Category: All Posts Page 129 of 149

Anolis maynardi. Photo by J. Losos

AA commentator and Jamaican student Kuti Ra remarks (links to previous posts added by me:

“I notice a lot of fuss on Anole Annals about the skull morphology of carolinensis clade anoles, so I thought I’d weigh in with a theory of my own. All that you are about to read comes from pure indirect observation and speculation, so please keep that in mind.

First of all, I believe that the skull morphology of these anoles is directly related to their arboreal lifestyle and, more specifically, to the diet that such a lifestyle would facilitate. There have been several posts [1,2] about nectivory in anoles, but all these instances seem to involve carolinensis clade anoles (A. maynardi and A. carolinensis) and possessing a long tapered skull would undoubtedly make such feeding behaviour easier; this could come very useful as a trunk crown anole would encounter several blossoms and such high up in the trees in addition to various small fruits. In this respect, the forceps-like jaws could function something akin to a fruit-eating birds’ bill; considering all this, it would seem that the jaw morphology of carolinensis clade anoles is simply a useful adaptation for life in the canopy. This conclusion seems even more likely when you consider that sexual selection very likely wouldn’t play a role here as observations of Anolis maynardi suggests that longer-snouted males aren’t any more successful at securing mates; and why would they be, having such a long jaw narrow jaw would translate to a lower bite force and thus a less likely chance of emerging as the victor in a territorial battle?

No long schnoz here. Anolis grahami. Photo by J. Losos

Of course, this theory begs the question ‘‘Why didn’t the trunk-crown anoles on other Greater Antillean islands evolve to look like their carolinensis clade counterparts?” In my opinion, the answer is that they didn’t need to. You see, on Jamaica the trunk crown anole, Anolis grahami, has a skull that is overall very similar to the sympatric A. lineatopus, and though they are traditionally classified as belonging to different ecomorphs, I can testify from personal observation that they often share the same micro-habitat and thus compete for the same resources; however since there are only a few ecomorphs present  on Jamaica and wherever these two species occur they are of the only common species in that area, the resources available in a particular micro-habitat are often sufficient to support full populations of the two species; thus neither species has reached the point where it needs to adapt to consume different things than the other. Moving on to the neighbouring islands of Hispaniola and Puerto Rico, one can recognize three things: first off, there are a greater number of trunk-ground anoles than on Jamaica, and more trunk-ground anoles than trunk-crown; second, all or almost all of the other ecomorphs are present  and third the jaws of the trunk-crown anoles are noticeably longer than that of sympatric trunk ground species (more so on Hispaniola than on Puerto Rico). On these islands, where there are often more species of anole competing for the resources of the trunk-ground niche, as well as additional ecomorphs to occupy other microhabitats, trunk crown anoles are becoming more and more specialized to take advantage of the resources available to them in the trees.

On Cuba, the largest island, there are often a great number of sympatric species of all ecomorphs and thus the habitat use of the anoles there is the most deeply segregated. I have read that in the Cuban rainforest, Anolis porcatus is almost never found out of the canopy; this seems to also be true of A.allisoni. This greater restriction to a particular microhabitat and need to capitalize on the resources found there  is what I believe  caused the Cuban trunk-crown to evolve such drastic adaptations to a trunk crown lifestyle. Well that’s my theory in a nutshell. I don’t know if all this has been said before but I haven’t been seen it mentioned. Like I said, most of it is based on indirect observation (looking at pictures on Google images) and speculation so I f you see any problems or holes in the theory, or if you’d like me to elaborate on or better explain a particular point, please let me know.

I think it is also important to note that the heads of trunk-crown anoles start out short on Jamaica and steadily get longer until you get to Cuba.

All the scenarios above would apply only to anoles in their natural habitats and not to populations inhabiting urban areas where more resources are available.

On a side note, have you ever noticed that trunk crown anoles have relatively tiny dewlaps? Perhaps one should look into how the ecomorph dewlaps are affected by those of neighboring ecomorphs. For example no matter what island you go to, the dewlap of any trunk-ground anole will always be comparatively larger than the dewlap of any trunk-crown anole on that island. I haven’t seen all species for Cuba, but I’m still pretty confident about it. I think these two ecomorphs in particular may have some very big effects on each other  that no one has noticed yet.

Ever wondered what the most viewed post on Anole Annals is? I bet it keeps many of you up late at night trying to guess. So, I’ll tell you. Over the last year, the single most viewed page is the one entitled “The Proper Pronunciation of ‘Anole’.” In that post, an AA reader asked how to pronounce our favorite noun, and many readers responded.

But that was more than two years ago, and languages evolve swiftly. Moreover, many have joined  AA’s readership since then. So, I’ll throw out the question again. For what it’s worth, here are my thoughts, as expressed Lizards in an Evolutionary Tree (p.10):

“…honorable, right-thinking people can disagree over whether the correct pronunciation is uh-nole or an-ole. I am less charitably inclined to my ninth grade biology teacher’s uh-no-lee, but, although I have never heard “anole” articulated in that way by anyone else, I am told that it is common in the South, from whence she came (I was surprised to find that this is the preferred pronunciation of the Random House Unabridged Dictionary, according to www.dictionary.com).

As for the origin of the name, Daudin [1802], who named the genus, said that “anolis” was the name the indigenous Caribs used for these lizards. However, there is some possibility that in fact “anolis” may have been their name for lizards in the genus Ameiva and that the correct Carib word was “oulléouma” (see discussion in Breuil, 2002). Right or wrong, Daudin clearly chose the more mellifluous name to bestow upon these lizards! A more interesting, though doubtless less accurate, explanation is the Saba Tourist Bureau’s statement (www.sabatourism.com) that “The scientific name of ‘Anolis’ comes from the popular name of “anole” for these lizards. Anole is an ancient African name, meaning “little devil”, that is given to small lizards in western Africa.”

Dear readers of Anole Annals,

Last year, I posted here requesting photos of extended dewlaps of adult male anoles of any species, for use in a study of the relationship between dewlap size and speciation rate. I thank all the readers who sent in one or a few photos, as well as the prolific photographers who have contributed many more. I even chipped in a few of my own photos last summer in Puerto Rico:

Thanks to everyone’s contributions, I’m up to around 185 species, even better than I’d hoped for. Before I start the analyses, I wanted to put out another call for photos, to see if anyone who missed the first post can help to fill in some of the species that are still missing from the collection.

Read More

No, it’s not a hybrid, but why do some anoles do this? And how? Read all about it in a recent post on dust tracks on the web.

Photo by Luke Mahler.

I have noticed things like this myself. Some times when you noose a lizard, the scales underneath the noose turn dark. And so species show patterns when they are stressed that they don’t normally flaunt, like the A. garmani below. Anyone have thoughts or similar observations? Or a better photo of the phenomenon in garmani? Some images online suggest that males do this to a lesser extent when being aggressive to other males.

I was communicating recently with an eminent Gondwanan herpetologist, one who has published far and wide on many issues pertaining to many species. I remarked that it was time that he/she reached the pinnacle and worked on anoles. I received this response:

“To my mind, an anole is a little like a bicycle with training wheels – quite useful for youngsters to practice on and develop their skills. But just a pale shadow of the subtlety and sophistication of real lizards.  They just make it too easy to get lots of papers in good journals, and discover neat things.  Where’s the challenge?”

In contrast to their ubiquity at the evolution meetings [1,2], anoles are barely in attendance at the enormous Ecological Society of America meetings. Last year there were but three (including the famous “Kitty Cam” talk), and this year the dearth is worse, with but a single talk this week in Minneapolis. So, here it is, by Rich Glor and part of the symposium on “Coexistence of Closest Relatives: Synthesis of Ecological and Evolutionary Perspectives”:

Patterns of Anolis lizard coexistence across a complex island landscape

Thursday, August 8, 2013: 3:40 PM

M100EF, Minneapolis Convention Center

Richard E. Glor , Biology, University of Rochester, Rochester, NY

Background/Question/Methods

In species rich adaptive radiations, complex patterns of species coexistence result from speciation and natural selection acting over evolutionary time. In Anolis lizards, similar communities of 4-6 arboreal microhabitat specialists that partition available perches by size and height have evolved independently on each of the four largest Caribbean islands. These well-studied communities of anole ‘ecomorphs,’ however, account for only a fraction of anole species diversity. Most anole diversification has occurred subsequent to microhabitat specialization, resulting in complexes of closely-related species that belong to the same ecomorph but appear to be allopatrically or parapatrically distributed in different macrohabitats. We use integrative analyses that combine thousands of anole species occurrence records from public biodiversity databases, GIS environmental data, molecular phylogenetic and population genetic data, and data on phenotypic variation to test three predictions about anole species co-occurrence across the island of Hispaniola: (1) local communities tend to be comprised of microhabitat specialists that evolve relatively early in anole radiations, (2) closely-related or incipient species tend to be allopatrically or parapatrically distributed in distinct macrohabitats, and (3) habitat filtering in extreme habitats leads to communities in which species that are more closely related to one another than expected by chance.

Results/Conclusions

Our analyses support the prediction that local communities tend to be comprised of phenotypically distinct microhabitat specialists that evolved early in anole radiations and are relatively distantly related. Our analyses also support the prediction that closely-related species tend to be allopatrically or parapatrically distributed in distinct macrohabitats. This result, together with a growing body of molecular population genetic data, suggests that both geographic and ecological processes play an important role in recent anole speciation events, and dictate patterns of co-occurrence in closely related anole species. Finally, we find preliminary support for the importance of habitat filtering by recovering evidence for a latitudinal gradient in the phylogenetic composition of local communities whereby communities at the highest altitudes tend to include more closely-related species than communities at lower altitudes. This pattern is particularly evident in the Cordillera Central, where communities of closely related and ecologically unusual species tend to occur at the highest altitudes.

Several years ago I reviewed some lighting options for people interested in hunting anoles at night (Who wouldn’t? Throw that noose away!). At the time I recommended several readily available lights ranging from 300 to 700 lumens, $60 to $500 respectively. Needless to say, most anole enthusiasts were likely priced out of the brightest lights. However, I recently found an option affordable to even our dedicated summer field assistants. A relatively new company to the US, Magicshine, advertises an 1100 lumen light for only $90, the MJ-808U.

Maginshine MJ 808U

Now the first thing we should all do is assume that this is too good to be true. In just a few years our discussion has gone from $500 to $90 for a supposedly superior light. Come on! Online reviews of Magicshine’s products are generally favorable, but mixed. Reviews on mountain bike forums comment on the relatively poor construction and historically bad batteries. Several reviewers have also commented on overheating problems for riders not peddling their hardest.The best part of Magicshine is by far their price. But the last I checked we rarely look for anoles on bikes at night so we will need to take all of this in with some hesitation.

So what about herping? Time will ultimately tell how these lights hold up to our uses. I received my light in the mail earlier this week and have used it twice. To keep my hands free I also purchased the accessory head strap for about $8. I also need to purchase the extension cable as the attached cable between the battery and light is too short to reach my backpack from my head. First impressions, the light is retinal burning bright. I have absolutely no complaints there. I will warn you now, however, that the light gets hot, but has yet to overheat for me. I haven’t fully run down the battery yet either, but it has lasted for over 90 minutes of burn time so far. In summary, my first impressions are as the online reviews suggests, there are both pros and cons to this product, but for $90 why not give it a try. I am cautiously optimistic.

Has anyone else discovered this light yet? If so, please share your reviews with the community.

The Cover of Anolis Newsletter III, in which Ernest Williams revealed the POUM

Here at AA, we’ve often discussed Ernest Williams’ Principle of Unsympathetic Magic [1,2], which states that any hypothesis formulated in the field will immediately be disproven by the next observation. Janson Jones has recently uncovered its corollary, the Kakakairos of the Unprepared, which proclaims that whenever one goes into the field without a piece of equipment that one normally has, a situation will arise in which that equipment is needed. Or, more generally, whatever one is unprepaped for will happen. Janson explains it much better at Dust Tracks on the Web. All I can say is, it happens to me all the time.

Years ago I heard reports that Anolis cholocyanus had established a small population in  Dade County. Does anyone know if this population is still viable? I am starting a new project and it would be quite beneficial to examine a few living specimens before investing in a full trip to the Dominican Republic. If anyone has any information about the status of this introduced species I would be extremely grateful to learn more.

Have a good weekend!