<img src="https://www.anoleannals.org/wp-content/uploads/2020/05/Anole-Annals-Logo-375w.png"> Anole Annals

The journal Herpetological Review, published by the society for the Study of Amphibians and Reptiles, frequently has interesting anecdotal reports of natural history observations of anoles. This quarter’s edition has two: nocturnal activity in Anolis cristatellus and prey stealing behavior in Anolis sagrei. Here is a synopsis:

Dean and Jennifer Metcalfe report on nocturnal behavior of A. cristatellus wileyae observed (while perhaps on vacation) at the Nanny Cay Resort and Marina on Tortola, British Virgin Islands. The authors observed that the subject anole had navigated the interior of their hotel room in near darkness after dusk, selecting a nocturnal perching site on a lampshade. They suggest that this is similar behavior to that of an anole selecting an arboreal perch site at dusk. Two questions come to mind though. First, whether the room was completely dark- as the authors acknowledge that some light might have been entering the room- and whether the animal came from the outside into the room to perch or was residing in the room. Second, the author mentioned that this was the only anole seen on Tortola during her brief stay, which is also a bit unusual as the species should be abundant there. This might not add much to our understanding of anoles, but it certainly raises some questions about the co-habitation of humans and anoles.

The second note comes from David Delaney, a master’s student in Dan Warner’s lab at UAB, and friends, who report on an opportunistic A. sagrei in Ormond Beach, Florida. The anole had apparently been observing a predation attempt of a spider-wasp on a funnel-web spider. To summarize, the wasp attacked and envenomed the spider, captured it, and began dragging it across the ground. At this point the anole jumped to the ground, grabbed the spider, and took it up the tree to eat it. The wasp, likely disappointed, fled the area to hunt again.

Metcalfe, DC and JE Metcalfe. 2014. Anolis cristatellus wileyae (Vrigin islands Crested Anole). Nocturnal Activity. Herpetological Review 45: 323-324.

Delaney, DM et al. 2014. Anolis sagrei (Brown Anole). Prey stealing behavior. Herpetological Review 45: 324-325.

JMIH 2014: Relative Contribution of Genetic and Ecological Factors to Morphological Differentiation in Island Populations of Anolis sagrei

On August 7, 2014

Hanna Wegener, a student with Jason Kolbe at the University of Rhode Island (and an Anole Annals contributor), presented a poster at JMIH on her efforts to identify the factors that drive morphological differentiation among Anolis sagrei populations found on 16 Bahamian islands near Staniel Cay. Hanna investigated morphometric, ecological, genetic, and demographic variation among these populations and, unlike many previous studies, considered variation in both males and females. Although Hanna did find significant morphometric variation among islands and between sexes, she did not find the significant correlation between morphometric variation and habitat use reported in prior work. She also did not find a significant relationship between morphometric and genetic variation. She did, however, find that population density influences morphometric variation, with lizards living at higher population densities having significantly longer heads than those found on lower density islands. Because these lizards on densely populated islands are also more likely to exhibit evidence of injury from other anoles (e.g., loss of limbs, digits, or claws), it is possible that their longer heads may indicate a response to intra-specific competitive interactions. However, interpretation of these results remains complicated because there is not a direct connection between injury and intra-specific competition, and the lizards on densely populated islands had longer heads, but not the wider heads that would have been expected if the goal of their morphometric shift was to increase bite force. Hanna undoubtedly has many more exciting questions to investigate with her ongoing research.

Anole Field Research Blogs

By Jonathan Losos

On August 6, 2014

Great photos on Adventures Down South

Where do anoles poop? Will they chase laser points? Find out on Casey Gilman’s new blog on her Florida field research, Adventures Down South. Meanwhile, Chipojolab keeps the world abreast of goings-on in the Leal Lab. Most recently–Leal back in the Bahamas and multiple lab members cavorting in Puerto Rico! And Ambika Kamath’s afoot with her field crew in Gainesville, dodging frisbees and fire ants in quest of the wily festive anole. Finally, at Lizard and Friends, Michele Johnson talks about Puerto Rican anoles that are biting off more than they can chew. Or are they?

Do you have a blog on your research? If so, let us know!

Field laboratory in Puerto Rico. Read all about it in Chipojolab.

JMIH 2014: The Ultrastructure of Spermatid Development within the Anole, Anolis sagrei

On August 5, 2014

In a poster at JMIH 2014, Jonathan Clinger of Austin Peay State University found that spermiogenesis (the final step of spermatogenesis during which spermatids develop into mature spermatozoa) in Anolis sagrei is fairly similar to that previously reported in A. carolinensis.

JMIH 2014: Performance Loss Does Not Deter Anoles from Using Artificial Perches

By Hanna Wegener

On August 4, 2014

Andrew Battles from the Kolbe Lab gave a talk at JMIH presenting data on performance-habitat relationships comparing lizard performance on rough and smooth surfaces. The data were collected on Guana Island in the British Virgin Islands using Anolis cristatellus and A. stratulus as study species. Andrew and his advisor, Jason Kolbe, were interested in whether lizards perform differently on artificial and natural surfaces.

Major differences between natural and urban habitas

Major differences between natural and artificial habitats

They used three different running tracks (37°-incline rough track, 90°-incline rough track, 90°-incline smooth track), assuming that artificial surfaces are smoother than natural ones. The rough tracks consisted of a board covered in window screen and the smooth track was a plain 2-by-4 board. They used a high-speed camera to measure maximum velocity, how often a lizard paused during the run and how often it slipped. While both species ran significantly slower, paused and slipped more often on the smooth surface, A. cristatellus performed even worse than A. stratulus. Andrew and Jason then conduced a field survey to test whether lizards in a human-modified habitat use both artificial and natural perches. In addition, they rated roughness of natural and artificial perches. When both types of perches were available, lizards used artificial perches more often than natural ones.

In human-modified habitats, lizards were found mostly on artificial perches

This is surprising, because artificial perches are significantly smoother than natural ones and lizards perform worse on smooth surfaces. Possible explanations are that other factors such as food availability and/ or predation may drive habitat selection on artificial substrates.

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

By Hanna Wegener

On August 4, 2014

In All Posts, New Research

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.

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.

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: Effects of Natural Incubation Temperatures on Development and Phenotypes of the Lizard Anolis sagrei

On August 2, 2014

Yesterday at JMIH, Phillip Pearson reported results from work conducted with his thesis adviser at the University of Alabama, Birmingham Daniel Warner. Pearson investigated the impact of incubation environment on the brown anole (Anolis sagrei), and the effects of incubation in shaded versus open habitat and early versus late season in particular. Pearson reported several significant differences between the eggs (and resulting hatchlings) incubated under these two conditions. He specifically reported longer incubation intervals under early season and shaded conditions, smaller hatchling size under shaded conditions and better performance of hatchlings at 1 and 3 weeks for the eggs incubated under the late season regime. Performance of hatchlings was quantified as their speed and the number of times they stopped during a performance trial. This work is the latest in a string of interesting studies from the Warner Lab on the impact of incubation conditions on anoles. I was going to provide links to previous posts on Anole Annals about the Warner Lab‘s work, but there are so many that I’ll just suggest that you type “Warner” into the search box at the top of the page and enjoy for yourself.

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

On July 31, 2014

I 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.

JMIH 2014: Using Biological Invasions to Model the Fundamental Niche: A Case Study Using the Cuban Brown Anole (Anolis sagrei)

On July 31, 2014