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We’re back in the Bahamas for our yearly trip monitoring evolution of brown anoles on small islands (most recently reported on a year ago).  These populations were hammered by Hurricanes Irene and Sandy in 2011 and 2012, and are just now recovering. Most exciting to us was one population reduced to two individuals, which seemed to disappear during the course of our visit last year. Had the population gone extinct? No–we’ve found 14 lizards there this far. Hooray.

Part of what we do is capture lizards, bring them back to the field lab, and x-ray them to measure their morphology, to see how morphology changes from one year to the next. And while doing so, we see all kinds of interesting anomalies. For example, check out the left hind leg of this female–she’s missing most of the toes on that foot. Turns out that that lizards lacking the full complement of digits is not very unusual (check out this post from several years ago on more severe mutilations).

But this year we’ve had some more unusual sightings. Check out the left knee of the male below. Clearly, he broke his femur and it grew back oddly. Yet, it works–this guy was fat and sassy. It would seem amazing that a lizard could break its femur and survive, but here’s the proof.

And check out the tail on this guy. Looks wacky, right?

The x-ray, however, doesn’t do it justice. It’s not only wickedly bent to the side, but also upwards!

Photo by Manuel Leal

Who knows what we’ll find tomorrow?

Club LizKids appears to be the new healthcare.gov…

Many of you visited my lab’s website for kids – lizardsandfriends.org – in the past few days, and a good number of you signed up your children to be a member of our Club LizKids email list.  Thanks so much for your interest!  We hope you and your kids will find this to be a fun group.

BUT, in my recent communication with some of you, I’ve learned that only some of the Club LizKids notifications were coming through to me, even though you received a message confirming your submission.  My web developer (the amazing Tara Whittle) jumped right on that, and we’ve now fixed the problem.  So, if you tried to register for LizKids earlier, please do so again!  

Anolis limon on top, and the closely related A. chocorum (middle) and A. ibanezi (bottom).

The parade of new anoles continues, and this one is beautiful! Velasco and Hurtado- Gómez, in a new paper in Zootaxa, describe a new species of green anole from northwestern Colombia, Anolis limon. The species is closely related to other green lovelies, but differs in dewlap color and a few other characteristics.

As we have chronicled in these pages, the number of anole species continues to rise, up to 388 according to these authors. More importantly, Colombia—lucky place—is the global leader in anoles, with 75 species.

Here’s the etymology of the name: “The specific name limon makes reference to the resemblance of the body color of the females to the green color of the fruits of the lemon tree (Citrus x lemon).”

And the figure below reveals the distribution of the new species and others.

I’ve been re-watching some of my Sitana videos from 2012, and was reminded of an odd interaction between an Indian robin and a male fan-throated lizard (Sitana ponticeriana), from a population in Kutch, Gujarat, in western India. Usually, Indian robins and fan-throated lizards don’t pay much attention to each other. Here’s a video in which a lizard displays when a pair of robins pass by. His dewlap remains extended for a while, which is uncharacteristic, but the interaction doesn’t escalate:

But in the same population, an Indian robin chases after a male fan-throated lizard, after the lizard first ran in the direction of the robin. He starts perched on the rock in the centre of the screen. Here’s a video, slowed down to half-speed. When filming,  I had no idea what was happening, or even where the lizard was, which explains why the camera deviates from the lizard for a while (apologies). 

I’m not sure what’s going on. I didn’t think robins eat lizards–do they? Maybe it thinks the lizard’s tail is a worm? Maybe it’s just playing? Any further ideas?

I don’t think I’ll run into any disagreements by claiming that Anolis vermiculatus is hands-down one of the coolest anoles in existence. First of all, it’s huge – up to 123mm SVL for males. They have blue eyes. They are capable of eating fish and amphibians. They can run across water, and are “truly aquatic” (Schwartz & Henderson 1991). The males in particular seem more like crested water dragons than anoles. A. vermiculatus is sometimes called “lagarto caiman” in Cuba. Although this might bring to mind Dracaena for some, Anolis vermiculatus is quite a different animal. Nevertheless, the name seems appropriate after meeting the creature.

We got our first chance to see A. vermiculatus while staying in Viñales, a lovely, foggy town surrounded by towering limestone mogotes home to Anolis bartschi. We had originally expected to see them only in Soroa, a legendary locality for Anolis in Cuba and a short drive from Viñales. However, we discovered them in abundance along the densely vegetated banks of the mud-brown stream running between our hotel and the road.

A blue eyed Anolis vermiculatus

I generally found A. vermiculatus to be the hardest lizard to get a decent picture of that we encountered (with nods to A. equestris and A. vanidicus). Their preferred habitat is full of shade, and A. vermiculatus is quick to retreat there, often spotting clumsy humans from long distance. If molested further, they leap into the water and apparently remain submerged for some time.

The next day, we were scheduled to have an hour in Soroa, but a bus breakdown allowed us two entire hours. We found more A. vermiculatus, a bit more light, and much clearer water, but the lizards remained a wary bunch. Below are females and a juvenile rafting in what looks like a coconut husk. Sexual dimorphism in this species is significant for size (123mm max SVL for males, 83mm for females, Schwartz & Henderson 1991), and coloration.

I did get the chance to photograph two large males. This individual appears to have some sort of parasite (notice the swelling on the side of the neck). Anyone have any ideas what it could be? My guess would be a nematode. I’m unsure if the deformity of the jaw is another of these parasites or perhaps a different injury.

Although A. vermiculatus is able to run across the surface of water, we did not observe this behavior in our short time with the species. However, it was quite surprising to learn that these lizards do this without the assistance of toe fringes as in Basiliscus.

Here’s the best shot of the bunch:

Next up: a blue lizard that wears yellow pants!

httpv://www.youtube.com/watch?v=zDtDtn5n8-A

A new movie on snake research, an Alex Pyron production, features not only great snake footage, but cameo appearances by anoles and Frank Burbrink explaining how he got out of prison and into herpetology (see disclaimer below), as well as wildfires in the Brazilian Cerrado, and plenty of other frogs, lizards, and rock and roll music.

Alex explains: “Most people think of science as being fairly boring most of the time. They are probably right. However, readers of this page are more likely familiar with another side of the story. Those of us who do field work are lucky enough to get paid to flip rocks for a living, chasing after the most exciting creatures on the planet. Books like Snakes and Snake Hunting and The Snake Charmer captured some of this adventure, and gave many of us an early glimpse into the future careers that awaited us. Bringing this magic to the silver screen is snakehandlers: these signs shall follow them, the new documentary about field herpetology that you never knew you needed (or wanted).

Shot across one year, snakehandlers follows Alex Pyron and a rotating band of pirate misfits across the U.S., Panama, Ecuador, and Brazil in search of tissue samples from the rarest (and commonest) herps around, to fuel the fires of our phylogenetic frenzy. Along the way, a wildfire rips across the Brazilian Cerrado, the clouds boil in the Northern Andes, Frank Burbrink shares his hard-luck tale of crime and punishment on the road to redemption from state prison to evolutionary biology*, famous herpetologists from the past speak to us across time, and new species are discovered left and right.

At its core, snakehandlers tries to answer the question of why we work with snakes to begin with. Herpetologists from every corner share their stories about the interests and experiences that brought them into the field. On the whole, though, the question remains unanswered; how could it be? Why do we do something as crazy and absurd as handle snakes or chase anoles? Watch snakehandlers and see if you can figure that out for yourself, in a movie that does for snakes what Plan 9 did for Outer Space.

As a plus (or a main attraction) for readers of Anole Annals, have fun spotting at least six species of Anolis from North, Central, and South America! Happy herping…

*The producers of snakehandlers were unable to verify the accuracy of all participant interviews.”

Which species owns this lovely tail crest?

Some anoles sport fancy dorsal tail crests. It would be interesting to survey the distribution of tail crests–they are only found in some areas, and species of some sizes and not others, and those in particular microhabitats. Quick–can you think of a mainland anole with a tail crest?

But I’m guessing the species above is not one that comes to mind when you think of tail-crest bearing species. Whose is it? The answer’s below the fold.

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A recent study in Oecologica by Terry Ord and myself found striking parallels in habitat use and morphology between the phylogenetically distinct Anolis and Draco genera.  Draco (family: Agamidae), for those who don’t know, is a genus of gliding lizards found throughout southeast Asia that are similar to anoles in that they communicate with conspecifics using bright and diversely coloured dewlaps (see picture).

(L: Draco sumatranus; R: anole)

A defining characteristics of anole ecology is their ecomorphology – a description of the species microhabitat and its morphological adaptions for thriving there. Anole species living sympatrically avoid interspecific competition by partitioning their habitats and resources, and consequently develop morphological adaptations that are suited to their slice of the habitat. As Draco species are also often found in sympatry, we tested whether competition pressures had resulted in similar habitat partitioning and corresponding morphological characters (or ecomorphs). Whilst it’s perhaps a bit early to suggest that Draco have  evolved the full complement of anole ecomorph classes, the Draco taxa studied largely clustered into two groups that shared characteristics with the Greater Antillean anoles. The figure below (panel b) shows a combined Draco/anole phenogram, based on morphology and ecobehaviour (the anoles are labelled only by ecomorph). The Draco species fall out largely in line with groups of ‘trunk-ground’ anoles towards the top of the phenogram, and ‘trunk-crown’ anole towards the bottom.  

One of the better diagnostic features of the Greater Antillean anole ecomorphs are the differences in perch use and subsequent differences in limb length. The plot below shows total hindlimb length (size-free residuals) of adult males of Draco species and Greater Antillean anoles, as a function of perch circumference.  The relationship between limb length and perch size is nearly identical between the groups, with a very similar slope, and only a difference in y-intercept owing to differences in body length (Draco bodies are elongated to accommodate gliding membranes).  The same unit increase in perch size results in the same unit increase in limb length for both genera.

These results are surprising considering that this relationship has not been found in species that are more closely related to the Greater Antillean Anolis (see study for references) and because Draco and Anolis have very different ‘key innovations’ for locomotion in their respective habitats (toe pads for Anolis and gliding membranes for Draco). This implies that Draco species have experienced interspecific competition over resources in similar ways to the anoles, resulting in homologous character displacement. 

It’s an old story: a Cuban émigré arrives in Florida, thrives and then sends out roots, in the process becoming completely Americanized. I refer, of course, to the green anole, Anolis carolinensis, derived from grand-daddy porcatus in Cuba. But the exact story of carolinensis‘s spread–when, by what routes, where–is still unclear. Two years ago, a pair of papers reported interpretations based on sequences of mitochondrial DNA, revealing a somewhat complicated history of green anole diaspora. Now, in a recent paper in Genetica, Tollis and Boissinot revisit this question, bringing to bear the power of a multi-locus, nuclear gene sequencing effort. Their results lead to a simpler, more satisfying story, and suggest that we need to be wary of placing too much faith in phylogeographic/evolutionary scenarios derived from mitochondrial DNA.

Here’s the tail end of their abstract:

“We find that all demographic events occurred during or after the Upper Pliocene and suggest that green anole diversification was driven by population divergence on interglacial island refugia in Florida during the Lower Pleistocene, while the region was often separated from continental North America. When Florida reconnected to the mainland, two separate dispersal events led to the expansion of green anole populations across the Atlantic Seaboard and Gulf Coastal Plain.”

Their inferred evolutionary relationships are portrayed above, and their biogeographic scenario below.

Hard at work studying lizards (from a previous AA post on best practices in lizard videotaping in the field)

The New York Times reported today on a recent paper in Nature Methods that indicated that stress levels of lab rats varied depending on whether the scientist in the room with them was a man or a woman. This effect existed even in response to t-shirts worn by a man or a woman.

This got me thinking: could the same factor effect lizard behavior studies? In many cases, anoles are studied by an observer quietly watching or recording lizards from a distance of a few meters. Many anole species seem unperturbed by the presence of observers and go about their activities in a seemingly natural way. But does the presence of an observer have an effect? Are they warier? Do they display less? And, more to the point, does the identity of the observer have an effect? Men are, on average, bigger than women, so might that matter? Some people are more fidgetty than others. Clothes? Facial hair? I am aware of a few studies on observer effects on lizard behavior (such as this one on the brown anole), but not many.