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Creationists on Lizard Evolution Study: “What’s the Big Deal?”

discovery institute

Last week, Yoel Stuart and colleagues (including me) published a paper demonstrating that green anoles had rapidly (ca. 20 years) evolved an increase in toepad size as a result of upward shifts in habitat use caused the presence of brown anoles.

The Discovery Institute, an organization devoted to the advocacy of creationist views, posted a blog yesterday saying, basically, “this is not news?” After summarizing the study, here’s what they have to say:

“….these scientists found that when a new species of lizards invaded another’s territory (in fact the new species was placed there intentionally by the researchers, meaning they weren’t quite studying “natural” selection), the old one sought higher ground. That seems like a smart thing to do. To go along with the new territory, they subsequently evolved “larger toepads (see here for a picture).

After reading this, what I really wanted to see was the precise sizes of the toepad and compare the changes. But alas that information is not in the paper. I tried downloading the supplemental materials but it’s not there either. So let’s assume that the toepad size changed a lot. What have we shown?

Not much. We’ve seen that the size of lizard feet can change in response to invaders’ driving a species to perch at higher levels in the trees. No new traits arose. Only the size of a pre-existing trait changed. Again, that’s interesting but such changes in the size of lizard feet do very little to explain the origin of lizards in the first place, even if these changes happen in just a few generations.

If we take seriously the statement from the authors that the modest results from this study can help test “evolutionary hypotheses about phenomena … on time scales too long for direct observation,” then that implies that over long periods you might be able to change the size of an organism or some of its body parts. Since when is that news?”

The Blue-Dewlapped Anole of Grand Cayman

 

conspersus displayingNot many anoles have blue dewlaps, so we were delighted to see Ann Stafford’s tweet of this lovely  conspersus from Grand Cayman strutting its stuff.

Where Do Anoles Lay Their Eggs?

Anole eggs found in a tomato pot. Photo by Karen Cusick.

The egg-laying habits of anoles are surprisingly little known. On Daffodil’s Photo Blog, Karen Cusick recently reported on the discovery of eight–count ’em, eight!–anole eggs in a tomato plant pot. Readers, where else have you found anole eggs?

Also, whose eggs are these? Both green and brown’s occur in Karen’s backyard. In Anolis Newsletter V, Todd Vincent provided tips on how to tell them apart.

Brown and green anole eggs. Photo by Todd Vincent.

Brown and green anole eggs. Photo by Todd Vincent.

And for some delightful footage on baby anoles, let’s not forget this old post.

Anoles Moving North, Way North

A recent paper by Matt Helmus, Luke Mahler, and Jonathan Losos highlighted the ways in which globalization has influenced the distribution of Caribbean Anolis lizards. At the heart of this research was the relationship between commercial shipping traffic and lizard biogeography. Two more recent observations can now extend these findings well beyond the Caribbean, much, much farther north.

First, Twitter user  recently posted a story about a stow away green anole that he found on pallet in Edmonton, Canada. This was a shipment of oil field supplies that originated in Houston, TX and that took ten days to reach its destination. This male green anole survived the trip all the way to Canada and is now housed in a new terrarium. The tweet originally posted October 16th and since then the anole has shed and appears to have adapted well to its new home.

An anole in the great white north.

The Canadien green anole.

Photo by Randi Duun

In separate case of stowaway lizards, another anole survived a transatlantic journey to Denmark in a shipment of bananas and was discovered incapacitated on the floor of the stockroom where incoming bananas are fumigated. The photo is too small for me to be certain, but this appears to be an Anolis cybotes female. According to the original post by Randi Duun in the “Anoles” Facebook group, the shipment originated in Colombia, Costa Rica, or the Dominican Republic so this would be consistent with an A. cybotes hitchhiker. It would be interesting to know how long a shipment like this takes, but I bet that it is longer than ten days port-to-port. Regardless, just like the globetrotting green anole, this anole is healthy following its journey, housed in a terrarium and enjoying Danish mealworms.

In contrast to the research described by Helmus et al, it is probably safe to assume that despite the perseverance of these anoles, and any others that make their way towards the arctic circle in subsequent shipments, escapees will not be establishing viable introduced populations.

 

New Phylogeny for Amazonian Dactyloa Anoles: Multiple Evolution of Horns, Dewlap Color Evolution, New Divergence Time Estimates

Anolis phyllorhinus. Photo by Bret Whitney

Anolis phyllorhinus. Photo by Bret Whitney

Anolis dissimilis. Photo by Paulo Melo Sampaio

Anolis dissimilis. Photo by Paulo Melo Sampaio

In a fascinating new paper, Ivan Prates and colleagues report on a phylogenetic analysis of Amazonian Dactyloa clade anoles with implications for a number of important topics in anole evolution.

The authors generated new mitochondrial and nuclear gene data for many Amazonian Dactyloa and combined those data with existing data from previous studies. Of particular note was inclusion of Anolis dissimilis, until recently known from only a single locality, and the Amazonian horned anole, Anolis phyllorhinus.

The paper had four main results, which I’ll go through seriatim. First, the overall phylogeny is very much in accord with Castañeda and de Queiroz’s previous work. The biggest difference is that A. dissimilis occurs in a distinct clade with A. neblinus and A. calimae. A relationship between the latter two species had been suggested by the previous work; A. dissimilis had not been included in those studies. The three species have quite disjunct geographic distributions (Amazonia, western Colombia, and the tepuis of the Guiana Shield, so finding them to comprise a distinct clade is interesting.

phylogeny dissimilis

Anolis punctatus. You can almost see a horn ready to burst forth from the tip of that snout. Photo by Arthur Georges.

Second, as the figure below illustrates, A. phyllorhinus, as expected, groups with A. punctatus, whereas A. proboscis groups with the phenacosaurs (heterodermus group; though A. proboscis is not actually included in the analysis because genetic samples were not available; however, recent studies clearly indicate that A. proboscis belongs with this clade). Prates et al. note that, other than the horn, A. phyllorhinus and A. punctatus are morphologically very similar. I’ll take that one step further–you can almost imagine the antecedents of the horn as a swelling on the tip of the snout of A. punctatus. And, in addition, note that the horns of the two-horned species are very different-looking. Although Williams placed them in the species group, he did note that they actually didn’t look at that much alike. We now know that he was correct in this observation–hornedness is a convergent trait in anoles (no, I’m not calling it horniness).

horns

Third, Prates et al. calculated divergence times, calibrated with three fossils that can be confidently placed in iguanian phylogeny.

Find the Anole: Squamates Versus Archosaurs

Regular readers of Anole Annals may remember the “Find the Anole” series that has been popular over the last few years. It has been a while since we enjoyed such fun times, so I wanted to breathe new life into this classic challenge.

Earlier today I visited Dinosaur World in Plant City, Fl. and enjoyed the contrast between Mesozoic and Cenozoic  reptile diversity. It was very exciting. Below are two images from their grounds for your enjoyment. Can you find and identify the anoles in these photos? A far bigger challenge may be to identify the dinosaurs illustrated by these statues.

Find the anole 1

Find and identify the anole.

On a separate note, if you are ever passing through central Florida with your families, stop by Dinosaur World. The interpreters were quite good with our kids, there are over 200 life-sized (and colorful) dinosaur statues, they clearly state that the earth is 4.5 billion years old, and there are no humans riding dinosaurs. I was pleasantly surprised by all of this in this part of the country. Its worth a few hours of your time!

Find the anole and identify the species.

Anoles and Hummingbirds

Posted by Lorie on Birds and Blooms.

Survey: How Many Lamellae Are on This Toepad?

Hi everyone, I apologise for the repeat post. As mentioned by Martha, it may not have been obvious from the initial post that there was a survey inside!

So, please forgive me while I repost with an amended title in the hope of getting a few more poll participants. We are only just into double figures (including only 3 of you who have previously published on the subject) – surely we can do better than that! Thank you to everyone that has already contributed. I will present the results in a follow up post in week or so depending on participant activity.

****

One of the age old questions in anole morphology is at what point do you stop counting lamellae on the toepad?

Without giving any more information on various techniques or methods, I thought it would be interesting to ask the AA community their personal opinions. Below I have attached a flatbed scan of a toepad. Could people please fill out the corresponding poll below, and I will present the results in a follow up post!

alt text

Lamellae numbered 1-51 on the 4th digit of an Anolis lizard hindfoot

Six New Mexican Anoles Described

nietoi

Gunther Kōhler and colleagues have just published in Zootaxa a new revision of some Mexican anoles, including the description of six new species and the sinking of one species. Rather than describing the work, I think it would be more effective to present the title and abstract:

A revision of the Mexican Anolis (Reptilia, Squamata, Dactyloidae) from the Pacific versant west of the Isthmus de Tehuantepec in the states of Oaxaca, Guerrero, and Puebla, with the description of six new species

GUNTHER KÖHLER1, RAÚL GÓMEZ TREJO PÉREZ, CLAUS BO P. PETERSEN & FAUSTO R. MÉNDEZ DE LA CRUZ

We revise the species of anoles occurring along the Pacific versant of Mexico west of the Isthmus de Tehuantepec in the states of Oaxaca, Guerrero, and Puebla. Based on our analyses of morphological and molecular genetic data, we recognize 21 species, six of which we describe as new (i.e., Anolis carlliebi sp. nov., A. immaculogularis sp. nov., A. nietoi sp. nov., A. sacamecatensis sp. nov., A. stevepoei sp. nov., and A. zapotecorum sp. nov.). Furthermore, we synonymize Anolis forbesi Smith & Van Gelder 1955 with Anolis microlepidotus Davis 1954. Of the recognized species, six have smooth ventral scales (i.e., Anolis dunni, A. gadovii, A. liogaster, A. omiltemanus, A. peucephilus, and A. taylori) and 14 have keeled ventral scales (i.e., A. boulengerianus, A. carlliebi, A. immaculogularis, A. megapholidotus, A. microlepidotus, A. nebuloides, A. nebulosus, A. nietoi, A. quercorum, A. sacamecatensis, A. stevepoei, A. subocularis, A. unilobatus, and A. zapotecorum). In one species, A. macrinii, the ventral scales vary from smooth to weakly keeled. For each species we provide color descriptions in life, color photographs in life, descriptions and illustration of hemipenis morphology (if available), descrip-tion of external morphology, distribution maps based on the specimens examined, comments on the conservation status, and natural history notes. Finally, we provide a dichotomous key for the identification of the 21 species of anoles occurring along the Pacific versant of Mexico west of the Isthmus de Tehuantepec in the states of Oaxaca, Guerrero, and Puebla.

Florida Festival Features Green Anole

Karen Cusick, author of  Lizards on the Fence and tender of Daffodil’s Photo Blog, writes:

You may remember that the Wild Amelia Nature Festival (Amelia Island, FL–just north of where I live) chose the green anole as their Critter of the Year for 2015. I was looking at the Wild Amelia website and they are already starting to gear up for the festival, which will be held May 15-17. They’ve designed a new website logo featuring a green anole, and there are going to be tee shirts with the logo. The website button to buy a tee shirt doesn’t work yet, but that should be fixed as the festival gets closer. I’m going to check on that.

There’s only a small size image of the logo so far, but I’m attaching it anyway. It looks like it’ll be a nice shirt.

They’ve scheduled a series of nature-based seminars in the months leading up to the festival, and the last one is May 12, when the director of the Jacksonville Zoo, Tony Vecchio, will give a presentation about the green anole and the Zoo.

I’ll let you know if I hear any more anole-related news about the festival!

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