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The Joint Meeting of Ichthyologists and Herpetologists (JMIH) kicked off here in New Orleans yesterday. In the morning, Jonathan Losos got started with the first of many anole themed talks. Jonathan gave one the plenary addresses as the Herpetologists’ League’s “Distinguished Herpetologist” of 2016. As such, he joins a long list of accomplished herpetologists, including the first recipient of the honor in 1981, the great anole biologist (and Jonathan’s undergraduate advisor) Ernest E. Williams.

In Jonathan’s talk entitled “Known knowns and unknown unknowns: herpetological progress in fits and starts”, Jonathan started by paying homage to Ernest Williams. He managed to find slides from Ernest’s 1981 plenary address in which the perception at the time of anole biology was compared to a well-built building. All there was to know about anoles was known… or so people thought. In reality, the building looked more like this:

E.E. Williams slide on the state of anole knowledge from 1981

The metaphorical building at the time was in fact only partially built, with bits and pieces of different areas more complete than others. Jonathan’s talk focused on the fact that despite over 3 decades of progress, so much is still unknown about anoles, including basic natural history of many species. And so Jonathan shared with us a few stories highlighting some surprising anole findings and remaining unknowns, featuring the work of his students from the past 20 years:

Genetic diversity:
One surprise finding over the past 30 years is that several anole species have deep mitochondrial splits. Anolis oculatus, for example, on the tiny island of Dominica has 4 distinct lineages with as great as 10% mtDNA divergence (Malhotra and Thorpe 2000)! And they aren’t the only ones. Rich Glor and Jason Kolbe really broke this story open with their analysis of several anole species showing multiple mitochondrial lineages for each (Kolbe et al. 2007). This brings into question our estimates of diversity. If every species is actually 4+ species, have we underestimated diversity?

New Species:
According to Jonathan, it seems that the “dawn of anole discovery” peaked in the 1970’s – the last very distinctly different anole was discovered nearly 40 years ago. And yet just last month, Luke Ma hler et al. published a record of a new species of anole discovered on the island of Hispaniola! Hispaniola has been intensely studied by anole biologists, making this all the more surprising. In honor of the naturalist that found the species in the wild, the authors named the new species Anolis landestoyi. This new species has a striking appearance, similar to a chameleon and to the Cuban “false chameleons” (Chamaeleolis clade of anoles), and brings up the question of whether there might be a seventh ecomorph.

Anolis landestoyi, photo by D. Luke Mahler

Territoriality:
Highlighting the work of two other Losos Lab members, Alexis Harrison and Ambika Kamath, Jonathan talked about how little we know abut anole territoriality. Conventional knowledge says that males maintain polygynous territories and don’t move too far. But Ambika has shown in her dissertation work that male Anolis sagrei actually move quite a bit, and Alexis has shown that male Anolis carolinensis mate with females on opposite sides of their site, not just nearby females! In general, Jonathan commented that there is a large amount of work to be done still on social behavior in anoles.

Anolis proboscis (photo by Luke Mahler)

Basic Biology:
Jonathan talked about the Anole Annals darling, Anolis proboscis. This understudied species sports a large nasal projection of unknown purpose. This odd species was thought to be extinct for many years until it was “rediscovered” only a few years ago. While sexual selection seems like an obvious cause of this structure (the females do not possess horns), its not clear what the males use it for. The obvious hypothesis, that it is used for male-male combat, is easily refuted by video demonstrating that this structure bends easily. Moreover, it appears that they can bend the horn, as seen in this video! The mystery of this structure’s function remains unsolved.

Finally, Jonathan talked about an interesting anecdote: that Anolis agassizi from Malpelo island seems to have a strange preference for the color orange, as described by Rand et al. (1975). Jonathan described a recent test of this preference replicating the Chuckles candy experiment (the experiment has been described here on Anole Annals) and confirming that this species does, in fact, prefer the colors orange and yellow when it comes to Chuckles candy. He also showed a video of A. agassizi swooping in from afar to eat (attack?) an orange. Why are they so attracted to this color? Sounds like a project waiting to happen.

In short, Jonathan emphasized these two main points:
1. Natural history information is key; you need to know basic aspects of biology and natural history to dig into the deeper questions.
2. There are so many questions to be answered about anoles still, and room for all who want to join the party.

Resolving Phylogenetic Uncertainty in Anoles Using Treescape

By Michelle Kendall

On July 5, 2016

In All Posts, Lizards in an Evolutionary Tree

It’s an all-too-common situation: you would like to infer a phylogeny for a set of organisms, you try a few different methods and you end up with many different trees. Even with the most careful choice of software, settings, tree priors, and the most beautifully converged Bayesian posterior likelihood, you may find that the maximum clade credibility (MCC) tree has low posterior support for certain deep clades.

Anole MCC tree with posterior supports, from Geneva et al. [1]

Tree inference is very complicated, particularly for species trees, and is hampered by factors which include the vast size of tree space, conflicting signals from different genetic loci, confusing signals from convergent evolution, and non-tree-like evolution (recombination, hybridisation, etc.). Geneva et al. experienced just this sort of difficulty when they performed a comprehensive Bayesian phylogenetic analysis of the distichus group of trunk ecomorph anoles [1]. Their MCC tree is reproduced here, and the posterior support values show uncertainty in the branching structure of various deep clades. There are many combinations of ways to resolve these uncertain splits. We wanted to see which alternative trees were supported by the data.

In our recent paper [2] we present a method for handling phylogenetic uncertainty and incongruence. It takes a set of trees and “maps” them into a simple plot where similar trees are grouped together and more different trees are placed further apart. Where many similar trees are clustered together, contour lines indicate the density of points in that region. We began the development of our method theoretically, making sure we had designed a robust mathematical definition for tree distances which would correspond to biological intuition and lend itself to good quality map projections. Then, working closely with biologists, we fine-tuned our method for specific applications with real data and wrote the R package treescape [3] so that anyone can use it – there’s even a handy web app version which requires no knowledge of R.

treescape MDS plot: each point represents a tree, and proximity of points represents similarity of trees. 1000 trees are plotted here, many identical, so contour lines indicate density of points. Colours correspond to clusters of similar trees.

treescape MDS plot: each point represents a tree, and proximity of points represents similarity of trees. 1000 trees are plotted here, many of which are identical, so contour lines indicate the density of points. Colours correspond to clusters of similar trees.

When we applied our method to the trees from the analysis of Geneva et al. [4], we found that there were distinct “clusters” of equally likely tree topologies. It is reassuring that the MCC tree belongs to the largest of these clusters (highlighted on the plot by a yellow triangle), but clearly it cannot represent all of the likely tree shapes on its own. By taking a representative tree from each of the six or so tight clusters, we obtain a more thorough summary of the range of trees supported by the analysis. Such representative trees, taken from the geometric “centre” of each cluster, are credible summary trees with real branch lengths, unlike trees from other summary methods which can suffer from strange behaviour such as negative branch lengths.

We find that there are alternative placements of certain taxa, particularly the ocior, distichus, dominicensis2 clade, and (in our supplement) we explore some of the knock-on effects of using these different tree shapes when analysing the evolution of the anoles, specifically their geographical origins and transitions in their dewlap colour. For instance, we show here a representative tree from each of two different clusters on the map. The trees support ocior, distichus, and dominicensis2 being more closely related to anoles from the East of Hispaniola (the North paleo-island) or the South-West (the South paleo-island) respectively. Both evolutionary histories are supported by the data; in the absence of further research, there is no reason to exclude any of the alternative representative trees identified by our method.

Representative tree from top left cluster

Representative tree from top right cluster

[1] Geneva, A. J., Hilton, J., Noll, S. and Glor, R. E. (2015). Multilocus phylogenetic analyses of Hispaniolan and Bahamian trunk anoles (distichus species group). Molecular Phylogenetics and Evolution, 87:105-117.

[2] Kendall, M. and Colijn, C. (2016) Mapping phylogenetic trees to reveal distinct patterns of evolution. Molecular Biology and Evolution, first published online June 24, 2016. DOI: 10.1093/molbev/msw124

[3] Jombart T., Kendall M., Almagro-Garcia J., Colijn C. (2015). treescape: statistical exploration of landscapes of phylogenetic trees. R package version 1.9.17.

[4] Geneva A. J., Hilton J., Noll, S. and Glor, R. E. (2015). Data from: Multilocus phylogenetic analyses of Hispaniolan and Bahamian trunk anoles (distichus species group). Dryad Digital Repository.

Anole Hunting in Southern Nicaragua

By Paul Freed

On July 4, 2016

In All Posts

Figure 1. Anolis cupreus.

Spending two weeks searching for amphibians and reptiles along Nicaragua’s southern border proved very successful for a band of nature enthusiasts. Accompanied by my primatologist wife Barbara, fellow herpetologist, Joe Furman and his daughter Sadie, and our expert guide Lenin, we visited several nature reserves hoping to observe as many species of herps as possible. Our journey began in Ticuantepe, at the Montebelli Reserve, where we spent our first night searching the forest for any creatures that were out and about. The rainy season had not yet begun and the lack of rain resulted in a paucity of herpetological sightings. We did manage to find a few frogs (Smilisca baudinii and Scinax staufferi), a small fossorial snake (Enulius flavitorques), as well as a sleeping Copper Anole, Anolis cupreus (Fig. 1). Our stay here was brief and the following day we were on our way to the Ecological Center of Los Guatuzos, near the town of Papaturro.

Figure 2. Anolis limifrons.

The forests here were much more expansive and bordered the Papaturro River. and as a result the abundance of amphibians and reptiles was significantly greater. The river, which ran immediately in front of our accommodations, contained large numbers of Spectacled Caimans (Caiman crocodilus), ranging from yearling size to two meter long adults. At night their glowing orange eyes could clearly be seen scattered throughout the waterway like dim headlights on a busy thoroughfare. On our first night’s outing we observed more than a dozen species of amphibians and reptiles including the iconic Red-eyed Treefrog (Agalychnis callidryas), Fleischmann’s Glass Frog (Hyalinobatrachium fleischmanni) , the giant Smoky Jungle Frog (Leptodactylus pentadactylus), Clouded Snail-eating Snake (Sibon nebulatus), and two species of anoles: Slender (Anolis limifrons Fig 2.), and the Neotropical Green Anole (Anolis biporcatus Fig 3.).

Figure 3. Anolis biporcatus.

Figure 4. ???.

The following night we came upon an almost white-colored male anole (Fig. 4) sleeping on a leaf some two meters above the ground that we couldn’t readily identify. We realize that many anole species have different body color and patterns at night than they do during the day, so we decided to check the dewlap to see if that might help us render a positive identification. The dewlap was mostly light in coloration with several dark green spots scattered throughout (Fig. 5). Despite this characteristic coloration, the species remained unknown to us.

Fig. 5 dewlap of unidentified white anole

Figure 5. Dewlap of unidentified white anole in Fig. 4.

Figure 6. Second unidentified white anole.

Fig. 7 dewlap of second unidentified anole

Figure. 7 dewlap of second unidentified anole.

Shortly after finding this anole, another unidentified white anole was observed (Fig. 6) however, this one had a bright orange-colored dewlap (Fig. 7).

Our final destination took us up the Rio Bartola to the Reserva Naturale Indio Maiz. Like our previous sites this one had large, expansive forests with no other visitors anywhere in the vicinity. Fortunately, the rains had now begun and we were treated to a greater diversity of wildlife including more than two dozen species of amphibians and reptiles. Perhaps due to the onset of the rains or maybe because this reserve is naturally abundant in snake fauna, we ended up seeing more than a dozen serpents in just a few days time. Most notable among them was the seldom seen White-headed Snake, or Panda Bear Snake (Enuliophis sclateri Fig 8), a small fossorial species known from only four other individuals from Nicaragua.

Figure 8 Enuliophis sclateri, White-headed Snake

Figure 9. Anolis capito

Six species of anoles were found here including the mossy-looking Anolis capito (Fig. 9), the Slender Anole (Anolis limifrons), the Lion Anole (Anolis lionotus Fig. 10), of which several were observed during the day on rocks in a shallow stream as well as at night on thin branches overhanging the waterways, a species we were unfamiliar with but which our guide identified as Anolis quaggulus (Fig 11).

Anolis Photos from Cuba: ID Help Needed

By Vladimir Dinets

On July 2, 2016

In All Posts

I spent a few weeks on Cuba in February-March, and photographed a bunch of different anoles, but I have no way of identifying them. I put all photos on one page with very tentative captions. I’ll appreciate any comments/corrections.

Here are some of the uncertain ones:

Brown Anoles Invade New Orleans: What Will Happen to the Greens?

By Jonathan Losos

On July 2, 2016

In All Posts

Just in time for the American Society of Ichthyologists and Herpetologists meeting in New Orleans next week. From the New Orleans Advocate:

Are New Orleans’ green anoles being ousted by drab invaders?

Advocate staff photo by HILARY SCHEINUK — A green anole peers out from hiding in a fern as Independence Park’s Botanical Gardens come back to life after a band of thunderstorms moved through the area Wednesday morning, April 27, 2016.

BY R. STEPHANIE BRUNO| SPECIAL TO THE ADVOCATE

July 1, 2016; 5:05 p.m.

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It flashed across the walkway like a lightning bolt, so fast that Bob Thomas had to do a double take. In that split second six months ago, he knew they had finally arrived.

“I’d been waiting for them to arrive in my neighborhood in Metairie. What I saw moved too fast for what we’re used to around here,” said Thomas, a herpetologist who taught at Loyola University and served as the founding director of the Louisiana Nature Center.

“It could only be one thing: a brown anole, Anolis sagrei.”

You’ve seen them — the speckled brown lizards that come out of nowhere and streak across the sidewalks. They travel in hordes — tiny, large and everything in between. Careful! You’re liable to step on them if you don’t pay attention.

Thomas’ neighborhood is far from being the first to experience an invasion of brown lizards. But where did they come from? Why are they so plentiful?

“Brown anoles are an invasive species, not native to the United States,” said David Heckard, curator of reptiles and amphibians at the Audubon Institute. “They are natives to Cuba and the Bahamas and first appeared in the U.S. in Florida. From Florida, they’ve been slowly expanding their range across the Gulf Coast. They’re aggressive and competitive and have even been spotted in Taiwan. They hitch rides on plants and are spread inadvertently by plant nurseries.”

The brown anole looks a lot different than the sleek green lizards we grew up with here in New Orleans (Anolis carolinensis). Generally, A. sagrei has a more compact physique and a shorter skull. A prominent hump appears where muscles attach at the back of the skull. When the brown anole extends its orange and red dewlap (the skin flap below its chin), it looks ferocious, indeed.

By contrast, the green anole looks far friendlier, even when its rosy-hued dewlap is extended. Native to the southeastern parts of the United States (although DNA studies suggest they originated in Cuba and came here a couple of million years ago), green anoles range as far north as North Carolina and as far west as Austin, Texas. They have delicately shaped heads and long, lean bodies. They were once plentiful in New Orleans, but sightings are becoming rare.

So, are the brown anoles killing off the green anoles, fighting over territory and winning? Consuming the green anole’s food supply?

“The theory is that the brown anoles are displacing the green anoles but not necessarily replacing them,” Heckard explained. “It’s believed that green anoles are more arboreal than brown anoles, which are more terrestrial. So, green anoles are being pushed to higher elevations — up into trees and the like. It may seem as though there are fewer of them, but they’re present — you just can’t see them hiding in the leaves and up in trees.”

Simon Lailvaux, a professor in UNO’s department of biological sciences, has studied anoles since working on his doctorate and supports the displacement theory.

“In the Caribbean, where there are dozens of species of lizards, they have learned to partition the habitat and have evolved to live in a specific part of it,” Lailvaux explained. “Green anoles there are trunk/crown inhabitants, whereas brown anoles are trunk/ground inhabitants. Over the millions of years that green anoles have been in the United States, they evolved to be able to occupy the ground because they didn’t have any competition for it. So, the relatively recent invasion of brown anoles has simply forced them back up into trees where they originally lived.”

Are we sure about that? Is anybody counting?

“How can you count green lizards way up on tree trunks and in the leaves at the crowns of trees?” answered Lailvaux. “You can’t.”

According to all three scientists, both types of anoles eat the same things: insects and other invertebrates. There are plenty of those to go around here, so it’s improbable that the green anole’s food supply is in jeopardy. Luckily for the green anoles, they may have a significant competitive advantage over the invaders.

“Brown anoles are cold sensitive and can survive only in a limited temperature range. That means the population of brown anoles crashes when we get a hard freeze, and it takes forever for their numbers to recover,” Lailvaux said. “The green anole, on the other hand, has evolved to be able to withstand lower temperatures, so they won’t be bothered by a freeze. We’re seeing, though, that it is taking less and less time after a freeze for the brown anoles to recover, which means they’re already beginning to adapt.”

The mild winters of the past few years may account for the explosion in the visibility of the brown anoles. But if A. carolinensis is being replaced (not merely vertically displaced) by A. sagrei, it would be a case of a native species dying out because an invasive species outcompetes it. Should we be looking into how to reverse that trend?

“The green anole may be a nostalgic favorite, but we don’t know yet what impact the proliferation of the brown anole will have on it or on other species. The sense is, however, that it won’t be wonderful,” Thomas said.

We know too well what an invasive species can do: Witness the nutria. By consuming the marshes, the animals not only reduced storm surge protection for our area but caused the demise of other species that called the marshes home, Thomas pointed out. Without further study, there’s no way to predict if the success of the brown anole could be similarly dire for the green anole and for biodiversity.

Anole Fabric

By Jonathan Losos

On June 30, 2016

In All Posts

anole fabric 2

I’m not sure I like anoles being referred to as “ditsy,” but here’s a great opportunity to create lovely anole-wear, not to mention anole curtains, anole quilts and all kinds of other anoliana.

anole fabric

Green Anole Hunting Brown Anole–Foiled

By Jonathan Losos

On June 27, 2016

In All Posts

And he’s not happy about it! Photo by Karen Cusick

Details on Daffodil’s Photo Blog.

Nocturnal Behavior in the Green Anole

By Ambika Kamath

On June 25, 2016

In All Posts

I’m currently reading a 274 page tome called “The Biology and Biodemography of Anolis carolinensis” by Robert E. Gordon. Dating back to 1956, this impressive piece of scholarship is Gordon’s Ph.D. thesis. Gordon collected the bulk of his data in biweekly nocturnal surveys of the demography and spatial ecology of two populations of green anoles. The surveys continued for over a year, and consequently, this document is filled with insights into these lizards’ ecology.

One sentence that caught my attention was this, from page 195:

Anolis activity is primarily diurnal, although movement and feeding were observed at night under conditions of bright moonlight.

We’ve had observations of anoles feeding at artificial lights before, but have any of you night-owl herpers observed something similar under natural light?

A figure from Gordon (1956). Can we bring back this elegant asymmetric bar graph plotting style?

A figure from Gordon (1956). Can we please bring back this elegant asymmetric bar graph plotting style?

Evolution 2016: Polar Vortex Revisited

By Kristin Winchell

On June 23, 2016

In All Posts, New Research

Shane Campbell-Staton giving his talk at Evolution 2016

We’ve heard about the effects of polar vortexes here on Anole Annals before. The infamous 2013/2014 event brought record-breaking snow and low temperatures to the Southern U.S., leaving people and animals both a little chilled. This created the perfect opportunity for Shane Campbell-Staton to investigate the effects of such extreme events on thermal tolerance of the native Carolina Anole, Anolis carolinensis. Shane also spoke about this at SICB earlier this year, and AA contributor Martha Muñoz covered the talk pretty thoroughly here on Anole Annals. Nevertheless, I’ll summarize some key points here in case you missed it.

An unlucky lizard during the polar vortex snow storms in the South.

Shane got lucky in the sense that he had measured thermal tolerance in August 2013 for populations affected by the polar vortex, 5 months before the event. Typically, the cold arctic air is tightly constrained around the North pole, but periodically the boundaries weaken and the cool air expands southward. These events are not regular, so Shane had no idea one was coming that winter or that it would extend so far south. It was serendipitous that his study populations, 3 in Texas and 1 in Oklahoma, were impacted by the extreme weather event. This species, particularly in the Southern portion of its range, is not used to low temperatures and reports came in of anoles dying off during the storm.

Air temperatures for January 5-7, 2014, compared to the 1981-2010 average. Map by NOAA Climate.gov

So Shane returned in August of 2014 and sampled again, curious as to how this cold impacted thermal tolerance. He found that tolerance to low temperatures, measured as critical thermal minimum (CTmin), was lower in some populations after the event! Even more, the difference was greatest in the Southernmost population (Brownsville, Texas). Shane returned again in the fall of 2014 to see if this effect persisted or if it was simply a plastic response to the event. He found that the populations sampled in 2014, and presumably their offspring, still had lower critical thermal minimums. This result suggests that the extreme cold weather had caused an evolutionary shift in cold tolerance via natural selection: only the animals that could tolerate the cold temperatures survived and passed on their cold-tolerance genes. Shane went on to conduct a common garden study to verify that the trait was not simply a plastic response. He found that the lower CTmin persisted in lab-reared animals: strong evidence that these shifts had a genetic basis.

Lastly, Shane looked at the functional genomics of cold tolerance. Using liver tissues to obtain transcriptomes (representing expressed genes), he found several gene modules associated with thermal tolerance including some associated with respiratory electron transport chain, lipid metabolism, carbohydrate metabolism, and angiogenesis/blood coagulation. He also found that the gene expression patterns in the Southern populations affected by the storm resembled the Northern populations that more regularly experience cool temperatures, indicating a common genetically based adaptive response across populations.

Evolution 2016: Using Genomic Tools to Explore Selection and Evolution in Anolis Species

By Sofia Prado-Irwin

On June 21, 2016

In All Posts

By Pavitra Muralidhar

Adaptive radiation is one of the most intriguing processes in evolutionary biology, and anoles are one of the well-studied examples of this process. Anoles have diversified into over 400 species across the Caribbean and Central America, and contain a multitude of highly divergent morphological and behavioral types. Thanks to an impressive history of research on this clade, we now know quite a lot about the phenotypic aspects of this adaptive radiation; however, we still don’t have a good understanding of the genetic mechanisms underlying this diversity of form, physiology, and behavior. The recent advent of next-generation sequencing, and thus the ability to quickly sequence entire genomes of non-model organisms, offers a tantalizing possibility for investigating the genetic basis of adaptive radiation in Anolis.

Tollis et al., in a lightning talk at Evolution, take advantage of these new genome-sequencing techniques to approach the genetics of adaptive radiation in Anolis. To understand the genetic mechanisms underlying the adaptive radiation of anoles, they preformed de novo genome sequencing on three Anolis species (Anolis frenatus, Anolis apletophallus, and Anolis auratus), chosen to capture different sub-groups of the Anolis phylogeny. With these data, and the published genome sequence of Anolis carolinensis, they looked for patterns in the rate of evolution compared to other vertebrate groups. They also looked within the Anolis genome to detect specific genetic regions associated with selection across the anole radiation.

Tollis et al. found that, in general, anoles appear to have a high rate of molecular evolution for a vertebrate species, which may parallel the high rate of phenotypic evolution seen in this clade. In addition, Tollis et al. looked for signatures of selection across the four Anolis genomes and identified regions associated with reproduction, olfactory reception, and limb development. This last category is of special interest, given that anoles are notorious for changes in limb morphology between species and that limb morphology is one of the key components of ectomorphs in the Greater Antilles. Tollis et al. have provided a great example of using new genetic tools to approach fundamental questions about the mechanisms underlying adaptive radiation.