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An iguana at the Fairchild Botanical Garden. Photo by Diana Robinson.

AA contributor James Stroud thinks it might. In an informative recent article in the Garden’s magazine, The Tropical Garden (go to page 28), James discusses the species, which range from the glorious red-headed agama to six–count ’em, six!–introduced anoles, along with the native green. Of course, introduces species are not a good thing, but at least they’re quality species! You can also read more about them in a recent AA post by James.

Red-headed agama at Fairchild. Photo by James Stroud.

More spiders eating anoles (for previous aranean saurivory, see this and that). This time it’s a brown anole, A. sagrei (also, this time), falling prey to a ctenid spider in Cuba. This one’s particularly gruesome–the head’s already digested away and eaten! The authors are Elier Fonseca Hernández and Tomás M. Rodríguez-Cabrera and the paper’s just out in the most recent issue of IRCF Reptiles & Amphibians.

As a follow up to my recent posts on lamella scale counts on toepads, I thought I would share a tutorial I created for measuring toepad length and width using the program ImageJ. ImageJ is a free, open-access program that allows you to perform a suite of analyses on pictures or scans. I hope this could be a useful tool for graduate students, as well as research technicians and assistants.

Measuring the width of a Cuban brown anole (Anolis sagrei) toepad using ImageJ

Tutorial: How to measure Anolis toepad length and width using ImageJ

You can download ImageJ from here.

Feel free to use and distribute as you need! If anyone has any comments, or spots any recommendations or improvements that can be made, then please feel free to contact me.

Rather than trying to explain this, I’ll simply post the tweet that alerted me to it.

Everyone knows that geckos are anole wannabees, but here in Asia, there are, sadly, no anoles (except introduced brown anoles in Taiwan and Singapore). So, in their absence, an anolologist is forced to count geckos. Fortunately, in some places, they’re not hard to find. Just how many are there on the ceiling of this building near Khao Sok National Park in Thailand?

I have now compiled the results of the survey I previously posted here on Anole Annals. I asked readers at what point on the image below would they stop counting scales if conducting toepad scale counts?

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

As expected, there was a lot of disagreement! However despite some confusion, scale 32, roughly coinciding with the joining of the second to the third phalanx, was a clear favourite (Fig 2, below) (see Kevin De Quieroz’s comment here regarding some confusion with phalanx numbering).

Fig 2. AA readers choice of where one should stop counting during toepad scale counts.

However, I was most interested in the demography of the surveyors. I have met other graduate students confused about this topic, and relevant guidance material seems limited to anecdotes. Would we then expect there to be most confusion among contributors who have never published scale count data?

Fig 3. Survey data broken down into publication record: a) those that have never published scientific articles which include toepad scale counts (blue), b) those that have published a scientific article including toepad scale count data (red), and c) those which have published but were not responsible for conducting the scale counts (green).

The majority (60%) of votes from published researchers fell among scales 32-33, suggesting fairly high agreement on the general area. Only 40% of non-published voters selected these scales, with moderate confusion from scales 24-33 (although a peak at 32 did mirror those of published researchers). Too few votes from researchers that had published but not conducted scale counts themselves were collected to be interpretable.

This survey was not intended to standardize the position at which researchers should conduct toepad scale counts. The functional significance of toepads changes between species, and therefore that should be an important consideration in respect to the ecological/evolutionary question at hand. Those votes towards the higher end of the spectrum (scales 50-51, comprising a scale count of the entire digit) could be important data for species identification and morphological taxonomy. There could be an opportunity for a neat review/methods paper here, contact me if you are interested in more details!

The second most viewed Anole Annals post of all time is “The proper pronunciation of “anole”” which has been viewed 9,938 times (just 121 views behind the all-time leader. *You’ll have to guess what that one is about. Or click here.).

Well, now there’s a video answering the same question and, frankly, I’m not sure everyone will agree with the answer.

*This post was initially drafted several months ago. In the intervening time, the leading post has gone on a tear, and now is ahead by 1,610 views! Go figure.

I probably would have never said this a few years ago, but penises are absolutely fascinating. The phalluses of terrestrial vertebrates exhibit an incredible diversity of shapes and sizes with some possessing elaborate coils, barbs, bony spines, and multiple lobes. Many of us learn about the rapid evolution of sexual characters in our undergraduate classrooms, but until recently I, for one, did not fully appreciate the striking diversity of this organ until immersing myself in the subject area.

Many biologists study the penis under the umbrellas of different research disciplines, but relatively little work has been performed to explain its anatomical diversity. For example, how many times has a penis/phallus evolved among terrestrial vertebrates? This may seem like a trivial question, but the diversity in form, function, and physiology in the adult phallus actually makes this question difficult to address. Historically there has been much conjecture, but little data to support whether the mammalian penis, squamate hemipenes, and phallus of turtles, crocodilians, and basal birds share a single evolutionary origin or are independently derived. But where comparative anatomy has struggled, comparative developmental biology has recently forged ahead. Within the last several months two independent groups have published a total of seven new research articles that help us resolve the question of phallus homology.

Figure 1 from Gredler et al. 2014 illustrating phallus diversity among amniotes. The darker lines illustrate the sulcus spermaticus which goes on to become internalized in mammals as the urethra.

I previously wrote about a series of five papers published from the Cohn lab (University of Florida) describing the embryology and gene expression patterns for the developing phallus. Since then this group has published a sixth paper synthesizing this wealth of information, using it to lay out a number of outstanding questions regarding phallus development and evolution. More recently, the Tabin lab (Harvard University) published a paper comparing the cellular-level origins of the genitalia in the laboratory mouse, green anole, house snake, chick, and python. I have had the distinct pleasure of working with both groups as their “anole guy.” Although these studies vary widely in their experimental and comparative breadth, together they have shed much needed light on the evolution of vertebrate genitalia. Here my goal is to discuss how this new wave of research changes what we now know, what we don’t know, and what we think we know regarding the evolution of external genitalia among vertebrates. Take a look at the original research papers for details of the developmental analyses, which represent many technical steps forward in our use of anoles as a laboratory model system and intellectual advancements in our understanding of genital development.

During the gradual transition of life onto land, vertebrates evolved the amniotic egg to facilitate their departure from moist environments.

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Let’s hear it for global warming! Ryan Vince Photography’s Facebook page reported that this brown anole was found in Ontario. Probably still too cold there for the festive anoles to survive, but who know’s in a warming world? Here’s what the FB page had to say: “This little hitchhiker is a Brown Anole that has somehow made its way from Florida all the way down to Ontario, Canada (2000km). I found him in a mulch pile at a local aggregate facility. It seems that he had managed to make it through two sets of wood grinders and now resides in a Vivarium here with me.”

And this isn’t the first report of the festive one getting to Canada. Recently, we had a post reporting brown anoles not only in Canada, but Denmark. Next: the World!!!