Professor of Biology and Director of the Living Earth Collaborative at Washington University in Saint Louis. I've spent my entire professional career studying anoles and have discovered that the more I learn about anoles, the more I realize I don't know.
That’s right, it says so right here!
No surprise to us at AA, but greenies apparently provide yeoman service as garden pest control. And the wonderful folks at www.getmypestout. com provide all kinds of good advice about how to foster a healthy anole population in your garden. Good on ’em!
This NC green anole is on the ground, but mostly they apparently are up in the trees. Photo from http://www.wildherps.com/images/herps/standard/08041129PD_green_anole.jpg
We’ve had a lot of talk here on AA about how green anoles can be found low to the ground in places where A. sagrei has not invaded. But Manuel Leal says that’s not so in sagrei-less North Carolina, where all the ones he saw in the woods were high in the trees. What gives?
A recent photograph by Emma Sherratt. Amber tends to darken over time, which explains the deep orange color.
We’ve had previous posts on fossil anoles in amber. Emma Sherratt is currently studying them and has examined some three dozen specimens. All of these are from the Dominican Republic. Except the first one ever discovered, a Mexican piece described by Skip Lazell in 1965. Anolis electrum, as it was named, has had a pretty quiet scientific life. Now middle aged, the species has not been the subject of any subsequent research in the 47 years of its existence. But now it’s in the spotlight, as its phylogenetic position and dating may be pivotal for the recent calculation by Nicholson et al. that anoles originated more than 100 million years ago. In this post, I summarize what is known about A. electrum (examine the short original paper for yourself!). No doubt, we’ll be hearing more soon about the relevance of this species–specifically its phylogenetic placement and age–for dating anole diversification.
As you can see for yourself in the photo above, there are actually two pieces, a front half of a lizard and a back half a lizard. Since they were found together (or at least made it to the Paleontology Museum at UC-Berkeley together) and are matching in size, it seems like too much of a coincidence for them not to come from the same animal. Various aspects of the animal’s scalation are discernible, including some nicely visible toepads. Lazell stated that all that was left was skin, or the impression of skin, the bones having been eaten away, but Emma’s cat scanning has shown that this is not quite correct (see below).
Based on the specimen, what can be said about its phylogenetic placement? All anoles in Mexico today are from the Norops clade. Unfortunately, the primary character for identifying Norops is the shape of the caudal vertebrae, which cannot be discerned in this tailless specimen. Lazell compared the scalation of this specimen (a 26 mm juvenile) to various species, and found that the scalation was unlike most species. He concluded that electrum was most similar in scalation to A. fuscoauratus, A. maculiventris, and A. chloris, and among species found in Mexico, to A. limifrons (full quotations at the bottom of this post).
What should we make of all of this? It’s important to remember that this paper was published in 1965, prior to the description of many extant anole species and a year before Willi Hennig’s classic introduction to cladistic analysis was translated into English. This is a purely phenetic comparison of the amber baby lizard to known species, clearly non-phylogenetic and utilizing characters that now are recognized to generally have little higher level systematic utility in anoles. And the conclusion is that it is either a Norops clade anole (fuscoauratus, limifrons or maculiventris) or a Dactyloa species (chloris).
The other question one might have is: how old is this fossil? Dating amber is notoriously difficult. Solórzano Kraemer reviewed all of the data on Mexican amber bearing deposits in the 2010 volume Biodiversity of Fossils in Amber from the Major World Deposits and concluded: “In summary, it can be said that Mexican amber can be correlated with Dominican amber, with an age of approximately 15-20 million-years-old.” In other words, Mexican and Dominican amber anoles were contemporaneous.
Did anyone notice anything odd on the fossil of the lizard posterior (B, above)?
We’ve already received a lot of great entries, but there’s room for more! We’re reprinting the announcement below. Deadline is September 30, so submit today!
Last year we had an Anolis photo contest and produced a 2012 anole calendar. Both were wildly successful. Today, Anole Annals is pleased to announce it is combining both. We herewith announce the 2012 Anole Photo Contest. The goal of the contest is to identify 12 winning photos. The grand prize winner will have her/his photo featured on the front cover of the 2013 Anole Annals calendar and will receive an autographed copy of Karen Cusick’s lovely book, Lizards on the Fence. The second place winner will receive a copy of the calendar and have her/his photo featured on the backcover of the calendar.
The rules: please submit photos as attachments to anoleannals@gmail.com. To ensure that submissions with large attachments arrive, it’s a good idea to send an accompanying e-mail without any attachments that seeks confirmation of the photos receipt. Photos must be at least 150 dpi and print to a size of 11 x 17 inches. If you do not have experience resizing and color-correcting your images, the simplest thing to do is to submit the raw image files produced by your digital camera (or, for the luddites, a high quality digital scan of a printed image). If you elect to alter your own images, don’t forget that its always better to resize than to resample. Images with watermarks or other digital alterations that extend beyond color correction, sharpening and other basic editing will not be accepted. We are not going to deal with formal copyright law and ask only your permission to use your image for the calendar and related content on Anole Annals. We, in turn, agree that your images will never be used without attribution and that we will not profit financially from their use (nobody is going to make any money from the sale of these calendars because they’ll be available directly from the vendor).
Please provide a short description of the photo that includes: (1) the species name, (2) the location where the photo was taken, and (3) any other relevant information. Twelve winning photos will be selected by readers of Anole Annals from a set of 28 finalists chosen by the editors of Anole Annals. The grand prize winning and runner-up photos will be chosen by a panel of anole photography experts. Deadline for submission is September 30, 2012.
We’ve previously discussed cases of anoles being mistaken for geckos, as well as the very negative effects that cats can have on green anoles. Turns out that anoles aren’t the only lizards that serve as gecko doppelgangers. And you might think that people wouldn’t mistake lacertids for anoles, but apparently that happens, too.
We’ve had a week now to let the proposed reclassification of Anolis sink it, so it’s time to start discussing it. A revolutionary new view of the scientific review process suggests that in the future, all papers will be published open access online (as this one is–thanks Nicholson et al.), the journal in which it appears (if any) will not matter, and peer review and evaluation will be conducted post-publication on internet discussion sites. Realistic? Who knows, but why not give it a try?
The paper by Nicholson et al. is undoubtedly the most important paper on anoles to be published in the last several years. Not only does it propose to split Anolis into eight genera, but it also presents provocative findings about the ecological evolution of anoles (including throwing out the ecomorph concept), anole biogeography, and the dating of evolutionary events in anole history.
Anole Annals’ goal is to be the meeting place for discussion of all things Anolis, so let’s take this post-publication review and commentary idea out for a spin. Anole Annals invites members of the anole community to post their thoughts on any aspect of the Nicholson et al. paper. We hope to get a conversation going on the merits of splitting the genus, as well as the other issues raised in the paper. In fact, this has already begun, as evidenced by the comments by Mssrs. Crother, Hillis and Duellman, among others.
To get the ball rolling, here’s a short précis of the paper:
1. Phylogenetic analysis based on previously published data of all sorts (genetic, morphological, karyological), with a smidgeon of new molecular data, reveals a phylogeny with eight strongly supported clades in a Bayesian analysis. These clades are recognized as distinct genera.
2. The ecomorph concept does not apply to mainland anoles because species similar in habitat use are not similar in morphology. Hence the term “ecomode” is coined for species similar in habitat use. Phylogenetic analysis of ecomode evolution on the phylogeny suggests that the crown-giant ecomode is ancestral for Anolis. The ecomorph concept is argued to not work for Greater Antillean anoles and should be discarded.
3. Biogeography is reconstructed on the phylogeny. Using the phylogeny, the authors argue that the eight clades differentiated about the time that the proto-antillean islands were passing between what is now North and South America. The Norops clade differentiated on several of these blocks (both island and mainland), explaining why Norops is nested within Caribbean non-Norops taxa without requiring the island-to-mainland colonization of Norops proposed by a number of previous papers.
4. Molecular clock dating reveals that anoles are surprisingly ancient, originating in South America approximately 130 million years ago.
Nicholson, K. E., B. I. Crother, C. Guyer, J. M. Savage (2012). It is time for a new classification of anoles (Squamata: Dactyloidae) Zootaxa, 3477, 1-108
Photo by Jonathan Losos
I’ve just learned of a website called Atyourservices. I don’t understand the point of this site, which seems to have a disparate range of topics, but one of the posts today is a nice compilation of sources of photos and information on Anolis aequatorialis.
From http://blogs.scientificamerican.com/tetrapod-zoology/2012/09/17/amazing-social-life-of-green-iguana/
Here at Anole Annals, we occasionally digress to post on interesting topics in anole relatives. In that vein, I wish to call attention to a fascinating summary of the social complexity of Anolis‘s big green cousin, Iguana Iguana. Tetrapod Zoology, a fascinating source of information on all thing Tetrapodan, has a very interesting article which I highly recommend.
I’ll give one hint: it started something like this.
Those guys at Tropical Herping have done it again. Check out their new post with information and lovely photos of Anolis gemmosus, truly a gem of a lizard.
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