Reports Pat Shipman in Little Cayman, adding “Notice the difference between her expression and his. Anolis maynardi on Little Cayman, just after a nice rain.”
And notice that sexual dimorphism in snout length!
Author: Jonathan Losos Page 60 of 133
Professor of Biology and Director of the Living Earth Collaborative at Washington University in Saint Louis. I've spent my entire professional career studying anoles and have discovered that the more I learn about anoles, the more I realize I don't know.
Photo by Jake Scott
Some people think so, such as this posting on the Association of South Eastern Herpetogists website. I have my doubts about the presence of porcatus in Florida. Anolis carolinensis, after all, is derived from A. porcatus. In reality, it is simply a population of A. porcatus, perhaps smaller than most of their Cuban comrades. Suppose for some reason A. carolinensis started growing larger–wouldn’t they look like the green anoles on Cuba? Anyone have thoughts on whether Cuban porcatus are really in Florida and, if so, how easy it is to identify them?
Photo by Christopher Kirby
Here’s another putative porcatus, this one photographed by Christopher Kirby. Those heads are pretty mean looking, I’ll grant that. Several other photos are also on the ASEH website.
Check out this green anole photographed at the Archbold Biological Station in Florida by Nick Fletcher, participating in a Cornell University field trip led by Harry Greene.
Green anole. Photo by Nick Fletcher.
Photo by Nick Fletcher.
And here’s one more by Nick, taken a day later.
Photo by Nick Fletcher.
From the pages of Sports Illustrated, 25 years ago today
That’s my thumb! Ain’t she a beauty?
A few months ago, I ran into Nicholas Dawidoff, the author of the fabulous new book Collision Low Crossers: A Year Inside the Turbulent World of NFL Football. Seeing Nicholas reminded me of the article he wrote for Sports Illustrated at the very dawn of his writing career, 25 years ago today. The article was on the then developing field of performance studies, measuring the sprinting, jumping, clinging and other capabilities of small ectotherms, and featuring none other than yours truly, as well as Ray Huey, Al Bennett, and Sharon Emerson. Written tongue-in-cheek, but accurately and respectfully, the article was a very nice overview of that emerging field of study. It’s worth checking out the article just to see the wacky pictures taken by the SI photographer sent out on assignment to Seattle and Berkeley.
Inexplicably, the article didn’t make the cover
Photo courtesy Marissa Pierce
Blurb: “This guide will allow nearly everyone with an interest in amphibians and reptiles to collect and store samples for genetic analyses. It is written at a level appropriate for people with a basic background in biology, including professional scientists moving into a new project as well as wildlife managers, conservation biologists, ecologists, and others working on herpetological projects. The book should also be useful for advanced undergraduates and graduate students just starting their research careers.”
See more at the SSAR book website.
Price: $11
Anolis pentaprion taxiing down the runway on a canopy tower at the La Selva Biological Station in Costa Rica. Photo by Vinicio Paniagua.
Draco, the flying dragon, has borrowed an anole dewlap, so it’s only proper that anoles return the favor by developing gliding capabilities. It’s been long rumored that Anolis pentaprion, a twig anole from Central America, will launch itself off of perches in canopy and glide away, but now Steve Overbauer, Vinicio Paniagua, Craig Guyer and Mo Donnelly have documented just that in an interesting herpetological natural history note that appeared in the last issue of last year’s volume of Herp Review (Vol. 44, pp. 677-678). Here’s what they have to say:
“Lizards with gliding or directed aerial descent behaviors are well known from the Old World Tropics (e.g., Draco, Ptychozoon), and snakes and frogs exhibiting these behaviors are found both in the Old and New World Tropics (Dudley et al. 2007. Annu. Rev. Ecol. Evol. Syst. 38:179–201). However, lizards showing directed aerial descent have not been reported from the New World Tropics. Here we report on directed aerial descent capability and behavior in Norops pentaprion, a canopy lizard from eastern Costa Rica, southern Nicaragua, and western Panama (Köhler 2010. Zootaxa 2354:1–18).
The initial discovery of this behavior in N. pentaprion was serendipitous in July 2001 when an individual was captured on a walk-up meteorological tower at canopy level (~ 25 m) at La Selva Biological Station in the Atlantic lowlands of Costa Rica. After identification, the animal was returned to the original location on the tower, but upon release to a horizontal tower brace, it executed a controlled aerial descent to a tree in the distance below. Individuals of N. pentaprion have been occasionally observed on our meteorological towers subsequent to our first observation of directed aerial descent. The lizards are typically at canopy level but are sometimes found well above the canopy on the highest levels of the towers (up to 42 m). While the typical response of N. pentaprion to the presence of personnel on the tower is to race down the tower or hide on the opposite side of vertical supports, the animals will occasionally jump from the tower to escape when approached. Since 2001 we have observed directed aerial descent by N. pentaprion from canopy towers on several occasions. In at least two instances the lizard landed at lower levels on the tower, but in other occurrences they covered substantial distance to adjacent trees including aerial rotations of near 180º. During more than one observation, animals appeared to glide with near-horizontal trajectories towards termination of the descent. Similar to some snakes, frogs, lizards, and ants showing directed aerial descent, N. pentaprion does not have strongly specialized features associated with gliding behavior such as skin flaps, skin extensions, or webbed feet. Norops pentaprion has a relatively flattened head and wide body. During aerial descent this lizard proceeds headfirst, with limbs partially extended and the body strongly flattened, a position that may take advantage of regions of relatively loose skin along the sides of the body (Guyer and Donnelly 2005. Amphibians and Reptiles of La Selva, Costa Rica, and the Caribbean Slope, Univ. California Press, Berkeley, California. 299 pp.).
At La Selva Biological Station this species is uncommon in the understory and is usually found on trees limbs. Norops pentaprion is a member of a closely-related group of anoline lizards subjected to a recent analysis of morphology and morphometrics (Köhler, op. cit.); these related taxa share similar body size characteristics with N. pentaprion and are frequently arboreal. Future observations of some of these species may result in the discovery of similar directed-aerial descent behavior. Canopy pioneer Donald Perry reported lizards with a rose dewlap parachuting between trees in the canopy in Costa Rican forests (Perry 1986. Life Above the Jungle Floor, Simon and Schuster, Inc. New York, New York. 170 pp.), but the species was not identified. In their description of Norops pentaprion, Guyer and Donnelly (op. cit.) indicated that parachuting behavior likely occurs in this species on the basis of our initial observations and those of Perry. Our repeated observations verify directed aerial descent in this species and confirm that the lizard observed by Perry was N. pentaprion, the only lizard in the region with magenta dewlap coloration.”
When it rains, it pours. Research on the immense diversity in anole chromosomes was rampant in the 1970’s and early 1980’s, and then…nothing. Until, that is, the last two months. Not one, but two, papers appeared in Evolution, and now AA has learned of a paper on chromosomal variation in Norops clade anoles, recently published in Zoological Studies (click for a downloadable pdf). The paper, by Castiglia et al., examines karyotypes in Norops anoles and argues that karyological variation is in some cases consistent with our understanding of phylogenetic relationships within the group.
Abstract
Background: Neotropical lizards, genus Anolis (Polychrotidae), with nearly 380 species, are members of one of the most diversified genera among amniotes. Herein, we present an overview of chromosomal evolution in ‘beta’ Anolis (Norops group) as a baseline for future studies of the karyotypic evolution of anoles. We evaluated all available information concerning karyotypes of Norops, including original data on a recently described species, Anolis unilobatus. We used the phylogeny of Norops based on DNA sequence data to infer the main pattern of chromosomal evolution by means of an ancestral state analysis (ASR).
Results: We identified 11 different karyotypes, of which 9 in the species had so far been used in molecular studies. The ASR indicated that a change in the number of microchromosomes was the first evolutionary step, followed by an increase in chromosome numbers, likely due to centric fissions of macrochromosomes. The ASR also showed that in nine species, heteromorphic sex chromosomes most probably originated from six independent events.
Conclusions: We observed an overall good correspondence of some characteristics of karyotypes and species relationships. Moreover, the clade seems prone to sex chromosome diversification, and the origins of five of these heteromorphic sex chromosome variants seem to be recent as they appear at the tip nodes in the ancestral character reconstruction. Karyotypic diversification in Norops provides an opportunity to test the chromosomal speciation models and is expected to be useful in studying relationships among anole species and in identifying cryptic taxa.
Note the arm waving and tongue protrusion!
httpv://www.youtube.com/watch?v=OP3rnPQJT6A
Thinking of setting up a room to maintain and breed lizards for research projects? Back in 2011, the good folks in the Glor Lab–which has done a stupendous job at breeding A. distichus–shared their accumulated knowledge in an 11-part series. Given the fog of memory, it seemed like a good time to remind the world of the existence of this primer, and put the links all together in one place.
So, with no further ado, here are the 11 posts in the “Evolution of a Lizard Room” undecology:
1: Introduction
10: Custom cages for breeding experiments
11: Butterfly Cages
For another source of information, check-out the manual put together by the Brodie Lab at the University of Virginia.