All posts by Jonathan Losos

About Jonathan Losos

Professor and Curator of Herpetology at the Museum of Comparative Zoology at Harvard University. I've spent my entire professional career studying anoles and have discovered that the more I learn about anoles, the more I realize I don't know.

Take That Geico: Anole Eats a Gecko

Scott Trageser posted this photo on Herpnation of Anolis leachii eating a gecko in Codrington, Barbuda. Here’s a few more details he sent while travelling in Madagascar: “The story was, I was photographing the gecko for a distribution note and the A. leachii came down and grabbed before I could even pull the shot off! The leachi would stay high in the trees so despite being large, we seldom saw them.”

Note: it is proper to spell leachii with two “ii”‘s

Anole Calendars Now 30% Off. Watches, Too!

anole calendar 1 front

Your frugality has paid off! Through Wednesday, is having a 30% sale. That’s $15 per calendar. Stop missing appointments and get your calendar today. Code: SEMIYEARSALE

anole calendar 2

While you’re shopping on zazzle, check out the Anole Annals store there. All custom items are on sale for 30% off, including the ecomorph line of watches, ties, playing cards and more.


50% Off Anole Calendars

anole calendar 1 front

That’s right, the sale you’ve putting waiting for on 50% off calendars through Monday. That’s $11 per calendar. You can’t afford not to buy one…or two. Use the code SAVEAFTRXMAS.

anole calendar 2

While you’re shopping on zazzle, check out the Anole Annals store there. Everything’s on sale for at least 20% off, including the ecomorph line of watches, ties, playing cards and more.


New Paper on the Introduced Reptiles and Amphibians of Cuba

cuba intro herps

At last we’ve found a place in the Caribbean that Anolis sagrei hasn’t invaded: Cuba! Because, of course, A. sagrei is native there, as well as 63 other species of anoles. In fact, there are no introduced anoles on Cuba, which is quite unusual. There are, however, a number of other herps that have invaded there, as a recent paper in Herpetological Conservation and Biology by Borroto-Páez discusses. Here’s the abstract:

The number of introductions and resulting established populations of amphibians and reptiles in Caribbean islands is alarming. Through an extensive review of information on Cuban herpetofauna, including protected area management plans, we present the first comprehensive inventory of introduced amphibians and reptiles in the Cuban archipelago. We classify species as Invasive, Established Non-invasive, Not Established, and Transported. We document the arrival of 26 species, five amphibians and 21 reptiles, in more than 35 different introduction events. Of the 26 species, we identify 11 species (42.3%), one amphibian and 10 reptiles, as established, with nine of them being invasive: Lithobates catesbeianus, Caiman crocodilus, Hemidactylus mabouia, H. angulatus, H. frenatus, Gonatodes albogularis, Sphaerodactylus argus, Gymnophthalmus underwoodi, and Indotyphlops braminus. We present the introduced range of each of the 26 species in the Cuban archipelago as well as the other Caribbean islands and document historical records, the population sources, dispersal pathways, introduction events, current status of distribution, and impacts. We compare the situation of introduced herpetofauna in Cuba with that in other Caribbean islands. We also document impacts, areas of missing information, and possible directions for future research. The paper contributes a systematic review as well as new knowledge for national and international agencies and databases. This information is critical for use in conservation, management, and eradication. Additionally, it alerts management authorities as to specific pathways of introduction for proactive action, which may be used to avoid potential introductions.

How R Has Changed How We Look at Principal Component Analyses

A typical table reporting PCA results that I randomly trawled from the internet

This post isn’t really very anole-specific, but because lots of studies of anoles use principal component analyses, I think it’s at least tangentially relevant.

PCA is a way of to reduce the variation in a data set to a few dimensions by constructing new variables that emphasize variables that are highly correlated with each other. I won’t go into the details of the method here, because Ambika Kamath explains all in a post she wrote on her blog a while back.

What I want to mention here is how we interpret these new statistical axes. Back in my day, computer programs spit out a matrix of numbers like the one above, which we called “loadings.” These values represent how strongly each variable was correlated with each of the new axes. So, for example, in the table above, values for PCA axis one correlate most strongly with “fats and oil” and “animal protein” content and most weakly with Vitamin B1.In other words, the regression line determining the PCA (a PCA axis is a linear regression of all the variables), was determined the most by fats and oils and animal protein and the least by Vitamin B1.

Now, everyone uses the computer program R to conduct PCAs, and R, too, spits out “loadings.” But those are not your father’s loadings (or my loadings). Rather, those values are the coefficients of the new equation that defines the PCA axis. Thus, in the example above, hot dogs that scored high on PCA 1 would have the largest (positive or negative, depending on size) fat and oil and animal protein content. Back in the day, we could also access those values, but we called them “coefficients.”

Does this really matter? Only to the extent that what much of the literature used to call “coefficients” is now called “loadings” and what used to be called “loadings” apparently isn’t routinely spit out by R. And, more importantly, most R users are completely unaware of the switcheroo.

Ambika did a very preliminary analysis to see whether the values of coefficients (new “loadings”) and correlations (old “loadings”) are very different. Her tentative conclusion is that they aren’t, so maybe this doesn’t matter much, but it might be worth looking into more.

Reflections on the Shape of Lizard Eggs and Life

Elsewhere on Anole Annals, Silas Ginn responsed to a question about what shape anole eggs have. I believe his response deserves a wider audience and so am putting it up here as its own post:

Indeed, anole eggs are long and skinny when they’re laid. But due to their leathery flexible skin, they can expand like a balloon and will grow with age and moisture. I’ve only got experience with Knight anoles, green anoles and probably four or five types of different brown anoles, but they’re all about the same – except that the Knight anoles HATCH at the same size as a green or brown anole.

As for hatchlings of green or browns, they’re so tiny it’s just remarkable! My old workplace was “infested” with a few species of geckoes (in Calgary Alberta, Canada – of all places!) and the baby geckoes popped up all over the place, especially in the filing cabinets where they obviously preferred to lay their eggs between pieces of paper, due to their being hidden & protected so well.

But yeah, at one point I brought in some house-plants – this was a huge ware-house complex where we ran an aquarium fish and reptile importer supplying Western Canada’s pet-shops, plus an outlet to the public, and a custom tank building shop in the back, quite a lot of space and amounting to more than 700 aquariums all told – and the whole place with 35-40ft ceilings and kept at upwards of 30-degrees Celcius all of the time, naturally humidity was such that it actually RAINED inside of the place on a regular basis – a problem in that it brought down the decades-old asbestos spray-on fire retardant insulation material from the ceilings – but we had some very nice sky-lights as well, if it had been kept up better it would’ve made a fantastic space well I mean really fantastic ’cause I loved it even WITH the dust and cockroaches ha-ha.

ANYWAY yeah I brought in some house-plants to liven the place up – should’ve left ’em when I moved on, ’cause they’ve all died since. There was a huge Munstera deliciosa “swiss-cheese plant” which I potted up on top of overhead wooden beams that had been there for decades, as some type of over-head system for a belt-driven power supply back when it was a SWEAT SHOP and then a SLAUGHTER HOUSE for chickens, yuck – we kept the beams for our water supply and oxygen for bagging fish, plus running heated/de-gassed tank-change water, and a master air-line gang-way for running hundreds of little valves off of for all of the little bubblers etc.

But yeah what I did with it MYSELF, was to support some house plants. And this one Munstera got HUGE – it sent out aerial roots, if you know Munstera you know the type I mean – but THESE ones got long enough that not only did they hang down the nine-ten feet to drink from a puddle on the ground beneath it (how did it know there was a puddle there?) which pooled on the polished concrete floor, from leaking tanks, over-spills from the automated tank over-flow water-change system (tanks were individual, and what looked like the typical system where everything’s on a loop, was simply a fill line from huge tanks in the back, run with big pumps only during water changes, and the over-flow went directly to the drains. Which were typically blocked up and one such drain which had been permanently blocked by our swimming-pool canister type “Sand-Filter” from our Koi pond system (several ponds ganged together on one filter) had a huge cray-fish living at the bottom of it, as though the building itself were a concrete island with a lake or ocean below it, and drain pipes more like tunnels carved by urchins or other such burrowing creatures … such was the ecosystem of the place!)

Anyway yeah, that Munstera plant threw out aerial roots that first reached the puddle on the floor, but then I began to wrap ’em around the wooden beams to keep ’em out of the way, and they kept growing down and down – once they’d got a taste of the mineral-rich water down at the bottom there was no stopping ’em! And I kept looping ’em over and over, they kept growing until this became a semi-daily task, where the roots would grow more than ten inches in one night! INSANE house-plants.

But the best of ’em all, was a 30ft Ficus tree. I had been keeping my Knight anoles in ficus trees from the very beginning, and they’d laid their eggs in the pot at the bottom, whereupon they hatched out better than any other time when I tried to incubate ’em artificially. Continue reading Reflections on the Shape of Lizard Eggs and Life

Will the Introduced Brown Anole Doom the Native Skink of Bermuda?

AA regular James Stroud aims to find out. The following is taken from the FIU (Florida International University) News:

FIU biology student James Stroud has observed a non-native species of lizard in Bermuda, a potential problem for the island’s critically endangered Bermuda skink.

A two-year conservation project studying the island’s lizard populations led to the discovery of the Cuban brown anole, a species once rumored to inhabit the North Atlantic island, but was never verified until now.

Left to right: Mark Outerbridge (Department of Conservation, Bermuda), Sean Giery and James Stroud pose in Nonsuch Island, one of Bermuda's premier protected areas that supports the Bermuda skink.

“The Cuban brown anole most likely reached Bermuda by human transport,” said Stroud, a Ph.D. student in theKenneth Feeley Lab. “These lizards hitch rides between ports as unintended stowaways amongst cargo, usually in nursery plants and building materials. Although further research is needed to confirm it, this route of introduction seems likely.”

The introduction of the Cuban anole could pose difficulties for the endangered Bermuda skink, the island’s only native lizard species. Also known as a rock lizard, the skink is listed as critically endangered in the International Union for Conservation of Nature’s (IUCN’s) Red List, the world’s authority on the conservation status of plant and animal species. According to the researchers, Cuban brown anoles excel at thriving outside of their native geographical area. The lizards can live in a variety of natural and human-made habitats, and feed on a variety of prey, potentially putting them at an advantage to other lizard species who might not be as tolerant.

The Cuban brown anole was recently confirmed to live in Bermuda by FIU biology Ph.D. student James Stroud. Photo by James Stroud

“We have discovered that the Cuban brown anole does not yet overlap its distribution with the Bermuda skink,” Stroud said. “Therefore, the potential effects of the non-native brown anole on the native Bermuda skink are currently unknown. This topic forms part of our ongoing research interests in Bermuda.”

After surveying all of Bermuda, Stroud found populations of the Cuban lizard at all life stages indicating they are thriving in the central part of the island. He also found the established Jamaican anole continues to be found all over the island, but the Antiguan anole has significantly expanded into areas where the Barbadian lizards live. The discovery was made alongside former FIU doctoral student Sean Giery and Bermuda’s Department of Conservation Services.

Originating in Cuba and the Bahamas, the Cuban brown anole is one of the most widespread lizards outside of its native area with large populations found from Florida to Texas, California, Hawaii, Costa Rica, Singapore and Taiwan. Cuban brown anoles can be found in urban environments including downtown Miami and natural environments such as the Everglades. Anoles are very diverse group of lizards and about 372 species are currently known to exist.

Stroud recently traveled to Costa Rica where he conducted the first-ever study of the Cuban brown anole’s ecology and distribution in the Central American country. He is devoting his doctoral research to studying the evolution, interactions and community patterns of Anolis lizards in the tropics.

Another Anole-Themed Wedding


Two years ago, we reported on a lovely wedding cake with green anole atop, from the nuptial festivities of Alex Gunderson and his wife Katie. Now word comes to us of another anole wedding. AA correspondent Kristin Winchell, who doubles as a grad student in Liam Revell’s lab, was married to Jonathan Zschau this past September on Nantucket Island. As the photo above attests, the wedding cake was tastefully adorned with a bride, a groom, and an anole.

Actually, it was a double wedding. A photo of the second bride, Ms. Ann Ole, is pictured below (made by the groom’s aunt).


Third Specimen of Anolis toldo Discovered

Anolis toldo. Photo by Luis Diaz.

Anolis toldo. Photo by Luis Diaz.

Luis Diaz reported on Facebook the discovery of the lizard shown above. He reports: “Anolis toldo, adult female; third individual of the species known and first specimen in the National Museum of Natural History of Cuba. The discovery of this specimen was a result of the joint expedition by the National Museum of Natural History of Cuba and the American Museum of Natural History. It was found on October 19, 2015, at night, on a tree fern in a new location (outside the only known: the plateau of El Toldo ). This is one of the few photos of the species.” The photo was tagged aat Alejandro de Humboldt National Park.

Should the Use of Subspecies Be Revived?

The last week has seen a spirited discussion of the pros and cons of splitting recognized genera into multiple, smaller genera. We’ve had 34 comments already. Check it out! And if you’re an advocate of splitting genera, that viewpoint has been getting the short end of the stick and could use more support.

As a tangent, the topic of subspecies has come up, and David Hillis has strongly argued for reviving its use. Here’s what he has to say:

First, I don’t think either species or subspecies are “clades.” Species are lineages (the branches on the tree of life). Sexual recombination among individuals results in tokogenetic relationships within species. Clades, on the other hand, are monophyletic groups of lineages on the tree of life. Rather than being defined by tokogenetic relationships, they are defined by phylogenetic relationships.

Traditionally, subspecies are geographical races of species. In other words, they are geographically distinct populations that nonetheless meet and interbreed at contact zones. Sometimes, these contact zones are very broad, as with broad-banded versus southern copperheads. If the contact zones are very narrow, and there is strong evidence that the contact zone is a genetic sink (there is no gene flow across the zone, because of strong selection against hybrids), then I agree that the two entities can be considered separate lineages, and hence species. But in many recent cases, as with the copperhead example, there is abundant evidence that the contact zone is NOT a sink, and that there is NO selection against hybrids. In this case, I disagree strongly with the authors who proposed to split these subspecies into distinct species. That is inconsistent with any lineage species concept…there is a huge area where these two forms intergrade, with no evidence of any loss of fitness. Thus, the two forms are geographical, intergrading races, or subspecies.

I think we will soon see a backlash against the splitting off of geographic races as species as well. Frank Burbrink (who was an author on the copperhead example I mentioned above) and I plan to write a pro/con article about this together, each arguing our respective points of view. Hopefully, this will re-kindle the conversation about subspecies.

Subspecies are unpopular right now because they were long abused in several ways. Inappropriate uses include (1) to describe non-geographic “varieties”; (2) to arbitrarily break up clines; and (3) to describe distinct, isolated lineages that clearly are species. But used in proper context to designate a geographically distinct race, they are certainly reasonable and often useful. They are rarely used in some groups, for several reasons: Groups like freshwater fishes have discrete ranges, so taxa don’t interbreed over broad areas. And many groups are too poorly studied to understand geographic variation. But in well-studied terrestrial groups (like herps), subspecies are perfectly reasonable and useful taxa to designate intergrading geographic races.

Taxonomic Splitting Revisited: When Should Genera Be Subdivided?

Over the last several years, ever since Nicholson et al. proposed dividing Anolis into eight genera, the topic of taxonomic splitting has periodically been discussed in these pages (for example, this post, its comments, and links to other posts).

The general question of when to split taxa recently has been revisited in several comments in AA. A week ago, David Hillis wrote:

Anolis is a valid name for a monophyletic group on the Tree of Life. It is “special” as a genus only in that the genus name is used as part of a binomial for particular species. It doesn’t make sense to change the scope and application of generic names unless the names are actually misleading about phylogeny (e.g., if Anolis were polyphyletic, then that problem should be fixed). But splitting a valid, monophyletic genus into a bunch of smaller genera, and thereby needlessly changing the names of many species, without fixing any phylogenetic problems with the existing taxon names, is not science. It is just playing around with names. If someone wants to name the groups within genera, then do so…but there is no reason to change the meaning of a existing name (or the names of the all the affected species) in doing so. That is the kind of silliness that gives taxonomists such a deservedly bad reputation among biologists.”

Elswhere, David posted a flowchart on his recommended decision-making process about whether and how to divide recognized genera:

Hillis flow chart

Ivan Prates, in line with comments he made in a recent paper on A. punctatus, then remarked:

“This seems more like a sociological matter.

During the ‘taxonomic revolution’ of the amphibians, about 10 years ago, the (perhaps?) most influential (or faster?) group was the splitter one, and their taxonomic scheme prevailed. Currently, nobody is upset about which species were once named as Bufo, Hyla or Rana. A few do care about Dendrobates – like Anolis, a sexy group with a body of dedicated investigators.

It seems that a single genus makes sense for the community that investigates dactyloid lizards more closely. On the other hand, those who deal with overwhelming levels of herpetological diversity in the tropics (waaaay beyond lizards) see benefit in more partitioned schemes, which correlate more closely to morphology and geography.

So, when we discuss names, it may be healthy not to forget about our diversity as investigators as well. About science, splitting Anolis is not science, but well, not splitting Anolis isn’t science either.”

You’re Never Going to Guess Who’s a Big Anole Lover


Rush Limbaugh, that’s who! To wit: “But I love those little lizards.  They’re anoles, actually.  I love ’em.  They’re our buddies. They eat insects and all that.”

And it turns out that Jeb Bush is just like a cat chasing an anole. Read all about it here (or listen to it here), skipping to paragraph four if you want to get to the important, mostly non-political stuff.

Redundancy in Communication Signals: Work on Anoles Anticipated Current Research Decades Ago

eew and asrIn anticipation of its sesquicentennial in 2017, The American Naturalist has solicited essays commenting on overlooked or underappreciated articles published in the journal during the past 150 years. In this month’s issue, Manuel Leal and I comment on a 1970 paper by Stan Rand and Ernest Williams on how differences among anole species in their dewlap and display behavior contain multiple signals for species-recognition. Several decades later, the importance of redundancy in communication signals has become an important area of research, but years before, Rand and Williams sketched out the important issues, as well as identifying some still-unresolved questions.

Here’s the introduction to our essay:

“Why are animal signals so complex? This question continues to attract the interest of behavioral and evolutionary ecologists. In this Countdown article, we revisit a littlea ppreciated article in The American Naturalist published in 1970: “ An Estimation of Redundancy and Information Content of Anole Dewlaps” by A. Stanley Rand and Ernest E. Williams. As part of this piece, Rand and Williams argued that signal complexity can be explained by redundancy, a mechanism by which multiple components of the signals have evolved to increase the probability of eliciting a response from an intended receiver. We highlight this work because it presents one of the earliest demonstrations of the potential benefits of applying information theory to animal communication. In addition, the study demonstrates the insights that can be gained by evaluating signal evolution at the level of the community. Even today, when both theoretical and empirical studies evaluating the potential forces leading to signal diversity have fl ourished, evaluations at the community level are extremely rare.

More generally, in the spirit of the American Society of Naturalists, we wish to emphasize that the perspicacity of Rand and Williams resulted from the fact that their ideas were ultimately derived from a deep understanding of the natural history of their study organism. In particular, Stan Rand spent substantial time in the fi eld observing lizards, including 10 months studying the ecology and social dynamics of the Jamaican lizard Anolis lineatopus. This study reported detailed observations of many aspects of behavior, including detailed descriptions of the signaling displays used during intra- and interspecific interactions (A. S. Rand, 1967, “ Ecology and Social Organization in the Iguanid Lizard Anolis lineatopus,” Proceedings of the United States National Museum 122:1– 79). It was this familiarity with what animals actually do in nature—when and where they do it, interacting in which ways with what other individuals—that formed the basis of the theoretical constructs put forth in Rand and Williams’ s article. At its core, Rand and Williams (1970) is an elegant illustration of the art of being a naturalist, demonstrating how an intimate knowledge of the organism can serve as the building blocks for the formulation of new conceptual approaches (see H. W. Greene, 2005, “ Organisms in Nature as a Central Focus for Biology,” Trends in Ecology and Evolution 20:23– 27, and references therein).”

You’ll have to read the essay to get the full details, but here’s the conclusion:

“By detailed field study of the morphology and behavior of sympatric lizards, Rand and Williams (1970) were able to outline the applicability of information theory to lizard signaling behavior and species recognition two decades before those ideas became widely accepted. Moreover, they proposed important hypotheses yet to be investigated. This article demonstrates the key role that natural history plays, and will continue to play, in the conceptual development of animal behavior, evolutionary biology, and many other fields. Although the tools available for technological advancement in these fields are unparalleled, Rand and Williams’ s work demonstrates that observing animals in the wild and developing an intimate knowledge of their ecology serves as the raw material for the development of new and exciting areas of research. Thus, as we move into new frontiers, the appreciation of natural history must be an integral component of our approach and should be encouraged to a new generation of behavioral and evolutionary ecologists.”