subgenera. Anolis is the oldest valid taxon and so it has priority. I argue that the name Anolis (Dactyloa) latifrons is more informative taxonomically, phylogenetically and biogeographically than is the name Dactyloa latifrons. What are the arguments against using subgenera? I can think of none. I advocate doing this for Bufo and Rana (making certain that each is monophyletic, of course). The argument against this move is that some relatively well-known names of genera would be lost, but I do not think that is the case. For anoles nothing is lost if one uses subgenera. Subgenera are being used successfully for salamanders. Hydromantes is a well-known group of salamanders, admittedly small in relation to Anolis. It is clearly a clade based of substantial DNA sequence data and osteological-myological data. Yet some wanted to break it up because it occurred in Europe and North America. To me this is one of the best reasons for keeping it a single genus. So I have advocated a three-subgenera classification: Hydromantes (Hydromantes) for the American species and Hydromantes (Speleomantes) and Hydromantes (Atylodes) for the European species. This highlights the fact that Hydromantes is monophyletic (no-one questions this) and also reminds us of the extraordinary distribution. With colleagues I have proposed seven subgenera for the 121 species of Bolitoglossa, three subgenera for the 36 species of Oedipina, and two subgenera each for the 22 species of Batrachoseps and the 55 species of Plethodon.
Why not use subgenera for anoles?
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