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JMIH 2014: Effect of Moisture and Substrate on Egg Water Uptake and Phenotypes of Hatchling Lizards (Anolis sagrei)

Following up on yesterday’s post, more research results from the Warner Lab on egg incubation were presented at JMIH. Corey Cates, a masters student from the Warner Lab, presented his data on developmental plasticity in Anolis sagrei. He used an experimental approach to test whether lizards incubated under dry conditions would survive better in a dry habitat than lizards incubated under moist conditions and vice versa. The idea for the study came from the observation that habitat and substrate differs among small islands in Florida. Some islands are scarcely vegetated and have dry substrate consisting of broken shells. Other islands are more densely vegetated and have dark soil that contains organic matter.

Corey collected 128 breeding pairs from four islands and incubated the eggs using the two different substrates. He also tested two different moisture conditions (wet and dry). He found that lizards incubated under wet conditions hatch on average 4-5 days later and hatchlings were significantly heavier than those incubated under dry conditions. In addition, lizards hatch significantly later when incubated in the soil substrate, which retains moisture longer than the broken shells. Corey further tested whether lizards raised under dry conditions have higher desiccation tolerance than lizards from wet conditions. He measured body mass before and after keeping the lizards in a desiccation chamber. Lizards that had developed under wet conditions lost 5% more mass than lizards developed under dry conditions.

Hatchlings incubated under wet conditions lost significantly more mass than hatchlings incubated under dry conditions.

Hatchlings incubated under wet conditions lost significantly more mass than hatchlings incubated under dry conditions.

This suggests, that plastic responses to different developmental conditions have an effect on physiological traits that might increase survival in a specific habitat. To test this, Corey then released the hatchlings on four experimental islands and measured hatchling survival using a recapture method.

Significantly more hatchlings survived in the open, arid habitat when eggs were incubated under dry conditions.

Significantly more hatchlings survived in the open, arid habitat when eggs were incubated under dry conditions.

He found that significantly more hatchlings survived in open, arid habitats when eggs were incubated under dry conditions. No effect of incubation condition on hatchling survival was found in the shaded, moist habitat.

JMIH 2014: Who’s There? The Importance of Familiarity in Discrimination of Avian Calls by the Brown Anole (Anolis sagrei)

brown_anole_auditoryI saw two talks on brown anoles in the same session this afternoon at JMIH. The second reported on the response of brown anoles (A. sagrei) to potential avian predators. Lisa Cantwell presented results of her work with Joe Altobelli and Sandy Echternacht on the behavior of brown anoles exposed to the calls of potential avian predators in a controlled laboratory environment. Cantwell has previously reported that anoles respond more strongly to the calls of predator birds than to white noise or non-predator birds (see also prior work on A. cristatellus in response to predator and non-predatory birds). Cantwell played the calls of four bird species to captive brown anoles and monitored their reactions. The four birds in the study included one species that co-occurs with, and preys upon, A. sagrei: the American Kestrel. The other birds were species that do not co-occur with A. sagrei: the White-rumped Falcon (gotta love the ornithologists and their descriptive common names), the Shikra, and the Lesser Kestrel (this name seems kind of demeaning and should probably be changed). Cantwell tested if the anoles responded more to the predator that they or their ancestors have likely encountered in nature than to the calls of predators that they or their ancestors have likely never encountered. The types of reactions that were viewed as indicative of increased vigilance in the lizards included head shifts, eye opening, and movement around the enclosure. Although Cantwell found that the lizards responded to all of the various bird stimuli at a similar level to white noise, she hypothesized that this resulted from hyper-vigilance in a contrived laboratory environment. She also reported that the lizards responded significantly more quickly to the American Kestrel and that they remained vigilant for twice as long in response to this sympatric predator than they did in response to the non-sympatric predators.

More Research on Female Back Pattern Polymorphisms

Variation in the back patterns of Anolis sagrei in the Bahamas. From Calsbeek and Cox (2010).

The confusing conundrum of the polymorphic females continues. We’ve written about this phenomenon in previous posts [e.g., 1,2]. Within and between populations, female back patterns vary, including lines, stripes, diamonds, blotches, and nothing at all. What is the significance of this variation? In some cases, but not others, females with different patterns use different microhabitats–higher, wider, etc.

The latest contribution features work on the Bahamian island of Eleuthera, where three patterns co-occur. Writing in Herpetologica, Les et al. add a new twist–back pattern variants differ in hindlimb length. But they don’t differ in sprint speed (which is weakly correlated to body size and relative limb length) or to perch diamter. But they do differ in perch height. Another brick in the wall of female pattern polymorphism, but it doesn’t make the picture any clearer.

Here’s the abstract:

The Brown Anole (Anolis sagrei) is a polymorphic species, with females often exhibiting one of three distinct pattern morphs. Efforts to correlate female-limited pattern polymorphism in anoles to ecological or physiological factors have largely been unsuccessful, with such correlations being either inconsistent among species or among populations of a single species. To test the hypothesis that morph types would differ in their response to putative predators, we observed escape behavior in 84 female A. sagrei from Cape Eleuthera (Eleuthera, Bahamas) and tested 103 females for sprint speed. We found differences between morph types in hindlimb span and perch height. Differences in sprint speed were not significant, nor did morphs differ in escape responses. We suggest further studies to determine whether differences between morphs in hindlimb span are genetic or plastic, and, if plastic, what factor might be responsible. We conclude that perching at different heights could be selectively advantageous for different morph types, and that differences among individuals in sprint speed are largely consequences of hindlimb length. Because morphs in this population did not differ in escape responses, we suggest that different dorsal patterns are not linked to specific behaviors that could reduce detection by a potential predator.

 

Green Anole Named Critter of the Year

About time! Read all about it in the St. Augustine Record.

Everything You Ever Wanted to Know about the Beautiful Anolis smaragdinus

smarag

The Catalogue of American Amphibians and Reptiles, produced by the Society for the Study of Amphibians and Reptiles, are “Loose-leaf accounts of taxa (measuring 8.5 x 11 inches) prepared by specialists, including synonymy, definition, description, distribution map, and comprehensive list of literature for each taxon. Covers amphibians and Reptiles of the entire Western Hemisphere. Individual accounts are not sold separately, except where indicated.”

CAAR entries are now freely available online; there are 32 anole species accounts. The latest is by Les and Powell and is a very nice CAAR entry for the lovely Anolis smaragdinus.

Anoles Make Guest Appearance on John Oliver Show

photo

Admittedly, they were in a piece on space geckos, but you gotta’ take fame where you can get it. Catch the clip here before Youtube takes it down.

And note that this is not the first time anoles have been mistaken for geckos by journalists. Let’s not forget the segment on the Sunday Morning CBS show, a misstep for which AA  led the blogosphere in breaking the news and eventually received a mea culpa from CBS.

A Dearth Of Anoles At ISBE And ABS

August 2014 is a good month for behavioural biologists in North America: at the start of the month, the International Society for Behavioral Ecology and the Animal Behavior Society are holding conferences in quick succession in New York City and Princeton respectively. However, Anolis lizards are pitifully underrepresented at these meetings: of the hundreds of talks at these two meetings, a total of zero–yes, zero–are about anoles. This is a tad surprising–plenty of people study the behaviour of anoles, and I was expecting some presentations at these meetings. I’ll be at ABS talking about Sitana, and would love to meet other anole behaviour enthusiasts, so please let me know in the comments below if you’ll be there.

That said, lizards aren’t too badly represented at these meetings: there will be talks or posters on DracoPsammophilus, Phrynocephalus, Sceloporus, Crotaphytus,  Podarcis and Tupinambis. I’ll be blogging about the lizard presentations from ABS, so stay tuned for a behavioural bonanza!

The wonderful Phrynocephalus mystaceus. Photo by Antoshin Konstantin from Wikimedia.

The wonderful Phrynocephalus mystaceus. Photo by Antoshin Konstantin from Wikimedia.

New Special Issue on Morphology and Evolution of Lizards

anatomical record cover

Juan Daza asks: Can you identify this lizard?

He continues:

If you have no idea, it’s not because it’s not an Anolis; in fact, this is an imaginary lizard that was reconstructed based on the remains of a 110 my old fossil from the Gobi Desert and a mosaic of features from different living geckos such as Agamura persica, Pachydactylus rangeiTeratoscincus przewalskii, Hemidactylus turcicus, and Coleonyx variegatus (and check the dromeosaurids roosting at twilight).  This digital illustration drawn by Stephanie Abramowicz is the cover of a March Special Issue from the Anatomical Record: New Advances In Morphology and Evolution of Living and Extinct Squamates [freely available at: http://onlinelibrary.wiley.com/doi/10.1002/ar.v297.3/issuetoc].

The idea of a volume like this started with James D. Gardner and Randall L. Nydam. They wanted to put a collection of papers from the Paleo-session of the past World Congress in Vancouver. Instead, they ended up editing another multi-authored volume entitled: Mesozoic and Cenozoic lissamphibian and squamate assemblages of Laurasia (Palaeobiodiversity and Palaeoenvironments, 93(4), Special Issue).

This volume took a different approach, and we (Scott Miller and I) put together herpetologists and paleontologists from around the world in a volume to present new ideas about morphology and evolution of squamates. This volume is a collection of 18 papers about paleontology, functional morphology, and gross anatomy of lizards and snakes, and includes recent findings from researches from 12 countries (USA, Canada, Colombia, Brazil, Argentina, Spain, France, Italy, Germany, Slovakia, South Africa, and New Zealand).

So please feel free to browse this volume that includes original research papers about the fossil record of lizards and snakes, anatomy of the chameleon’s atlantoaxial complex, pedal grasping capabilities, and pectoral girdle anatomy of anoles, fossil record of the Gekkota, cranial joints of squamates, hemipeneal morphology, brille formation, cranial joints, ancestral morphology and niche modeling of rhineurids, Anguimorpha, and the jaw musculature, and gut morphology of snakes. I hope you find this stimulating and pick morphology today, for a change.

Table of Contents:

The Anatomical Record is Alive With Leapin’ Lizards and Slitherin’ Snakes (pages 337–340)
Kurt H. Albertine and Scott C. Miller

What’s So Special About Squamates? (pages 341–343)
Juan D. Daza and Scott C. Miller

Not Enough Skeletons in the Closet: Collections-Based Anatomical Research in an Age of Conservation Conscience (pages 344–348)
Christopher J. Bell and Jim I. Mead

An Overview of the South American Fossil Squamates (pages 349–368)
Adriana María Albino and Santiago Brizuela

The Atlas-Axis Complex in Chamaeleonids (Squamata: Chamaeleonidae), with Description of a New Anatomical Structure of the Skull (pages 369–396)
Andrej Čerňanský, Renaud Boistel, Vincent Fernandez, Paul Tafforeau, Le Noir Nicolas and Anthony Herrel

Anatomy of the Crus and Pes of Neotropical Iguanian Lizards in Relation to Habitat use and Digitally Based Grasping Capabilities (pages 397–409)
Virginia Abdala, María José Tulli, Anthony P. Russell, George L. Powell and Félix B. Cruz

Geometric Morphometric Analysis of the Breast-Shoulder Apparatus of Lizards: A Test Case Using Jamaican Anoles (Squamata: Dactyloidae) (pages 410–432)
Alexander Tinius and Anthony Patrick Russell

On the Fossil Record of the Gekkota (pages 433–462)
Juan D. Daza, Aaron M. Bauer and Eric D. Snively

To Move or Not to Move: Cranial Joints in European Gekkotans and Lacertids, an Osteological and Histological Perspective (pages 463–472)
Marcello Mezzasalma, Nicola Maio and Fabio Maria Guarino

Relict Endemism of Extant Rhineuridae (Amphisbaenia): Testing for Phylogenetic Niche Conservatism in the Fossil Record (pages 473–481)
Christy A. Hipsley and Johannes Müller

Are Hemipenial Spines Related to Limb Reduction? A Spiny Discussion Focused on Gymnophthalmid Lizards (Squamata: Gymnophthalmidae) (pages 482–495)
Pedro M. Sales Nunes, Felipe F. Curcio, Juliana G. Roscito and Miguel T. Rodrigues

Through the Looking Glass: The Spectacle in Gymnophthalmid Lizards (pages 496–504)Ricardo Arturo Guerra-Fuentes, Juliana G. Roscito, Pedro M. Sales Nunes, Priscilla Rachel Oliveira-Bastos, Marta Maria Antoniazzi, Jared Carlos and Miguel Trefaut Rodrigues

A New Miniaturized Lizard From the Late Eocene of France and Spain (pages 505–515)
Arnau Bolet and Marc Augé

Comparative Anatomy of the Lower Jaw and Dentition of Pseudopus apodus and the Interrelationships of Species of Subfamily Anguinae (Anguimorpha, Anguidae) (pages 516–544)
Jozef Klembara, Miroslav Hain and Karolína Dobiašová

Unusual Soft-Tissue Preservation of a Crocodile Lizard (Squamata, Shinisauria) From the Green River Formation (Eocene) and Shinisaur Relationships (pages 545–559)
Jack L. Conrad, Jason J. Head and Matthew T. Carrano

Postnatal Development of the Skull of Dinilysia patagonica (Squamata-Stem Serpentes) (pages 560–573)
Agustín Scanferla and Bhart-Anjan S. Bhullar
Article

Homology of the Jaw Muscles in Lizards and Snakes—A Solution from a Comparative Gnathostome Approach (pages 574–585)
Peter Johnston

A Model of the Anterior Esophagus in Snakes, with Functional and Developmental Implications (pages 586–598)
David Cundall, Cassandra Tuttman and Matthew Close

Video of Anolis lemurinus Displaying

Short video of a cool, but underappreciated, anole.

Anole Animated Cartoon

Page 117 of 154

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