Egret Eats Green Anole

On October 6, 2017

Photo by John Karges

We’ve seen this before. Anoles are, alas, no match for these large and wily marauders. John Karges provides the story: “The egret was flying down the riparian woodland corridor over a side channel, and abruptly landed in the mid-story thicket overhanging the stream and immediately began a stalk. It lunge-grabbed the anole, and very quickly devoured the adult anole in a matter of seconds.”

And here’s where it went down: 2 Oct 2016 San Antonio Mission NHP, San Antonio, Bexar County, Texas.

And the inevitable outcome.

Photo by John Karges

Keep Your Enemies Closer: Green Anole Seeks Safety in the Coils of a Snake

By Oliver Ljustina

On October 4, 2017

In All Posts

The head of the Green Anole is circled in white. The tolerance of the Cornsnake was perhaps aided by what appeared to be full belly.

Snakes love anoles, though their affection is seldom reciprocated. Unsurprising. But, it seems a snake/anole relationship which leaves the anole happy and undigested is not beyond the realm of possibility. In a recent natural history note, published in Herpetological Review, James Stroud and I describe an unlikely friendship I happened upon while working as a field technician in Miami FL. While collecting samples and doing routine maintenance on an automatic water sampler in Everglades National Park, I found a Green Anole (Anolis carolinensis) nestled within the coils of a large Cornsnake (Pantherophis guttatus) inside the external battery housing of the sampling unit. At first, my delight was focused on the snake (such encounters were a big perk of the job), but then I noticed a slender head regarding me cautiously from the safety of the coils. After a moment, the lizard slowly pulled its head fully underneath its protector, and I closed the lid on the snake/lizard duo, content the battery was in working condition. It was a cool day, and I was happy that I did not need to disturb the animals.

Given the tendency of snakes to make meals out of anoles, this encounter struck me as odd. After casually mentioning it to James Stroud, he immediately suggested this as a possible incident of kleptothermy, which describes a thermoregulatory process by which an organism regulates its body temperature by stealing the warmth of other organisms. The snake was certainly much larger, and so even though it was a fellow ectotherm, snuggling up to it would have likely provided some increase in thermal inertia. Thermal benefits aside, did the oblivious(?) guardian also provide protection against smaller Cornsnakes, perhaps more used to preying on anoles of that size? Did the lizard even realize what it had decided to make its bed upon when it crawled into the dark confines of the battery housing? We may never know.

Anolis scriptus on Turks and Caicos, and the Threat of Rats

By Jonathan Losos

On October 2, 2017

In All Posts

Concerns Raised over Introduction of Festive Anole to Bermuda

By Jonathan Losos

On September 30, 2017

In All Posts

From the September 28, 2017 edition of The Royal Gazette, the daily newspaper of Bermuda.

Fears over lizard arrival

Jonathan Bell

Sep 28, 2017 at 8:00 am

Bermuda’s latest lizard arrival, the brown anole, appears to be thriving but is prompting concern over the island’s endangered natives.

The lizards, first seen in 2014 and recently spotted on the grounds of Aberfeldy Nursery in Paget, are suspected to have arrived from Florida.

One of that state’s most abundant lizards, the anole arrived there from the Caribbean, where it is native to the Bahamas and Cuba.

Popular as pets but aggressive breeders in the wild, the lizard, distinguished by ridges on its back, has proliferated in the southern United States.

According to the Department of Environment and Natural Resources, Bermuda has two distinct populations of brown anoles.

Genetic analysis shows that the two groups came from “separate founding events”, meaning the second did not arise from the first.

Noting the lizard’s capacity to spread rapidly, Jonathan Starling, executive director of the environmental group Greenrock, voiced concern that the anole would ultimately crowd out Bermuda’s imperilled skinks.

“Unlike the three other Anolis species known to be in Bermuda, the common blue Jamaican, the Warwick or Antiguan and the Barbados, this one is primarily a terrestrial species, the rest being arboreal or tree dwelling,” Mr Starling said.

“The endemic Bermuda skink, already at critically low populations, is also a primarily terrestrial species, so this new lizard poses a much bigger threat to it than the others did.

“I am not aware of the current range of this new lizard but I believe it is still confined within Pembroke and Paget parishes, so at the moment it is not coming into conflict with the remaining known skink populations. However it is likely their range will expand and come into contact with known skink populations within a decade, if not sooner.”

The unwelcome development is the latest of many threats to the endemic skink, which are easily trapped and killed by discarded bottles and cans.

Skinks are also at jeopardy from storms, as well as predation from other invasive species such as cats and rats.

“We’d hope that new initiatives, such as mandatory recycling or a bottle bill, would at least reduce that particular threat to skinks, which would likely benefit them in handling the novel threat posed by this invasive lizard,” Mr Starling said.

Keeping Up With The Anole Literature

By Anthony J Geneva

On September 28, 2017

In Research Methods

For anole biologists and enthusiasts, there are several ways to keep up with the latest and greatest anole research. These include RSS feeds, social media outlets such as Twitter, and email alerts from websites like Google Scholar (or from Anole Annals! – see the box on the right-hand side of this page). Nonetheless, the amount of literature that already exists on our beloved anoles can sometimes seem overwhelming. Modern search engines have made identifying this work easier than ever before, and we believe that continuing to promote the visibility and accessibility of anole literature will only strengthen our research community. With that in mind, we have created a resource that we hope will be helpful to those of us who spend our time steeped in anole literature.

The resource is a bibliography of Anolis literature, through the end of 2016, which we have compiled via searches of manuscript databases and manual curation. Here are some things you should know:

We intend to update the bibliography at the end of each calendar year. Thus papers published in 2017 will appear early in 2018.
The bibliography certainly contains errors and omissions. You can help us improve it! The file used to generate the collection can be downloaded, edited, or updated on GitHub. Any suggested edits will be sent to us for approval, and we’re excited for those start coming in.
The bibliography is a BibTeX file, a format used by the Latex markup language. Free software like Bibdesk, JabRef, and BibTool can be used to open BibTex files directly.

Lastly, and most importantly:

Most major citation software packages (e.g. Endnote, Papers, Mendeley, Zotero) can import BibTeX files. By importing the BibTeX filed used to generate this bibliography into your own citation manager, you can have the full value of this collection at your fingertips. Major benefits of doing so include the ability to easily search and filter within the bibliography, and of course, to instantaneously generate a list of citations from any subset of the full list.

We hope that AA readers will find this resource useful. We also look forward to hearing your suggestions for its improvement! Lastly, we’d like to thank members of the Losos Lab for assisting with the construction and curation of the collection.

This post was co-written by Anthony Geneva and Nick Herrmann.

Evidence for evolutionary determinism in the signal design of lizards?

By Simon Baeckens

On September 24, 2017

In New Research

Photographs of a subset of lacertid lizard species used in this study. From the left top to the right bottom: Acanthodactylus beershebensis, Lacerta bilineata, Dalmatolacerta oxycephala, Podarcis melisellensis, Tropidosaura gularis, Podarcis siculus, Heliobolus lugubris, Algyroides nigropunctatus, Lacerta media.

The vast array of signals used in animal communication is a continuous source of awe and a hot topic in evolutionary and behavioral research. One important factor contributing to the signal diversity we witness today is ‘signal efficacy’: the ability of a signal to travel efficiently through the environment and attract the receiver’s attention. With this in mind, natural selection is expected to mold signal design for maximum efficacy of information transmission and detectability, leading to signal variation among populations/species living in different environments. To illustrate, a recent study by Tess Driessens and colleagues assessed the degree of variation in the dewlap design of Anolis sagrei by comparing 17 populations distributed across the Caribbean (Fig. 1).

Phylogenetic relationships among seventeen Anolis sagrei populations. Pie charts illustrate dewlap pattern proportions for each population per sex (black = solid; light grey = marginal; dark grey = spotted). Photographs represent male and female dewlaps of typical individuals from every population.

Fig. 1 — Phylogenetic relationships among 17 Anolis sagrei populations. Pie charts illustrate dewlap pattern proportions for each population per sex (black = solid; light grey = marginal; dark grey = spotted). Photographs represent male and female dewlaps of typical individuals from every population.

Their findings showed large interpopulational variation in dewlap size, pattern, and color, and more interesting, they established a link between the dewlap design of brown anoles and the environment they live in. Lizards occurring in more ‘xeric’ environments had a higher proportion of solid dewlaps with a higher UV reflectance; lizards inhabiting ‘mesic’ environments had predominantly marginal dewlaps showing high reflectance in red. This was true for both males and females. Like Ng et al. (2011) and their observations on dewlap variation in A. distichus across an environmental gradient, Driessens et al. (2017) interpret their findings as evidence for adaptive divergence of a signaling apparatus.

Surprisingly though, while there are numerous great examples of comparative studies finding support for convergent evolution in visual and acoustic signaling systems, (e.g. Endler 1992; Fleishman 1992; Nicholls & Goldizen 2006, to say a few), similar (comparative) studies, but then, on the phenotype of chemical signals are almost entirely lacking. This is probably due to the combination of only very recent developments in chemical analytical and statistical comparative tools, the time researchers need to assemble a large-scale multi-species chemical dataset, and perhaps due to our own predisposition to visual and auditory signals. Currently, the proper analytical tools for studying natural products chemistry are available and affordable, permitting comprehensive taxon-wide research on the evolution of chemical signal diversity and design. Ultimately, there has never been a better time as now to be a comparative chemical ecologist.

Photograph of the cloacal region of a male lacertid lizard (Lacerta agilis), showing his numerous femoral pores with protruding glandular secretion.

Finally, three Belgians, two Spaniards and one Greek (sounds like the start of a joke with ample potential) took up the challenge to examine variation in the chemical signal design of lizards. Although underrepresented in studies on chemical signal diversity, lizards are an excellent group for investigating chemical signal evolution, as many of them they bear numerous glands on their thighs that secrete waxy substances, which they deposit while moving through their habitat. These secretions are often considered the leading source of chemical signals involved in lizard communication.

The study started with a quest. A quest to collect gland secretions of as many species as possible (within a PhD timeframe). Luckily, we were fortunate enough to be able to count on the help of many collaborators (Shai Meiri, Chris Broeckhoven, …). We focussed on lacertid lizards, as they are a species-rich family distributed over a wide geographical area, and known to rely strongly on chemical communication in several contexts.

In total, we sampled secretions from 64 species throughout, Europe, Africa, and Asia, covering a wide array of habitats and climate regions: from the Mediterranean maquis over the alpine meadows in the Pyrenees Mountains, to the sandy Israeli dunes and the Kalahari Desert of South Africa (Fig. 2). Back in the lab, we determined the chemical composition and chemical ‘richness’ (number of different chemical compounds) of the secretions using GC-MS, and obtained climate data for all catch-localities from online databases.

Fig. 2 — Map showing the sample localities of the 64 lizard species under study.

Our gathered data showed considerable variation in the chemical richness and composition of lacertid secretion. Shared-ancestry failed to explain among-species patterns of variation, hinting that chemical signals may change relative rapidly. Most interestingly, our findings revealed a strong relationship between the environmental conditions species live in and the chemical composition of their glandular secretions. On the one hand, lizards living in ‘xeric’ environments, characterized by high temperatures and arid conditions, contained higher proportions of stable and heavy-weight compounds in their secretions. Hot and dry conditions increase the evaporation rate of chemicals, and so, decreasing the longevity of a signal. Stable and heavy-weight compounds most likely reduce evaporation rate and counteract the rapid signal fade-out through evaporation, generating a highly persistent scent-mark. On the other hand, species inhabiting wet, humid conditions produced highly aromatic and low-weight secretions containing numerous different compounds. This chemical mix probably creates a volatile-rich signal that can be used for long-distance airborne communication.

While we cannot deny that these findings of convergent evolution in the design of chemicals signals are fascinating, some would say this outcome is not unexpected.

“[…] a cadre of scientists has taken the […] view, that convergence is the expectation, that it is pervasive, and that we should not be surprised to discover that multiple species […] have evolved the same features to adapt to similar environmental circumstances. From this perceived ubiquity, the scientists draw a broader conclusion: evolution is deterministic, driven by natural selection to repeatedly evolve the same adaptive solutions to problems posed buy the environment. — J. Losos (Improbable Destinies, p. 33)

Nonetheless, I am confident to state that using by far the largest comparative dataset amassed to-date to examine patterns of chemical signal divergence, we have provided strong evidence for a significant relationship between chemical signal design and prevailing environmental conditions, which may results from differential selection on signaling efficacy (Baeckens et al. 2017).

T-shirt Contest for Anolis Symposium VII Now Open!

By Melissa Kemp

On September 22, 2017

In All Posts

T-shirt from the 1999 Anolis symposium at Penn State

As you may have heard in the announcement of the 7th Anolis symposium, we are searching for the official t-shirt design! You’re all surely aware of how talented our community is, as exemplified by past photo and poetry competitions, so we are asking you all to submit your best designs! A panel of discerning anolologists will choose the winning design, and the winner will receive glory, bragging rights, and pride in knowing that their artwork will be memorialized in t-shirt form for all to admire (the winner will also receive a free shirt).

Designs must meet the following criteria:
Style: line drawings are preferred
Size: Must fit neatly into a 8” x 8” square
Number of colors: 2
File type: high-quality .jpg, .png files or illustrator files.

Also, lease be aware that we may have to make minor alterations to the winning design in order for it to fit onto a t-shirt.

Front of the shirt from the 2009 symposium

Please send all submissions to anolis2018@gmail.com with the subject line “anole t-shirt contest” by October 20, 2017!

Stay tuned for the winning design, and may the odds be in your favor! We look forward to seeing all of your submissions. For more information on the symposium, be sure to check out the official page!

p.s. Who still has a t-shirt from the 1989 meeting? Photo?

Back of the t-shirt from the 2009 symposium at Harvard

Request for Anolis aquaticus Photos and Sightings

By Lindsey Swierk

On September 20, 2017

In All Posts

Photo by Anolis aquaticus from wildherps.com.

Hello anole enthusiasts!

A quick note and a request from your Anolis aquaticus correspondent. Our new paper on stress-related body color brightening in Anolis aquaticus was recently selected as Editor’s Choice in the Canadian Journal of Zoology. In it, we document a genus-atypical direction of color change following exposure to a stressor, possibly related to optimizing camouflage in the water anole’s unusual habitat. Enjoy!

We are embarking on a new research direction with these wonderful watery critters. In our early stages of surveying, I’d like to ask for your help.

We are exploring morphological and behavioral variation across the water anole’s range to explore several hypotheses related to coloration, habitat lighting, temperature, and stress.
For example, dewlap coloration seems to be fairly variable: water anole dewlaps from our sites at Las Cruces Biological Station are red-orange (left), but at Osa the dewlaps are much yellower (e.g., screen shot taken from Brave Wilderness’s video* on the water anole, right).
jennet Osa

In addition, we’re also interested in knowing a little more about water anoles in the riparian zones that are found in otherwise deforested tropical pasture lands. We’ve put together a map of all known collection sites of museum specimens and published studies (sites shown without exact coordinates in the interest of species’ protection; grey sites are approximate).

You can help by sharing with us your photographs of water anoles (dewlaps are of special interest, but any photographs would be appreciated) and/or locality data** of Anolis aquaticus sightings or collection. Locations of sightings in pasture/agricultural areas are especially needed!

Lindseyns @ gmail.com
Lindsey.swierk @ yale.edu

Thank you for your help!

*A very enthusiastic group called Brave Wilderness posted a video about their search for the “mysterious” water anole. I have mixed feelings about it and its less-than-perfectly-accurate information, but it certainly captures kids’ imaginations!

**To keep this charismatic species safe and help prevent poaching, please send any GPS coordinates to me directly rather than posting them publicly.

Anolis garmani in South Florida; 11 June 2016

By Janson Jones

On September 18, 2017

In Anole Photographs, Introduced Anoles

Anolis garmani, the Jamaican giant anole; Miami-Dade county, Florida (11 June 2016, Nikon D7100).

Every year, I try to get down to south Florida at least a couple of times to stomp around for non-native anoles and other lizards. To date, I’ve only managed to find and photograph three Jamaican giant anoles, Anolis garmani, in south Florida — three individuals over two specific visits to the Miami-Dade area. The first two were in June of 2016, and the third (and largest) was in August 2017. The garmani featured here was the second wee giant from that first visit.

I’d been anxious to photograph garmani for quite some time, and we (James Stroud, Eric-Alain Parker, and myself) were more than a little jazzed to get our hands on both of those garmanis. A. garmani was quite high on my holy-grail list for south Florida non-natives, and, whereas this garmani may have been lacking in the “giant” aspect, it certainly didn’t lack in its color play. The lead image above through the following three profile shots were all taken within the span of two minutes (1:26pm through 1:28pm):

Anolis garmani [B], 11 June 2016 (1)

Anolis garmani [B], 11 June 2016 (2)

Anolis garmani [B], 11 June 2016 (3)

When we first spotted this particular wee giant biding its time in the plenty of existence, it was sporting the familiar bright emerald green:

Anolis garmani [B], 11 June 2016 (5)

Minutes later, in hand and not too thrilled about its potential lifespan outlook, the colors shifted quite dark…

Anolis garmani [B], 11 June 2016 (4)

…and then, more comfortably, back to a more-emerald green base:

Anolis garmani [B], 11 June 2016 (6)

Looking down from above, it had a fairly typical anole head from a central Floridian’s perspective…

Anolis garmani [B], 11 June 2016 (8)

But looking up from below? An extremely awesome speckled circus of contrast and patterning:

Anolis garmani [B], 11 June 2016 (7)

Yeah, this was one hell of a lizard to get to work with. Actually, all three of them were. I’ll save the bulk of photographs for the other two individuals for a future time, but for quick reference, here’s a single shot of each:

This is the first individual we found on June 2016:

Anolis garmani [A], 11 June 2016

And here’s the much-larger male Eric and I tracked down (and almost caught) in August 2017:

Anolis garmani, 06 August 2017

~ janson

Are Brown Anoles in Florida Really Driving Green Anoles to Extinction III: A Post-Irma Update

By Ambika Kamath

On September 15, 2017

In All Posts

Almost anyone who cares about anoles in the US is aware of the hypothesis that the arrival of brown anoles (Anolis sagrei) into Florida has driven declines in the abundance of native green anoles (A. carolinensis). Though there is certainly evidence that this hypothesis may be valid to some extent, we’ve previously wondered if the decline is as severe as folks seem to think it is. Have green anoles instead simply shifted to higher perches where we don’t see them as often? An informal mark-recapture effort conducted in Gainesville FL suggests that green anoles may in fact be quite abundant, and based on the evolutionary history of green and brown anoles across their ranges, we do in fact expect green anoles to shift upwards where they co-occur with brown anoles.

Green anoles, increasingly elusive in Florida

We now have yet another piece of evidence that green anoles may be thriving at the tops of trees , just out of sight. Because of Hurricane Irma, which wreaked havoc across Florida last week, many of those tree canopies have fallen to the ground. And Miami herpetologist Steven Whitfield reported yesterday seeing “more green anoles in the past two days than I have in the two months before that.” This observation was confirmed by other local biologists as well, in comments on Whitfield’s initial Facebook post that said “Green anoles are all over the place. Seems they were around up in the canopy, but now the canopy is on the ground so they’re easy to see.”