Anole Annals

Miami-Dade county, Florida; 18 March 2017

After scampering about much of North America the past few decades, I once again live in my hometown of Ormond Beach, Florida — on the northern edge of Volusia county. When I was a kid, back in the late 70s and early 80s, I spent much of my time tangling with and studying our local anoles. The Carolina greens (A. carolinensis) were dominant back then, covering our walls, windows, trees, and (sometimes by forced measure) our ear lobes. Every now and then I’d find a Cuban brown (A. sagrei) — usually around the shopping centers and strip malls. Nowadays, of course, that coin has flipped. The Carolina greens have moved back up into the higher foliage and the Cuban browns dominate our shrubs, walls, and windows.

I remember actually finding a Cuban brown anole on our property in 1984 or so. I was in 4th grade, drunk on Star Wars and lizards. I managed to catch the little non-native lizard and put it in my anole terrarium (a homemade wood-and-open-screen enclosure my dad and I built). I was in the habit of catching anoles (and the occasional snake), keeping and watching them for a day or two, and then releasing them back into the yard. Needless to say, the Carolina green already in the enclosure wasn’t too thrilled with his new roommate. Though guilt eventually kicked in the following day, I admit I was somewhat delighted by the defensive/discomfort color play of that poor Carolina green. Usually, they’d be cool, smooth emerald green with very little patterning… but distressed or riled up Carolina greens certainly know how to put on a good color and pattern show.

Soon enough, I released the Carolina green back into the yard and kept the Cuban brown for another day or two. This little moment of tension, however, leads me to the point of this post: the distress patterns of our local Carolina green anoles. More specifically, I’m interested in the presence of a supraspacular dark spot that shows up with some individuals. It’s a dark spot with light trim that sometimes appears just above and behind the front shoulder line — as seen in this particularly ornate individual photographed in Miami-Dade county on 18 March 2017:

Miami-Dade county, Florida; 18 March 2017

This Miami-Dade individual really stuck out to me. It’s patterning was distinct. It was quite large. It had that supraspacular spot. Most notably, it was still wielding quite a bit of green. Could this be A. porcatus? Like many naturalist-lizard enthusiasts, I tend to catch myself up in the eternal cycle of porcatus-or-not? when I’m in south Florida. Heh. Nowadays, my assumptions generally fall on the side of A. carolinensis unless I’m with somebody more in-the-know who can tell me differently with confidence; this hasn’t happened yet. Honestly, I have a hard time seeing a clear difference between the two. I’m glad I’m not alone.

Though distinct, this fabulously mottled Green wasn’t the only Green I’ve photographed with that supraspacular spot. Here’s an impressive male tangling with a Cuban brown anole in the Lower Keys of Monroe county, Florida, on 08 June 2007:

Monroe county, Florida; 08 June 2007

Further north, in my home territory, I’ve only noticed and photographed two individuals with that spot, albeit with less figure-ground contrast between the spot and the trim.

Orange county, Florida (05 September 2011):

Anolis carolinensis, 05 September 2011

Alachua county, Florida (05 December 2011):

Anolis carolinensis, 05 December 2011

Both were in WTF-dark-mode (as I call it).

Of note, I spent a few years in Valdosta, Georgia, intensely watching anoles.

Condition Dependence of Shared Traits Differs between Sympatric Anolis Lizards

By John David Curlis

On August 20, 2017

In New Research

A male slender anole (Anolis limifrons)

A walk through a tropical rainforest can reveal astonishing forms and colors of organisms – from vibrant poison frogs and coral snakes to the vegetative camouflage of stick insects and other cryptic creatures. Perhaps some of the most dramatic displays of variation can occur between the sexes, where males and females can differ so greatly in appearance that they resemble different species. Research in many systems has demonstrated that much of this variation is driven by sexual selection, the force responsible for the evolution of traits that are important for acquiring mates. Individuals may invest as much energy as possible into such sexually selected traits because doing so will give them a competitive advantage for mate acquisition. These traits are therefore considered condition dependent, as their expression is dependent upon the energetic condition of the individual that possesses them. While condition dependence has been the subject of many studies, it is not well known how it may vary between closely related species that share the same traits. If closely related species vary in condition dependence of their shared traits, then this implies that condition dependence could be important for the evolutionary diversity of sexually selected traits.

The rainforest at the La Selva Biological Station in Costa Rica

The lowland rainforest at the La Selva Biological Station in Costa Rica

Together with students from Grinnell College and Reed College, and as part of an OTS (Organization for Tropical Studies) course that I took as an undergraduate at the University of Virginia, we took to the lowland jungles of Costa Rica to answer this question. We studied two anole species from Costa Rica, the slender anole (Anolis limifrons) and the ground anole (Anolis humilis). Specifically, we tested whether several traits that they had in common exhibited condition dependence, including dewlap size, aspects of jaw morphology, and sprinting speed. To test for condition dependence, we first calculated two conventional indices of body condition, the residual index and the scaled mass index, which both take into account an organism’s mass, given its length. We then obtained residuals from the relationship between our variables of interest (dewlap size, jaw width, jaw length, and sprint speed) and snout-vent length (a measure of body length), which allowed us to control for the fact that trait sizes often scale with the overall size of an animal. Finally, we used bivariate linear regressions to test the effect of our indices of body condition on our residual traits of interest, with a significant positive relationship suggesting condition dependence. We found that dewlap size (a trait important for sexual signaling) and jaw width (a trait important for bite force and male combat) exhibited condition dependence in ground anoles, but not in slender anoles. In contrast, neither sprint speed nor jaw length were condition-dependent in either species. Importantly, the presence of condition dependence in one species, but not the other, implies that the condition dependence of shared traits is evolutionarily labile. Additionally, by detecting condition dependence in the dewlap of ground anoles, which have a larger dewlap given their body length when compared to slender anoles, our findings may indicate that the strength of sexual selection differs between these two species. Lastly, our research suggests that variation in condition dependence of the dewlap among species could contribute to the extraordinary diversity of dewlaps in the Anolis genus.

If you would like to read the full paper, published in the Journal of Experimental Zoology Part A, go to:http://onlinelibrary.wiley.com/doi/10.1002/jez.2076/epdf

Anole Ecomorph Watches 50%–Today Only!

By Jonathan Losos

On August 18, 2017

In All Posts

Note: the watch on the bottom right is not one of ours!

It’s that time again. For one day only, Zazzle.com is offering 50% off the Ecomorph line of watches. Sale Code:

COOLZAZSTYLE

And we’re open to suggestions for new species to feature on a lovely wrist fob. Suggest away!

Signals and Speciation: Do Dewlap Color Differences Predict Genetic Differences?

By Julienne Ng

On August 12, 2017

In New Research

Dewlap and genetic differences between co-occurring Anolis distichus and A. brevirostris

Dewlap and genetic differences between Anolis distichus and A. brevirostris at sites where they co-occur on Hispaniola.

Here at Anole Annals, we’re all familiar with the replicated evolution of different anole ecomorph types in the Greater Antilles. However, divergence into these different ecomorph classes is not enough to explain how the group became so speciose on these islands. Additional factors must therefore have promoted speciation throughout the history of the group.

One potential factor is the flashy anole dewlap. Dewlap diversification across anoles has led to the remarkable array of dewlap color, pattern and size we see today. If dewlap differences did indeed drive speciation in anoles, or are involved with the maintenance of species boundaries, we might expect that as differences in dewlap color and pattern increases between species, genetic differentiation will also increase through fewer hybridization events.

In our study that just came out in the Journal of Herpetology, Rich Glor, Anthony Geneva, Sabina Noll and I set out to test this using two widespread species from the Anolis distichus species complex, A. distichus and A. brevirostris. These two species co-occur in many locations on Hispaniola and, while they often differ in dewlap color where they do co-occur (yellow with an orange patch vs. all pale yellow), in other areas, they co-occur with similarly pale dewlaps. Using mitochondrial DNA, microsatellite and AFLP data, we investigated patterns of genetic differentiation at four sites: two where the species differ in dewlap color, one where the species share the same dewlap color, and another where pale dewlapped A. brevirostris co-occurs with two A. distichus subspecies (one with a similarly pale dewlap and the other with an orange dewlap).

In general, we found that A. distichus and A. brevirostris looked like “good species,” with strong genetic differentiation and little evidence of hybridization, even at a site where they share the same dewlap color. This suggests that dewlap color differences are not associated with genetic differentiation in a manner one might expect if dewlaps were involved in the speciation process or in maintaining species boundaries. However, at the site where A. brevirostris co-occurs with two A. distichus subspecies with both similar and dissimilar dewlap colors, we found some evidence of hybridization and the species were not as highly genetically differentiated. This discrepancy suggests that site-specific factors could be influencing the dewlap’s role in speciation or maintaining species boundaries. For example, as Leo Fleishman’s and Manuel Leal’s work has shown (e.g. 1, 2, 3), the dewlap’s effectiveness as a signal is dependent on the light environment. Further understanding about the environmental differences among our study sites, how species utilize the available light microhabitats within each site, and how the dewlap looks to anoles at each site could provide more insight into our findings.

On the other hand, perhaps we need to be looking beyond the dewlap and focusing instead on whole signaling displays. Anole behavioral displays can also be strikingly different among species (e.g. 1) and may instead be the key to understanding species diversification in Greater Antillean anoles.

Arthropod Predators of Anoles

By Christian Perez

On August 10, 2017

In All Posts

Orange-legged wandering spider (Cupiennius coccineus) consuming house gecko (Hemidactylus frenatus) at Sirena Biological Station, Corcovado, Costa Rica

Red-legged wandering spider (Cupiennius coccineus) consuming a house gecko (Hemidactylus frenatus) at Sirena Biological Station, Corcovado, Costa Rica

When someone first asked me about the major predators of anoles, my first thought was to talk about curly-tailed lizards (Leiocephalus carinatus) in the Caribbean, vine snakes (Oxybelis spp.) in the neotropics [see my previous post on anole predation by O. aeneus at La Selva], and birds. I think that as herpetologists, we tend to fall into the trap of thinking of invertebrates as “lesser” taxa to be preyed upon by small vertebrates like lizards, and in turn for small vertebrates to be eaten by larger vertebrates.

I, too, when thinking about how selective pressures shape morphological variation in mainland and island habitats turned to fellow herps and birds as the primary predation pressure for mainland anoles. However, it wasn’t until I arrived in Costa Rica that I discovered the high prevalence of voracious arthropods, and I realized that our beloved lizards had much more to fear!

Orange wandering spider (Cupiennius getazi) with egg sac at La Selva Biological Station, Costa Rica

Red-legged wandering spider (Cupiennius coccineus) eating a pink katydid (Tettigoniidae: Phaneropterinae) at La Selva Biological Station, Costa Rica

A large adult female mantis (Phasmomantis championi) at La Selva Biological Station, Costa Rica

Conehead katydid (Tettigoniidae: Conocephalinae: Vestria sp.) at La Tarde, Osa Peninsula, Costa Rica

In a single night at La Selva, I could easily find dozens of large wandering spiders (Ctenidae), and if I pointed my headlamp higher in the trees I could see eyeshine from hundreds of spiders. Given the high density of large ctenids at La Selva, it is not unlikely that anoles and small tree frogs constitute a major portion of their diet. In fact, I wouldn’t be surprised if large arthropods are one of the most common predators of mainland anoles in some regions.

The same might be the case for giant mantids of the genera Macromantis and Phasmomantis, and conocephaline katydids sporting fearsome mandibles (e.g. Copiphora spp.). Since the invasive Chinese mantids (Tenodera sinensis) in North America are well documented to prey on hummingbirds almost equal in size to the mantids [see Nyffeler et al. 2017], surely larger and bulkier species in the neotropics can take lizards much smaller than themselves. Even though wandering spiders and conehead katydids are primarily nocturnal hunters, I have heard many stories of these arthropods being implicated in anole and tree frog predation. Research looking into how ctenids and nocturnal katydids forage would help determine if they can actually detect sleeping anoles or if predation events occur from the arthropods simply running in to the anoles while on the move.

If anyone here on Anole Annals has any anecdotal or photographic records, please comment below.

To throw a twist on this discussion, is it possible for a spider to prey on a lizard two and a half times its size? A new paper about a vertebrate-eating jumping spider (Salticidae) describes just that! Considering arthropods as possible major players in anole predation could shed light on behavioral and ecological studies of mainland anoles.

Figure 1 from Nyfeller et al. 2017, showing female jumping spiders (Phidippus regius) consuming Carolina anoles (Anolis carolinensis) and Cuban tree frogs (Osteopilus septentrionalis)

Here are a few more spider photos to wrap up this blog post.

Jumping spider (Salticidae: Phiale cf. guttata) eating an assassin bug (Reduviidae)

Red-legged wandering spider (Cupiennius coccineus) consuming house gecko (Hemidactylus frenatus) at Sirena Biological Station, Corcovado, Costa Rica

Another angle of a red-legged wandering spider (Cupiennius coccineus) consuming a house gecko (Hemidactylus frenatus) at Sirena Biological Station, Corcovado, Costa Rica

Threat display of a Brazilian wandering spider (Phoneutria boliviensis) from Tárcoles, Costa Rica. A ctenid with medically significant venom.

A New Method for Taking Toepad Pictures in the Field

By Colin Donihue

On August 8, 2017

In Research Methods

Getting good pictures of lizard toepads in the field can be tricky. Flatbed scanners are heavy and don’t take well to transit bumps and bruises, and getting a digital camera to focus on the toe, not the glass, requires surgical precision on the manual focus ring. I’ve just found a new solution for an iPhone (or GooglePixel, if that’s how you roll), and I’m eager to share.

Here’s what you need:

An iPhone 6 or 7 series or a GooglePixel, the Moment Lens mounting case ($29.99) with the Moment Macro Lens ($89.99), a clear surface, a scale bar, your headlamp, and a laptop.

Here’s the setup in action (and, by the way, this particular lizard’s bite force was classified as medium-ouch):

You’ll notice that when the camera is facing up the iPhone screen is facing down. Obviously this makes it difficult to snap the photo—enter the app WiFiCam. This app enables you to type the phone’s IP address into your web browser and remotely trigger the camera, as long as both devices are on the same wifi. It’s very simple, and the price was right (free!).

And so here’s the whole shebang:

(Don’t forget to keep a tissue handy for wiping up lizard poop!)

And not to bury the lede, but the results are fantastic (see above).

A few things to note:

The white plastic platform around the lens ensures perfect focal distance so getting your lizard as close to that plane as possible is ideal. I tried a square of single pane glass but wasn’t tremendously pleased with the results. The above is taken with a cheap plastic petri dish, which works great but scratches quickly. Another option I’m going to look into is a glass microscope slide. (The biggest drawback to the slide is that it’s smaller than the camera lens platform… meaning that the lizard can actually poop ON YOUR PHONE. And believe me, they will.)
The app works fine for controlling the shutter, but it’d be nice to be able to also control other camera settings like focus point and brightness or contrast. There might be other apps out there that do all of that; I just haven’t tried to find them yet. If you’re taking photos of lizard toepads in a place without wifi (as you most likely are), you can use your computer to create a local network and pair the camera to the computer that way.
I found that the sidelight was really helpful to get good illumination on the toes. Without the sidelight the camera sometimes adjusts for ambient light behind the foot, making the lamellae hard to see. My headlamp was the perfect size and brightness and worked great.

One last thought: Moment also has a fisheye lens that might do a really nice job of canopy cover photos in the field. That’s on my short list of things to experiment with in the near future!

I’d love to hear your thoughts on how to improve the system in the comments.

Help Identify Costa Rican Anoles

By David Weisenbeck

On August 6, 2017

In All Posts

I recently saw these four anoles on a trip to Costa Rica. All four were sighted in La Fortuna in the province of Alajuela. They were sighted on July 18th and 19th, all within a few meters of a forested stream. I have some ideas about their ID’s, but am not completely sure. Can anyone help me with their identification?

This first anole was found on a tree trunk near the stream at night, while the second one was found on a pole in the morning. Both Anolis lionotus?

This third one was found on a low shrub in the morning. Anolis limifrons?

The fourth anole was found on a low-growing shrub at night. Anolis lemurinus?

Thank you in advance for your help.

Shades of Bumpus: Polar Vortex-Induced Natural Selection on Cold Tolerance in the Green Anole

By Jonathan Losos

On August 3, 2017

In All Posts

Graphic by Julie McMahon.

Shane Campbell-Staton had fortuitously measured the thermal physiology of a number of populations of the green anole, Anolis carolinensis, the summer before 2014’s Polar Vortex. So, he went back and examined the survivors. And sure enough, in the most southerly populations, those most strongly affected by the cold snap, natural selection had occurred. Shane tells Scientific American all about it in this podcast. The nifty figure above comes from the University of Illinois’ press release.

More Information on the Knight Anole Invasion of the Turks and Caicos

By Jonathan Losos

On August 2, 2017

In All Posts

We reported recently that knight anoles (Anolis equestris) have shown up in the T&C. Here’s more on the story from B Naqqi Manco, the Terrestrial Ecologist at the Department of Environment and Maritime Affairs, Turks and Caicos Islands Government:

Cuban knight anoles are currently known from two sites on Providenciales: Vicinity of Beaches Resort in The Bight and Amanyara Resort on Northwest Point. Both populations showed up after the importation of large trees for landscaping from Miami. The properties are both irrigated pretty heavily to keep the bigger trees going. The tree imports were brought in before the Department of Agriculture was fully operative, so unfortunately things got in at that time that probably shouldn’t have made it through.

I don’t have confirmation of the knight anoles breeding, but I know The Bight population has been spreading with individuals having been found on adjacent properties and in a nearby residential neighbourhood. I would be very surprised if they’re not breeding on either site. Unfortunately we don’t have the capacity to monitor them well but this is something we want to keep a closer eye on and it would make a worthwhile research project for a student or intern.

Thus far, they have not been reported from any other island or cay.

New Paper Says Anoles Are the Reason for Dave Wake’s Career-Long Focus on Salamanders

By Jonathan Losos

On July 30, 2017

In All Posts

Dave Wake: the younger years

The paper, by Nancy Staub and Rachel Mueller and just out in Copeia, is a delightful biography of DBW, as he is referred to by his lab and many others. As for the anole bit, you’ll have to read it to find out.