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We were long overdue for a little make-over here at Anole Annals, so we just updated our WordPress theme. We’re also going to be adding some new header images derived from this year’s  photo contest. We will include a credit to the copyright holder on each image, but please let us know if you’d prefer not to see your image in our header. We hope you enjoy the new look and please let us know if you notice any problems.

Editor’s Note: The sale has been extended until midnite Saturday night!

If you’re going to buy a Anoles 2014 calendar, do it now. Zazzle.com is having a Black Friday sale, and calendars are 60% off until 2 pm Eastern time. Order your calendars here with code BLKFRIZAZZLE.

Book-ended by this year’s photo contest winners, the 2014 anole calendar features 13 spectacular anole photographs selected by you, Anole Annals’ readers. Unlike previous year’s calendars, this year’s edition has a heavy South American influence thanks to photographs by Lucas Bustamante and Diana Troya. In addition to the two contest winning snaps of A. chrysolepis and A. gemmosus, other pin-ups include A. princeps, A. proboscis, and A. biporcatus. That’s not to say that some of our favorite Caribbean species don’t also make an appearance. Hispaniola is particularly highlighted, thanks to several photos by Cristian Marte, including stunning shots of A. bahorucoensis and A. coelestinus. in addition, there’s a lovely silhouette of A. sagrei displaying and an intriguing vignette of a tree boa and a sleeping A. aeneus. Check them all out at zazzle.com, where the calendars are now on sale. Til midnite tonight, you can get 20% with the discount code “TDAYPOSTSALE.”

Editor’s Note, Monday, Dec. 2: 60% off until 1 pm Eastern time today, code : ZAZZLEMONDAY

Sorry to post this right before Thanksgiving dinner, but here is something to think about the next time you eat after handling an anole: approximately 30% of anoles in Japan carry salmonella, twice the level in feral goats and more than ten times greater than that found in public toilets. Read the complete (freely available) study here.

 

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