Non-alphabetically arranged, the ABC islands lie in a row 20-50 miles north of Venezuela with Curaçao sitting in between Aruba 50 miles to the west and Bonaire 30 to the east. Like many small Caribbean islands, each of the islands harbors but a single species of anole. Previous posts have discussed the inhabitant of Aruba and Curaçao, Anolis lineatus. Bonaire’s anole, however, is a beast of an entirely different stripe.

Anolis bonairensis. Photo by Jonathan Losos

What is curious is not the fact that a small island, not too far from other islands, has its own endemic species. Such anole species occur routinely in the Caribbean, such as A. lividus on Montserrat, A. nubilus on redonda, and A. sabanus on Saba. Rather, the oddity of A. bonairensis is its evolutionary heritage. Unlike A. lineatus, sensibly related to anoles of neighboring northern South America, Bonaire’s pride and joy is phylogenetically closest to A. luciae from distant St. Lucia, fully 500 miles away (check out map above). Given that A. luciae is a member of the roquet clade distributed ubiquitously throughout the southern Lesser Antilles, we must assume that the direction of colonization was from St. Lucia to Bonaire. But how could that have happened? Why didn’t A. lineatus get there first? Or some other anole from a more geographically proximate part of the Lesser Antilles? This discrepancy perhaps can be explained by the geological antiquity of Bonaire and the fact that it is on a different continental plate than the Lesser Antilles; as a result, Bonaire and St. Lucia may have been in much closer proximity in the distant past, facilitating a saurian hop between the two.

Phylogenetic affinities, however, are not the only difference between A. bonairensis and A. lineatus.  I have previously noted that A. lineatus is unusual for a solitary anole (i.e., a species which is the only anole on an island) in that it is very similar, both morphologically and ecologically, to Greater Antillean trunk-ground anoles, whereas most solitary anoles in the Lesser Antilles are trunk-crown anoles. In this regard, A. bonairensis is quite normal: it looks and acts just like a trunk-crown anole, exhibiting relatively short legs and being found regularly up in the trees.

In the cactus patch. Photo by Jonathan Losos

One might postulate that this discrepancy reflects environmental differences among the islands. Truth be told, Bonaire is a cactus-patch of an island, very xeric and for all the world looking like southern Arizona. But Aruba and Curaçao aren’t that different. Moreover, if anything, one might expect more desert-like settings to work against the evolution of arboreality, rather than promoting it.

No, I think the answer lies in evolutionary heritage. Anolis luciae, very likely the Bonaire anole’s ancestor, is also a trunk-crown anole, whereas A. lineatus hails from a clade of anoles as terrestrial as any in existence. I would put my money that the differences between the two species primarily reflect their evolutionary starting point rather than their present-day environs.

That leads to a subsidiary question: if the environments are reasonably similar, why haven’t they converged? The bonairistas have apparently been there long enough that lack of time isn’t a viable answer and, in any case, evidence from the Lesser Antilles suggests that being a trunk-crown anole is the norm. So the focus reverts to A. lineatus. Has it not been in existence long enough to evolve to become a trunk-crown anole? Or are circumstances on Aruba and Curaçao different enough to favor trunk-ground instead of trunk-crown anoles? Or another possibility: maybe either anole lifestyle works, two adaptive peaks (if you will), and species simply evolve to the nearest peak, depending on their starting condition. Plenty of fodder for a research project, if you can just figure out how to test these questions.

But as my mind reels, another thought pops up. If A. bonairensis is old and A. lineatus is young, then why didn’t the Bonaire boys colonize Curaçao and then Aruba? Maybe the ocean currents are the wrong way (I think that’s correct). Or some other species, no longer extant, was there? Or A. bonairensis was there, but then evicted when A. lineatus arrived? Now we’re really getting in to the realm of the difficult-to-test speculation.

But one observation is pertinent: even though the two species are ecologically and morphologically different—similar to two different ecomorphs—they have not been able to colonize each other’s islands, even though trunk-ground and trunk-crown anoles coexist merrily in the Greater Antilles, even on islands much, much smaller than the likes of the ABCs. Yet another mystery to be plumbed.

Young knight anole. Photo from http://www.repticzone.com/forums/Anoles/messages/2236899.html

There’s not a lot in the literature on the size of hatchling anoles, especially the giants, and such toddlers are not well-represented in museum collections. The photos here, easily gleaned from the web, indicate that newborn knight anoles are substantially larger than hatchlings of smaller species. What about other anoles? Does anyone out there know how the size of hatchlings of other large anole species? And how big are the eggs? Pictures, anyone?

Fresh out of the egg. Photo from http://media.photobucket.com/image/recent/RandeMchance/Anolisequestris1dayold.jpg

Several days ago, I challenged Anole Annals readers to identify the three problems with this stamp, issued by Grenada and other nearby islands in their “Reptiles of the Caribbean” series… The answers were creative and insightful, and identified some issues that I had missed. And readers even picked up on one problem I thought would elude them. So what are the problems to which I referred?

The photograph is of a male Anolis grahami.

Problem #1: A. grahami is from Jamaica. Why is it on a stamp from Grenada? This was the gimme.

Problem #2: This individual actually was from Bermuda, where A. grahami was introduced in 1905. Bermuda, of course, is not in the Caribbean. This was the tough one that no one realized.

Problem #3: This is my photograph, used without my permission! Don’t believe me? Here’s the unabridged version, which appears on Todd Jackman’s Anolis webpage, which Todd speculates, probably correctly, is where the Grenadians got it:

I can assure you that I never granted permission for its use, and until I stumbled across it on the internet, I was unaware that it had been planted on a $6 stamp (royalties—ka-ching!). Does anyone know a good intellectual property rights lawyer with offices in the Lesser Antilles?

It turns out, however, that kerfuffles with anoles and postage stamps are not unheard of. Here’s another, brought to my attention by Uwe Bartelt, rumored to be the world’s leading anole philatelist.

First, congratulations to Ramon E. Martínez-Grimaldo for his overwhelming electoral majority in the Anole Photo Contest. His prize will soon be winging its way southward.

Second, the good people at zazzle.com have permitted us to drop the price of the 2012 Anole Calendar by 30%. Get ‘em while supplies last! Go to http://www.zazzle.com/anoles_2012_calendar-158860158425229228 and use the coupon code ALLCALENDARS.

How are these two points related, you might wonder? The answer is easy. We will be having a contest for photos to include in the 2013 Anole Calendar with a nifty prize. So start snapping those pix and fire up Photoshop–the contest will come around before you know it!

Anolis lineatus from Curaçao

Several previous posts have discussed the odd case of Anolis lineatus on Curaçao, whose dewlap differs from one side to the other. Rand and Rand reported this in 1967, but the observation was pretty much forgotten until earlier this year, when Matt Brandley and compatriots confirmed the Rands’ claim. Shortly thereafter, Melissa Losos and I travelled to Curaçao as well and observed the same phenomenon, allaying concerns that the Brandley team was covering for the Rands.

But since these posts, many AA readers have no doubt been sleepless at night, pondering the obvious question: what about A. lineatus on Aruba? Do they, too, have mismatched throat fans? Indeed, one could imagine a scenario in which they might not. Asymmetry is a common result of low levels of genetic variation (although there is a lot of quibbling about this in the literature). Curaçao is downstream in an ocean current sense from Aruba. Thus, it could be that the Curaçao population of A. lineatus was founded by one or few Arubians, and thus the resulting founder effect gave rise to the dewlap discordance.

An exciting hypothesis that I am pleased to immediately quash: Anolis lineatus on Aruba have asymmetric dewlaps just as their brethren on Curaçao, and the asymmetry arises just as Brandley reported.

Two-faced anole of Aruba. Photos courtesy of Alexis Harrison.

On one side of the dewlap, and one side only, along the outer margin, there are many large white scales, giving the dewlap a yellowish appearance when viewed from a distance, whereas on the other side, a paucity of scales lets the orange shine through unfettered. This asymmetry appears to occur in both males and females and shows no obvious directionality, the white scales occurring on the left side in some lizards and the right in others.

Now for more matters Arubian: as far as I can tell, there is basically nothing in the literature on the natural history of A. lineatus on Aruba. Field guides suggest that the populations are extremely similar, with perhaps slight color and patterning differences, and I can attest that that this is so. The Aruban lizards, however, seemed substantially larger—males to 83 svl on Aruba versus 76 on Curaçao—but this is based on a geographically limited sample on both islands.

Ecologically, A. lineatus on Aruba are like their counterparts. The more I saw them, the more I was convinced they are good trunk-ground anoles: muscular lizards, with long hindlegs, even a bit of a tail crest, like some A. sagrei (not as grand as the Puerto Rican crested anoles). Ecologically, they were very common on large tree trunks and rocks, usually a meter off the ground at most, though occasionally a bit higher. Only a few were seen up in the trees. In addition, in some places on both islands, they are extremely common, just as trunk-ground anoles often are.

The trunk-ground nature of A. lineatus is unexpected, as in the Lesser Antilles, solitary anoles (i.e., anoles living on an island with no other anole species) are almost almost very similar to trunk-crown anoles, both in terms of morphology and habitat. Why this species on these two islands bucks this trend would make a good study. One possibility is that A. lineatus is derived from the chrysopelis clade, which contains species all of which are more or less terrestrial. Another possibility has to do with the extremely arid—downright desert-like in places—climate on these islands.

One last note: for all you anole neophytes. Anolis lineatus is about the easiest anole to noose that ever existed. They sit right out in the open, on big, unobstructed perches, and hardly move as a noose is lowered over their head. A great starter anole, and you can celebrate by hitting the casinos in Aruba or sipping a Blue Lagoon, made from the eponymous curaçao liquer.

For reasons I can’t recall, I stumbled across this stamp on the internet. There are three things wrong with this. What are they? Ok, one of them is more an oddity than a problem, and that’s a pretty easy one. But I bet no one can come up with either of the other two.

A common challenge I often face is finding best way to ship small anoles, often hatchlings or juveniles, to collaborating labs. While hatchlings are often hardier than they look, they do require some extra protection from getting bumped around so I don’t like using bags. Most Tupperware containers are simply too big and can, at times, be difficult to get the small lizards in and out of. The  package I received today used an ingenious method of packing small lizards in recycled plastic water bottles. Each bottle was loosely packed with paper towels with one or two lizards added. The bottles have a relatively small foot print and little space between bottles when packed tight. Each bottle cap had two small holes drilled for air exchange. Removing the lizards was surprisingly easy. I simply pulled each paper towel out using forceps and gently tapped each bottle until the lizard slid out the hole, usually in two to three taps. While working with these bottles today I could not help but to also think that I was on the verge of the next great Sobe ad!

Anolis insignis above, Anolis transversalis below. Males on left, females on right.

Sexual dimorphism–differences between the sexes–have been greatly studied in anoles, and so has dewlap color and patterning. But little research has been directed to the phenomenon of sexual differences in dewlap color or pattern. Such differences are relatively rare in Caribbean islands, but much more common in mainland species. Why does this occur? Nobody knows. In fact, what female anoles use their dewlaps for has been little studied (another phenomenon, fodder for a future post, is differences in the size of the dewlap between the sexes, which can be quite substantial).

In any case, here’s a sampling of dimorphic dewlaps.

Anolis fitchi (female and male), and Anolis orcesi (female and male)

Photos courtesy Melissa Woolley.

Anolis lyra, female on left (photos courtesy Fernando Ayala).

Photos courtesy of Fernando Ayala

Anolis fowleri, as documented by Dan Scantlebury here.

And a recent post has just discussed this phenomenon in Venezuelan anoles, such as this one.

Anolis tigrinus, male on left, female on right. From Ugueto et al., Carib. J. Sci., 2009.

A friend of mine was in Las Tablas, Puntarenas, Costa Rica, ~1850m and found these guys. They were sleeping on some overhanging roots where the ground had broken off near a cattle pasture. We were wondering about which species they belong to and thought the brilliant people here could help. Thanks!

A view of the volcano as seen from the abandoned town of Richmond Hill. Photo: Jim Hewlett

As “anolologists” we think of the Lesser Antilles as one of the major treasure troves of colorful and extravagant lizards. They have been the subject of many AA posts (here, here, here, and here, among others). While gazing at anoles dewlapping in swaying palm trees, it’s easy to forget that the Lesser Antilles are a volcanic arc. However, on the tiny island of Montserrat where Anolis lividus is found, the volcano is alive and active. After a long dormancy the volcano awoke in 1995 and, within only a few weeks of activity, the capital city of Plymouth and surrounding areas were carpeted in several meters of pyroclastic material. Today Plymouth is a modern-day Pompeii. Plymouth is also the type locality for Anolis lividus, a charismatic medium-sized lizard from the bimaculatus clade of Lesser Antillean anoles. It was extraordinarily abundant in Plymouth and surrounding areas, according to Skip Lazell’s 1972 monograph in the Bulletin of the Museum of Comparative Zoology. Since 2009 I’ve been surveying this lizard across the island, and have tried to find it as close to the volcano as I can get.

A picture by the Montserrat Volcano Observatory showing the impact of volcanic dome collapse along the Belham River Valley in January 2010.

Figure 1. Map of Montserrat. Some of the localities where I have sampled A. lividus are shown with black dots. Sites where A. lividus was sampled before the eruption are shown with stars. The exclusion zone boundary is shown with a solid line. The volcano is shown with a triangle.

The permanent exclusion zone is a fenced off region south of the Belham River Valley (Figure 1). The Belham is a barren bed of ash and sand that gets periodically assaulted by pyroclastic flows. It effectively separates the habitable part of Montserrat north of the riverbed from the dangerous part of the island to the south. Getting into the exclusion zone is no easy task. While the volcano is active, access is tightly regulated. Even in the best of times, getting into Plymouth is impossible and so we can only survey in the ruins of towns outside of Plymouth, such as Richmond Hill and Fox’s Bay. In summer of 2009 I went into the exclusion zone with a surveying team of geologists. I was allowed to accompany the team, but had to go where they went, and could not stray far from the vehicle. I was able to find 2 lizards on that trip, a mating pair in a tree just outside of Richmond Hill. Since then I made a brief jaunt in January 2011 with the chief of police and couldn’t find any lizards. Both trips were frustratingly brief. With the geologists I could only look in the immediate vicinity of where they stopped, and couldn’t survey the trees and vegetation along the road. In January 2010 I only had 45 minutes to survey a single part of Richmond Hill. After the dome collapsed in 2010, the volcano has been surprisingly quiet. As a result, much of the exclusion zone is open to the public during the day. This time, I was able to take my time, go where I preferred, and I brought reinforcements.

We searched high and low, in and out, and all around for Anolis lividus.

Along with Jim Hewlett, a Professor at Finger Lakes Community College, his three students, and Troy, who can only be described as an “opinionated” ex-pat, we traveled into the exclusion zone for a few hours of herping. We visited all my old sites from 2009 except for St. George’s Hill, which is still off limits. We visited new sites at Fox’s Bay and in Richmond Hill. We searched outside and inside abandoned homes. We drove at a snail’s pace between sites in two cars so that we could all scan the bushes, trees, and fence posts for lizards. I kept my noose in my lap, certain that I would find Anolis lividus everywhere. I mean, the volcano has been quiet for almost two years, anoles can disperse pretty quickly, and the habitat looked better than I had ever seen it – barely any ash, no rancid sulfur smell in the air. They should be here. Right?

The Belham River Valley, which separates the inhabited region in the north from the exclusion zone in the south.

I can report that they are nowhere to be found! A team of six working to find the slightest glimmer of green scales in the sun came up dry. It was a frustrating endeavor, I can assure you. It was also frustrating leaving the exclusion zone, as we were locked in by the police department. A policeman keeps a log of visitors to the exclusion zone. Apparently we tried to leave during the shift change. It is possible that the Belham River Valley prevents dispersal from the north, which abounds in A. lividus, to the southern region even if the conditions permit habitation. It is a wide, barren ashbed with little vegetation that gets periodically assaulted by pyroclastic flows and lahars, or landslides of ash and volcanic material.

As we tried to leave the exclusion zone, we discovered that we were locked in... for much longer than ten minutes.

The ex-pat Troy told me that there are anoles in Isle’s Bay, which is on the volcano’s side of the Belham, but outside of the permanent exclusion zone. After the volcanic dome collapse of 2010 conditions have been quiet enough to permit Isle’s Bay, a small residential community with nice villas, to reopen. While it is not in the permanent exclusion zone, it is in Zone B, which gets periodically evacuated when activity rises.

Anolis lividus. Northeastern Montserrat. Photo: Jim Hewlett

It would be intriguing if A. lividus is in Isle’s Bay but not in the permanent exclusion zone. The habitat in Richmond Hill and Fox’s Bay appears quite suitable, and it is not very different from sites in the north where A. lividus is found, except for a bit more acid rain damage. Are humans mediating recolonization south of the Belham to the community of villas in Isle’s Bay? Given enough time, will they colonize other parts of the exclusion zone? It’s only a rumor, and I was unable to visit Isle’s Bay on this trip to check if they are present, but it is an intriguing possibility. To all you anolologists visiting Montserrat – I encourage you to find out! In the meanwhile, here are some photos of Anolis lividus that we saw in the northern half of the island during this trip. There, they are still abundant and charismatic, making this trip as exciting as ever.

Anolis lividus. Northeastern Montserrat. Photo: Jim Hewlett

Anolis lividus. Northeastern Montserrat. Photo: Jim Hewlett

Anolis lividus. Northeastern Montserrat. Photo: Jim Hewlett