Artificially Isolated Populations of Anoles

Photograph by Craig Berg

During a spring trip to the Dominican Republic, I spent a few nights at a high-rise hotel along the “beach” in Santo Domingo. The hotel had a concrete imprint, totally devoid of grounds. It faced a busy four-lane road and the “malecón.” A narrow band of greenery, often a single row of trees, separates the far side of the street and the high-tide mark. Anolis distichus and naturalized A. porcatus occur in small numbers along that green band. Some ornamental plantings on the fifth floor, accessible only by scaling the outside of the hotel or through the building or parking garage, supported a small number of A. distichus. I observed at least ten individuals engaged in male-male interactions, mating, and movements across a paved driveway to an even smaller planting with a few shrubs paralleling the drive. Although these individuals (or their ancestors) could have colonized this isolated pocket on their own, I believe that it is much more likely that they were introduced with the plants (a few of which were still in plastic pots). I’m guessing that this scenario is not unique and that similar isolated populations of various species exist in comparable situations throughout the islands (e.g., A. cristatellus occupies analogous, albeit not quite such isolated, plantings at the international airport in San Juan, Puerto Rico). Although some gene flow might occur when new plantings arrive, these tiny isolates, composed of no more than a few dozen individuals, are probably genetically isolated and subject to considerable inbreeding. Has anyone ever examined the lizards in such tightly constrained artificial pockets of habitat? That they exist at all, much less appear to function for extended periods, is testament to the extent to which at least some anoles adapt readily to extremely altered situations.

Young Women in Science: The Anole Connection

A young women in science booklet produced by Science/AAAS in collaboration with L’Oreal.

Beauty + Brains Puts Anoles in the Spotlight

Who could turn down a good looker with something upstairs, especially wearing a gorgeous shade of green? Not the Economist, which featured Leal and Powell’s study of anole cognition in this week’s edition (no, it’s not the article on the orgasmatron). See the article here.

In fact, anole-o-mania has caught on, with reports in print, online, and on radio and TV. Most recent is today’s piece in the Science Times.

According to the Life Science Log, this is among the most cited news reports in the last week. For a full list of media coverage–with more still on the way–check here.

Bonus points: who remembers the orgasmatron?

p.s. A video of the lizards problem-solving is now available on YouTube

A Hearty Meal Impairs A Lizard’s Jumping Ability

Jumping green anole. Photo from http://www.people.umass.edu/chiyun/Site/Research.html

Ever try playing softball after a barbecue? Doesn’t work so well, does it? Now imagine trying the long jump–just the thought makes me a little queasy. But animals in the wild have to do this all the time. Does it affect their performance? Lizards and other animals are known to have their running abilities diminished by carrying a large load, such as a meal or eggs, but no one previously has looked at the effect of increased weight on jumping.

Until now. In a recent paper, Kuo et al. increased the weight of green anoles 30% by wrapping a weighted cloth around their midsection and then induced them to jump (pdf of the paper here). As a control, they wrapped light paper around the lizard in the same manner. As you might expect, the encumbered anoles were less proficient leapers; jump distance declined 18% and takeoff speed 10%. However, their accuracy, as judged by ability to land on a target, was not affected.

Anoles In Space

The Space Shuttle Atlantis lifting off from the horizon. Fellow lizarders Todd Campbell (L) and Casey Gilman (R) look on.

On July 8, we took a break from field work here in Florida to watch the launch of NASA’s last Space Shuttle mission. During the build up to the launch, I thought a lot about the end of the Shuttle program and of the scientific frontier that we are, at least temporarily, leaving. Naturally, my thoughts eventually turned to whether anoles have ever been to space.

New Reviews of Lizards In An Evolutionary Tree

More than two years post-publication, reviews of Lizards in an Evolutionary Tree continue to trickle in. The most recent appeared in Austral Ecology and Herpetological Review. See all 12 (of which we’re aware–know of others?) here.

A Non-Anole Grass-Bush Ecomorph?

I have long thought that the Asian lacertid lizard, Takydromus sexlineatus, is the best example of a non-anole species that corresponds to one of the anole ecomorphs. Extraordinarily long in tail, slender in body, light brown in color with a light-colored lateral stripe, this grass-dwelling lizard seems a dead ringer to a grass-bush ecomorph. This, of course, leads to many questions, not least of which is: if Takydromus somehow were juxtaposed with some ecomorphs, how would they interact?  Now we know the answer.

They’d ignore each other. Or at least, they’d do so within the confines of a small
Petsmart vivarium where they are commonly sold.

Anole Research Cleans Up on Awards at JMIH

A figure illustrating dewlap color variation in the distichus species group from Anthony Geneva's award winning poster.

Two posters on anole evolution presented at JMIH last weekend were honored with SSAR poster awards.  Anthony Geneva, a PhD student at the University of Rochester took home the prize in the Evolution, Genetics, & Systematics category for his poster on “A Multi-locus Molecular Phylogeny of Distichoid Anoles.”  Mingna Zhuang, an undergraduate researcher at UC Berkeley, won in the Ecology, Natural History, Distribution, & Behavior category for her poster on “Comparative Gliding Performance of Anolis carolinensis and Anolis sagrei.”  Although not on anoles, it also bears noting that Daniel Scantlebury’s study of adaptive radiation in Sphaerodactylus – which has been inspired partly by work on Anolis – won the SSAR’s Henri Seibert Award for best student talk on Evolution/Systematics.  Congrats to Anthony, Mingna, and Dan!

Is An Anole Smarter Than a Fifth Grader?

Manuel Leal and Brian Powell have just published a paper in Biology Letters demonstrating that lizards are smart. Before getting to the details, though—here’s the important point: check out the videos! They’re pretty amazing (here, scroll down and click on the videos).

Here’s the story: working with the Puerto Rican trunk-crown anole, A. evermanni, Leal and Powell presented lizards with an experimental apparatus in their home cages with two wells, in one of which was a dead phoenix worm (whatever that is). Next to the well with the worm was a little round disc similar to a poker chip. The lizards learned to go to the well and find and eat the worms. Then the experimenters placed the chip halfway over the well. Again, no problem.

Now comes the cool part. The experimenters completely covered the well containing the worm with a blue chip. Remember, these are Anolis lizards that usually find their prey by looking for movement—they don’t go digging around in the underbrush. Still, four out of the six lizards figured out how to get the mealworm: two of them bit the chip and removed it from covering the well, while two others figured out how to use their snouts as a lever to flip the chip off the well. This is pure problem-solving, and it uses novel behaviors, rather than simply transferring a natural behavior to a new context! And the two lizards that failed to get the worm came up with their own solution, hitting the center of the chip with their snout—but this was ineffective in dislodging the chip.

Once the lizards had learned to find the worm under the chip, the experimenters then conducted a discrimination trial, giving the choice of a blue chip and a yellow chip. Without error, the lizards always went to the blue chip; subsequently, they were presented a blue chip versus a blue-and-yellow chip, and they still had no problem.

Pretty amazing for a lizard, if you ask me, but it gets even better.

A Primer on Filming Anole Behavior – Part 1(b)

Back in my first post on this topic, I described some of the equipment I use to film anole behavior. I ended with a promise of a second entry replete with example videos to outline specific techniques I use to get useful footage. I also wrote that hi-definition videos are troublesome to play, let alone edit, on many computers. Well, the egg is partially on my face, because I’ve been having trouble finding a good way to edit standard definition videos. Playback, the important part for my research, is flawless, but iMovie doesn’t like to deal with the files.

Rather than balk at this challenge any longer, I decided to turn to the community (that’s you, Anole Annals reader) for help. So those of you out there who have done video editing, can you recommend a program to use (or to avoid)? Cost and ease of learning are prime considerations for me right now. Please leave comments, and thanks in advance for any input.

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