Year: 2011 Page 21 of 42

A time calibrated tree from Townsend et al. and photographs of Polychrus (from http://reptile-database.reptarium.cz/species.php?genus=Polychrus&species=gutturosus), Anolis, and Basiliscus (from http://scienceblogs.com/tetrapodzoology/2009/01/something_new_about_basilisks.php)..

For decades, anole have been assigned to Polychrotidae, a family or subfamily of Iguania whose core members have always included Anolis and Polychrus. In spite of the morphological similarities shared by these genera, molecular studies conducted over the past decade have consistently recovered a non-monophyletic Polychrotidae and have never recovered strong support for a sister relationship between Polychrus and Anolis. In recent Bayesian and maximum likelihood analyses of 29 loci sampled from 47 iguanians and 29 outgroup taxa, Townsend et al. (2011) drive the final nail in the coffin of the notion that Anolis and Polychrus are closely related and form a clade that should continue to be recognized as Polychrotidae. The sister-group relationship between Anolis and Polychrus is completely absent from the posterior distribution of trees generated from Townsend et al.’s 29-locus concatenated dataset and this relationship appears in only one or two of their 29 single-gene trees. As a result, Townsend et al. limit Polycrhotidae to Polychrus and resurrect the family name Dactyloidae for Anolis. Although they acknowledge that Dactyloidae is a less intuitive name for this clade than Anolidae, the latter is junior synonym of the former, having been coined by Cope (1864) some 20 years after Fitzinger (1843) recognized Dactyloidae. Students of squamate phylogenetic systematics should definitely check this paper out, Townsend et al.’s results concerning Polychrotidae are only one of their many interesting insights.

Hedges Team Rediscovers Anolis darlingtoni

By Rich Glor

On August 2, 2011

In Anoles and Anolologists in the News, Natural History Observations, New Research, Notes from the Field

Image of Anolis darlingtoni from http://www.philly.com/philly/blogs/evolution/A-Long-Lost-Lizard-is-Found-in-Haiti.html

Last week, Blair Hedges led a team of scientists, journalists and naturalists on a helicopter tour of some of the most remote forested habitats remaining on Haiti’s Tiburon Peninsula. For anole enthusiasts, this expedition’s most remarkable find was the rediscovery of Anolis darlingtoni, an enigmatic species that hasn’t been seen since 1984. As reported by Faye Flam at Philly.com, expedition member Miguel Landestoy spotted a single animal sleeping around 2m up in a tree fern. This seems to have been the only darlingtoni recovered by the expedition, but full trip details are still filtering in.

Even with this rediscovery, Anolis darlingtoni remains the rarest anole on Hispaniola, and the one that is the most immediate danger of extinction. Luke Mahler and I went to a great deal of trouble to search for A. darlingtoni in remnant forests at the western end of the Tiburon Peninsula a few years ago and came up empty, so I know that finding this species is no easy feat. My congratulations to Blair, Miguel, and the rest of the team!

The Good Life For Green Anoles: Where No Browns Occur

By Jonathan Losos

On August 2, 2011

In Natural History Observations

Brown phase green anole. Photo by Janson Jones at Dust Tracks on the Web (http://dusttracks.com/)

At Dust Tracks on the Web, Janson Jones posts some interesting observations on green anoles (A. carolinensis) in northern Florida and southern Georgia, where the brown anole (A. sagrei) has yet to invade. To cut to the chase, he finds the green anoles to be larger, to be brown more often, and to perch much lower than green anoles do in central Florida in the presence of brown anoles.

The effect of brown anoles on greens in Florida has been surprisingly poorly documented. Just as surprisingly, very little information exists in the scientific literature on the habitat use, behavior, and other aspects of green anole natural history in places where they occur by themselves. We have almost no useful data on what green anole biology was like in Florida pre-sagrei, nor few data from areas where sagrei does not occur today. Detailed and quantitative studies of such populations would be particularly useful, as well as repeated surveys through time in areas that brown anoles may eventually invade to document what happens when they get there (of course, repeated surveys in areas that brown anoles don’t invade would be important to, as controls). Those of you who live in appropriate areas, get to it!

Anole Annals Challenge: Create a New Dewlap Collage

By Rich Glor

On August 1, 2011

In All Posts, Ask the Experts

Over the years, many talks on anole dewlaps have featured an image from Nicholson et al.’s 2007 paper from PLoS One on anole dewlap evolution (I saw this image at least once at JMIH this year). Now that its been almost five years since this image was published, I think its time we came up with a new collage of anole dewlaps. Which dewlaps should we include? Who’s got dewlap photos to share for the effort? If you’ve got some nice photos to share for the collage please post them here at Anole Annals and I’ll put them all together to generate our anole community dewlap collage! See the guidelines for posting for instructions on how to post images as part of a comment. (For my part, I’ve accumulated lots of photos from the Greater Antilles, but have almost nothing from the mainland or the Lesser Antilles.)

The Principle of Unsympathetic Magic Strikes Again

By Jonathan Losos

On July 31, 2011

In Natural History Observations

Who knows what Phenacosaurus dreams about?

On her very first day of anole fieldwork, soon-to-be graduate student Katie B. experienced a clear example of the wisdom of Ernest Williams. Out at night looking for anoles with her soon-to-be advisor, they came across the first Phenacosaurus orcesi of the trip, clinging to a narrow, vertical twig about eight feet above the ground. This led to a long pontification by the advisor on how some anoles sleep on leaves, others on branches, and so on, but how P. orcesi, in so many respects similar to twig anoles, would surely only be found sleeping on the twigs to which it is so well adapted, and would abjure all vegetated slumber sites. Needless to say, the next phenacosaur found that evening was snoozing sprawled across a leaf (as well as the next one found the following evening), teaching Katie both about the Principle of Unsympathetic Magic and the general lack of veracity of anything her advisor-to-be says.

p.s. Katie won the candy bar for correctly predicting the number of lizards captured on the first evening.

Orange sagrei

By Sean Giery

On July 29, 2011

In Introduced Anoles, Natural History Observations, Notes from the Field

I saw the recent posts about orange/red sagrei and I thought I might contribute another observation of orange-colored brown anoles. A few years ago while assisting another grad student with his dissertation work I spotted a few orange-colored brown anoles in a suburban yard in S. Florida. What I thought was most interesting about the observation was that: 1) there were multiple males (2-3) with orange color, and 2) many of the palms on which lizards were perched were a similar orange color. It got me thinking that it could be more than a coincidence.

The orange color on the trees, sidewalks, and other hard substrates in the area is from ground water with a high concentration of iron. When sprayed on the surface with sprinklers it mixes with oxygen and leaves an orange color. Many houses, signs, sidewalks, and even cars in S. Florida are graced with an arc or two of orange residue. I’ve yet to revisit this lawn or surrounding houses, but I bet there are quite a few more houses with orange lizards. For what it’s worth, I see and catch a lot of brown anoles further south in the Miami area and this is the only case of red/orange brown anoles I’ve seen yet. It’s possible that these lizards were covered in rust, but it didn’t look like it when I got one in my hand. It’s also interesting that all of the photos I’ve seen of orange-colored brown anoles are male, however I’ve only seen about 4 cases including this observation. Oh, and the dewlaps on these males were normal(ish), not like the cool one recently posted by Joe Burgess.

In Quest of Phenacosaurus

By Jonathan Losos

On July 29, 2011

In Notes from the Field

Phenacosaurus heterodermus (photo from http://www.flickr.com/photos/sngcanary/4207771662/)

“Among the strange and varied production of the high Andes is a small assemblage of grotesque, big-headed, short-legged, prehensile-tailed lizards: the genus Phenacosaurus.”

So starts Skip Lazell’s (1969) taxonomic revision of the three species in the anoline genus Phenacosaurus. Since that time, there have really been only two developments in phenac world. First, phylogenetic studies have conclusively demonstrated that phenacosaurs represent an evolutionary offshoot within the Dactyloa clade of anoles. As a result, most systematists now consider these species to be members of the genus Anolis, though some diehard romantics/heretics still use Phenacosaurus. Second, the last 40 years have seen a veritable phenaco-population explosion, with 11 species now recognized, and word on the street that more are on the way.

Despite these advances, our knowledge of phenacosaur biology has barely budged since Lazell’s time.

Anole Genome Research: New Primers for All!

By Rich Glor

On July 28, 2011

In Anole Genome Research, New Research

Table from Portik et al.'s Conservation Genetics paper reporting new primer pairs for amplification of nuclear loci (left side) and a phylogeny generated using some of these loci from Stanley et al.s' 2011 MPE paper on cordylids (right panel).

A new study by Portik et al. used the anole genome to develop more than 100 new primer pairs for the amplification of nuclear-encoded DNA from squamates, some of which have already proven useful for inferring relationships within and among species. Portik et al.’s carefully thought out strategy for marker development – which focused on rapidly evolving protein-coding loci – ensures that their loci will be particularly useful for phylogenetic analyses. First, Portik et al. focused on intronless protein-coding genes, with the goal of limiting length variation and simplifying alignment. Second, recognizing low variability relative to non-coding regions as a potential limitation of protein-coding loci, Portik et al. focused exclusively on developing markers from loci that are more variable than the first third of RAG-1 (one of the most useful and widely-used of the nuclear genes used previous phylogenetic studies of squamates). This strategy yielded 104 genes and led to development of primers for 170 gene fragments ranging from 407-2,492 bp. Portik et al. conducted limited PCR testing on 70 of these loci and found varying degrees of success across five squamate families, including Scincidae, Varanidae, Agamidae, Cordylidae, and Gekkonidae. More importantly, some of the loci have already proven useful for phylogenetic studies of skinks (Portik et al. 2010 , Portik et al. 2011), cordylids (Stanley et al. 2011) and iguanids (anole genome paper, which is currently in press at Nature).

While high throughput sequencing technology will eventually render PCR primers and Sanger sequencing nothing more than curiosities from a previous generation, this time is at least a few years away. In the meantime, Portik et al. have given the herpetological community some very useful new tools to play with.

Competition, Predation, and Selection: The Usefulness of Scientific Debate

By Adam Algar

On July 26, 2011

In New Research

Kidd Cay, one of the islands included in the Calsbeek and Cox (2010) study (photo from Losos and Pringle, 2011).

Chances are that if you read this blog, then you also tend to note when Nature publishes something anoley. Thus, you’re probably already aware that last week Losos and Pringle published a reply to a paper by Calsbeek and Cox that appeared in Nature last year. In that paper, C&C concluded that competition is a more important agent of selection than predation for island anoles. In their reply, L&P point out limitations in the original study’s major assumptions, experimental design, and statistical analyses. Rather than go into all the gory details, I suggest you look at their reply directly. Just don’t let your non-anolologist colleagues or family members get a look at their Fig. 1a or you’ll lose any credibility you might have once garnered by speaking about the rigours of field work. As is usual, C&C have also published a reply to the reply where they respond to the criticisms, re-performing some analyses. Again, I don’t want to focus on the details; I’d rather let each reader decide for themselves.

Personally, I enjoy reading replies and replies to replies and if it gets to a reply to a reply to a reply, well even better! It’s the way science should work – someone publishes something, there is debate, and the scientific community self-corrects if necessary. However, recently an article in Ecosphere entitled “Do rebuttals affect future science?” by Banobi et al. challenged this view.

Carolinensis – Sagrei Hanky Panky

By Jonathan Losos

On July 25, 2011

In Natural History Observations

Those rascals! I’ve heard reports of this before, but never seen a photo. I wonder if it’s always a male green anole, or whether both ways occur. In any case, it would be shocking if such liaisons led to the production of hybrid offspring, given that the two species belong to evolutionary lineages that separated many many millions of years ago.