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Quick—when you think of an agitated anole, what’s the first thing that comes to mind? Perhaps a quick color change, maybe even some squeaking and biting and, of course, a couple flashes of the dewlap all may have been high on the list. Well, not to be outdone by its cousins from the new world, the Middle-eastern yellow-spotted Agama (Trapelus flavimaculatus)  has come up with a spectacular display that involves all three behaviors listed above.

Now while its true that when it comes to agamid dewlaps, this species is not as well endowed as a few others (Hypsilurus and Draco come to mind), no other agamid (to my knowledge, that is) displays quite like it. First off, the lizard changes  from its usual drab brown coloration (essential for a desert dwelling lizard)  to a  light cobalt blue while its ordinarily pale yellow tail glows neon orange. Next, the lizard opens its mouth and displays the bright orange inside of its jaws while making a hissing noise.

The final act to this performance comes when the lizard extends its deep cobalt blue dewlap at the attacker. As soon as the threat is gone, the display is over and the lizard resumes its usual coloration. These lizards also use this display as a means of attracting/advertising their presence to females, so that’s another thing they might have in common with Anolis (I’m not exactly sure if the Anolis dewlap actually helps attract females). I thing it’s interesting that while anoles turn darker to convey agitation, these lizards actually become brighter. I think this has something to do with the fact that these are desert lizards and the blue color is really more in contrast to the desert  environment.

On a related note, how many other lizards out there have the ability to change color based on their mood?

Everyone (who reads this blog) knows that anoles are one of the most fascinating groups of organisms on the planet. We also all know that this makes them a remarkably popular lizard genus to study, a topic that Rich Glor has addressed on this blog previously. However, while dominant in some fields (and meetings, like Evolution or SICB) anoles scarcely make an appearance at others (ESA, IBS). This raises the question of whether anoles are really as popular as we think? How do they stack up to other sexy taxonomic groups like mammals, birds or bees?

A recent tweet and blog post by Chris Buddle from McGill gives the basis for an answer. He used a (quick and dirty) Web of Science search to find the number of publications per species within 15 haphazardly chosen Orders, merging these into higher taxonomic groups for visual comparison:

Buddle showed that research publications are strongly biased toward mammals (no surprise there), then herps, then birds (I admit, a priori, I thought 2nd and 3rd would be reversed). However, the obvious question which jumped to my mind (and, I’m sure, to yours) was: how do our favourite dewlapping demons compare? A quick search on Web of Science with search string ‘Anole OR Anolis’ (yes I could have gone with anol*, but this picked up a few thousand extra hits for anolyte) gave approximately 12,686 hits. Using The Reptile Database‘s number of 393 anole species (cue argument now), I roughly mapped the anole results on to Buddle’s plot:

Anoles win! Perhaps not surprisingly, anoles are remarkably well studied given their diversity, at least compared to other groups defined at the Order level (keep in mind that, because publication intensity is uneven within taxa, averaging across a more diverse group will tend lower the numbers). Nonetheless, anoles annihilate the carnivores, which Buddle highlights as the most studied order with a publication to species ratio of 7. However, let’s not forget that the vast majority of these studies are on sagrei or carolinensis, so there are still hundreds of under-studied anoles (and really, can a species be over-studied?)

Lastly, before we get too smug about the popularity of our exalted study genus, with its publication to species ratio (pub:spp) of 32.3, I did a quick look at the numbers for the genus Parus. This genus (even after lumping it in with Poecile, Cyanistes, Lophophanes, and Periparus) had a pub:spp = 327.1. And within the herps? Well, Sceloporus clocks in at 85.7. And Xenopus‘ pub:spp is 12451.3! Of course, Xenopus’ ratio is heavily influenced by biomedical research. Also, as I mentioned above, the uneven study of species within genera means averaging over a diverse genus like anoles will drag down the ratio, compared to less diverse genera like Parus, Sceloporus, or Xenopus. Even so, while anoles are clearly very popular, we undoubtedly still have a lot of work still to do.

In flipping through field guides to look at agamid dewlaps, I came across a couple of South-East Asian Agamid lizards with blue eyes. Given our recent discussions of blue-eyed anoles, I thought I’d point out these lizards as well. All information is from L. Lee Grismer’s Lizards of Peninsular Malaysia, Singapore, and their Adjacent Archipelagos
(and here’s an AA review of the book).

Aphaniotis fusca (Dusky/Peninsular Earless Agama): more fascinating than the blue eyes themselves is the variation among individuals in iris colour–A. fusca irises can be blue, orange, or brown. It appears that blue irises are restricted to adult males, but not all adult males have blue eyes. Further, the inside of these lizards’ mouths (the oral mucosa, to be precise) are also bright blue, similar to  Anolis onca.

Gonocephalus liogaster (Orange-Ringed Anglehead Lizard): hands-down winner for lizard with the most dramatic eyes, adult males of this species have a bright blue iris surrounded by a bright orange ring.

 

With nearly 500 votes cast, it’s coming down to the wire. Get your vote in before the Sunday, 6 p.m. deadline!

All of us that observe and study Anolis (and Sitana) know that dewlaps make our favourite lizards special. Dewlaps can be key for species identification, and we pay a lot of attention to variation in their size and colour. But what exactly constitutes a dewlap?

I’m currently compiling a list of all lizard species with dewlaps, and have run into the problem of how to define a dewlap. Our trusted friend Wikipedia defines a dewlap thus:  a longitudinal flap of skin that hangs beneath the lower jaw or neck of many vertebrates. Helpful, perhaps, but only slightly, as the difference between a small dewlap and a puffed-out throat is not always obvious.

So we’re turning to you, dear reader, to help us figure out what a dewlap is. I think the easiest way to do so is by showing you a number of pictures of lizards and asking you to deliver a verdict on whether these lizards are in fact dewlapped (photos from various internet sources). Feel free to offer an alternative definition also, if you’d like.

1. Rock Agama

 

 

 

 

 

2. Calotes calotes from Sri Lanka

 

 

 

 

 

 

 

 

3. Panther chameleon

 

 

 

 

 

 

 

4. Varanus griseus

 

 

 

 

 

 

5. Iguana iguana

I’m currently preparing a grant proposal featuring Anolis sagrei for a philanthropic foundation with broad goals that extend well beyond biology. The people reading this proposal will thus have diverse backgrounds, probably mostly non-biological and certainly non-herpetological. In reading a draft of the proposal, a friend remarked “This lizard needs a new name for this grant!” And, indeed, on reflection perhaps “brown anole” is not the most exciting name for the general public.

So, who wants to help re-brand A. sagrei? Of course, an obvious possibility is Sagra’s Anole, since the species was, after all, named after Mssr. Ramon de la Sagra*. But…that’s not really that exciting either. My friend (a biologist) suggested “the tramp anole,” using “tramp” in the ecological sense of a weedy species that is able to colonize and establish in a wide variety of habitats. A possibility, for sure, but maybe some of the other connotations aren’t so good. His second suggestion, though,  merit’s consideration. Turns out that “sagre” in Italian means “a festival.” And what lizard could be more of a partier than the ever-flashing, always rollicking, A. sagrei? So, I put it to you, anole world, what if we start referring to this species as “the festive anole”?

*It’s an interesting story how the species ended up A. sagrei, and not A. sagrai, but that’s a tale for another time.

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And if you order by 9 p.m. eastern time today, it’s 31% off! Use this code: HALLOWEENDAY

Greetings to the Anole Annals community,

I love anoles and spend a lot of time wishing that I could personally observe the cornucopia of species that the world  has to offer, though not being a scientist by profession and only encountering a small number of anole species in my immediate vicinity, I am limited to finding all about anoles that I can  and trying my best to explain any interesting patterns that I notice, which brings me to the subject of this post.
On Jamaica, the island where I currently reside, there are seven species of anole lizards. However, only two of these, A. grahami and A. lineatopus, have an island-wide distribution  and, more importantly, they are the only two which occur with great frequency in urban areas of south-eastern Jamaica, so naturally when I first began catching anoles these guys were my most frequent quarry. My surprise came while I was holding a large, freshly noosed grahami, which I soon discovered is not among the list of creatures that readily accept being caught. In addition to thrashing wildly and making several futile attempts to do whatever damage it could with its diminutive teeth, the lizard let out a high-pitched squeak, sort of like a rubber duck being stepped on; this was so surprising to me that I immediately flung the lizard away and was left to watch as he scrambled away, no doubt feeling pretty good about his completely accidental victory.

It didn’t take me a lot of searching on the web to find out that vocalizations had been recorded for other species of anoles before, and so I decided to compile a list of every species that I could find for which there was any record of them vocalizing; so, for anyone who has ever wondered, here it is:

• All the cybotoids  (A. cybotes and relatives)
• A. garmani, A. valencienni, A. opalinus, A. grahami
• A. biporcatus, A. petersi, A. salvini (synonymous with A. vociferans)
•  A.roquet, A. trinitatis, A. extremus
• A. chocorum
• A. chlorocyanus , A. coelestinus, A. vermiculatus, A. hendersoni     
• A.occultus  

The list is immediately confounding in that there are at least three species groups up there (the grahami, hendersoni and roquet groups) in which all species are very closely related, but only some species vocalize; why is this ability popping up so inconsistently? I don’t think it has anything to do with any particular ecomorphs having more use for this ability than others as only one of the six ecomorphs is not represented, and it is also obvious that this trait is completely absent from some of the distinct lineages within Anolis (the genera proposed by Nicholson et al. 2012) while it shows up here and there in others. There are some species I suspect may possess the ability… such as A. conspersus, a close relative of A. grahami, but I have been able to find no mention or vocalization for this or any other species not listed above. I would love to hear if anyone has personally observed this for any other species (Anolis cybotes was the only cybotoid I had read about vocalizing, while all the others only came to my attention after an AA commenter gave an eyewitness testimony).

As to why this ability is present in some anoles in the first place, this seems to be a mystery. I know that a study was once conducted on A. grahami in which a few individuals were dissected and an attempt was made to identify sound producing structures, but none were found. The study also found that while the anoles vocalized while in aggressive confrontations, they did not respond to playback of these same vocalizations, at least not in the presence of visual stimuli, suggesting that these vocalizations do not play a pivotal role in anole social interactions. The effects of environment on whether an anole is able to vocalize are also probably negligent as the ability is present in all sorts of anoles, from mainland twig species living in mesic environments like A.salvini to West Indian xeric species such as A.whitemanni and all-around generalists like A.roquet of Martinique.

Then again, perhaps we are just looking too deeply into this. After all, when that anole squeaked at me I dropped him, which I’m sure is what he would have wanted to come out of that situation. Also, I have read that some anoles hiss ultrasonically when threatened or confronted; perhaps the big squeakers are just more intent on getting their point across.

Whatever the answer to this seemingly perplexing question is, I hope somebody figures it out eventually. Unfortunately I have stopped catching anoles and for the most part have stopped reading about them as well, so I probably won’t be adding any new species to the list. I hope anybody else with an interest in anoles comes across this post so they can find the full list of species. Unless there are more out there still, that is.