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Anole Calendar Photo Contest 2020 – Time to Vote!

Aryeh Miller and Ansley Petherick

The Finalists Are In!

Thanks to all who submitted photos for the Anole Annals calendar contest–we received lots of great submissions! We’ve narrowed it down to the top 32, and now it’s time for you to vote! Here’s a slideshow of the finalists:

 

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Vote Now!

Choose your 6 favorites in the poll below. You can right-click on the thumbnail to view full-size images in the poll, check the box next to your picks. You have 13 days to vote – poll closes on 12/13/20 (a Sunday) at 11:59pm. Spread the word!

carolinensissagrei hanky-panky redux

 

Photo by Rachel Easton.

Periodically, we here at Anole Annals get reports of mating between green and brown anoles. Usually, it turns out to be a case of misidentification–often the “brown” anole is really a green anole in brown color phase, but sometimes it actually does happen. The most recent report comes from reader Rachel Easton, who tells the story of the picture above: “I’ve had them for a few weeks but they lived together at the pet store for months before I had them.  They are in a 20 gallon in my greenhouse. This is the first time I’ve witnessed the mating behavior. I moved their tank to another location and about 3 minutes later they were mating. I occasionally see them displaying their throats at one another but I assumed it was a territorial dispute over the best basking spot.”

#DidYouAnole – Curly-tailed Anoles


Photo by Steven Kurniawidjaja, iNaturalist

Hello! Hope you had a good Thursday!

I moved #DidYouAnole and shortened it for this week because of the holiday. We aren’t talking about one specific anole (or lizard) today, but just ideas on an observed behaviour.

Recently someone posted a picture of curly-tailed Brown Anole (Anolis sagrei) noting that they had been seeing this recently with the brown anoles in their area.

This intensity of tail curling, while typical of curly-tailed lizards (they’re named for it!), isn’t all too uncommon in anoles. For curly-tailed lizards, their tail curl is possibly used as part of anti-predator behaviour, meaning it helps them distract a predator away from their bodies, or makes them look bigger. Anoles also use their tails in a similar way, waving them during aggressive displays against other males and predators.


Photo by Bill Lucas, iNaturalist

Lizards use their tail in various kinds of signaling and tail curling is one that we have been observing but don’t quite know a lot about yet! Has anyone else observed this or have any ideas about tail curling behaviour?

Clouded Anoles: How Islands Affect Morphology

Ecogeographical rules attempt to simplify ecological and evolutionary processes that shape morphology. In a cool study published this summer in Current Zoology, Anaya-Meraz and Escobedo-Galván (2020) examine the combined effect of Rensch’s Rule and van Valen’s Island Rule in Clouded Anoles. Specifically:

Rensch’s Rule: within lineages, sexual dimorphism decreases in magnitude with increased body size when females are the larger sex but increases in magnitude when males are the larger sex.

The center black line indicates 1:1 male to female size, the top line and bottom lines indicate male- and female-biased size dimorphism, respectively. *Adapted from Piross et al. 2019.

van Valen’s Island Rule: describes the tendency of diminutive and large mainland species to trend toward gigantism or dwarfism on islands, respectively, due to competitive factors.

*Adapted from Lomolino, 2005

In their paper, Anaya-Meraz and Escobedo-Galván ask, how does Clouded Anole (Anolis nebulosus) sexual size dimorphism change when the Island Rule could be in effect?

Using 305 Clouded Anole museum specimens, they found that sexual size dimorphism differs between the mainland and island populations. While all populations revealed variation in the degree of sexual size dimorphism, populations on the Islas Tres Marías uniformly possess male-body size bias. But on the mainland, 40% of the populations had the opposite pattern, female-body size bias.

Intriguingly, Anaya-Meraz and Escobedo-Galván note that in the Clouded Anole, island males spend almost 50% more of their waking period engaged in some form of social interaction (Siliceo-Cantero et al. 2016). This is offered as an explanation for why male Clouded Anoles also have larger dewlaps among the Tres Marías populations.

In lizards, the Island Rule may not necessarily stand out as a trend (Meiri, 2007), but we see from Anaya-Meraz and Escobedo-Galván’s study that male Clouded Anoles are larger on islands. On the Antillean Islands, the magnitude of sexual size and shape dimorphism of anoles decreases with increased anole species diversity (Butler et al., 2007). The Islas Tres Marías populations follow this pattern in having increased sexual size dimorphism when not competing with other anole species.

*Adapted from Poe et al. 2017.

Overall, Clouded Anole body and dewlap sizes are larger in insular populations while Rensch’s Rule does not show a clean pattern in this species. However, as noted by the authors, it is important to consider the adaptive force of being on an island versus the ancestral condition. To truly understand morphological evolution within a species and across the genus we need to know body size trends of closely related species. Moreover, some researchers are discouraging studies that determine the universality of ecogeographical rules in favor of integrative approaches based around hypothesis testing (Lomolino et al. 2006, Lokatis & Jeschke, 2018).

What do you think? Is there room for using ecogeographical rules within an integrative framework (See Benítez-López et al. 2020)? Or do ecogeographical rules obscure true drivers of adaptation?

References:

Anaya-Meraz, Z. A., and A. H. Escobedo-Galván. 2020. Insular effect on sexual size dimorphism in the Clouded Anole Anolis nebulosus: when Rensch meets Van Valen. Current Zoology, doi: 10.1093/cz/zoaa034.

Benítez-López, A., L. Santini, J. Gallego-Zamorano, B. Milá, P. Walkden, M. A. J. Huijbregts, and J. A. Tobias. 2020. The island rule explains consistent patterns of body size evolution across terrestrial vertebrates. bioRxiv 2020.05.25.114835. Cold Spring Harbor Laboratory.

Butler, M. A., S. A. Sawyer, and J. B. Losos. 2007. Sexual dimorphism and adaptive radiation in Anolis lizards. Nature 447:202–205. Nature Publishing Group.

Lokatis, S., and J. M. Jeschke. 2018. The island rule: an assessment of biases and research trends. Journal of Biogeography 45:289–303. Wiley Online Library.

Lomolino, M. V. 2005. Body size evolution in insular vertebrates: generality of the island rule. Journal of Biogeography 32:1683–1699.

Lomolino, M. V., D. F. Sax, B. R. Riddle, and J. H. Brown. 2006. The island rule and a research agenda for studying ecogeographical patterns. Journal of Biogeography 33:1503–1510.

Meiri, S. 2007. Size evolution in island lizards. Global Ecology and Biogeography, 16:702-708.

Poe, S., A. Nieto-montes de Oca, O. Torres-Carvajal, K. De Queiroz, J. A. Velasco, B. Truett, L. N. Gray, M. J. Ryan, G. Köhler, F. Ayala-Varela, and I. Latella. 2017. A Phylogenetic, Biogeographic, and Taxonomic study of all Extant Species of Anolis (Squamata; Iguanidae). Systematic Biology 66:663–697.

Piross, I. S., A. Harnos, and L. Rózsa. 2019. Rensch’s rule in avian lice: contradictory allometric trends for sexual size dimorphism. Scientific Reports 9:7908. Nature Publishing Group.

Siliceo-Cantero, H. H., A. García, R. G. Reynolds, G. Pacheco, and B. C, Lister. 2016). Dimorphism and divergence in island and mainland Anoles. Biological Journal of the Linnean Society, 118:852–872.

This post was originally published on biomh.wordpress.com.

#DidYouAnole – Anolis proboscis


Photo by Osoandino, iNaturalist

This week’s anole is one of three recorded species of anoles with a proboscis, the Pinocchio Anole, or Ecuadorian Horned Anole. The other two proboscid species being Anolis phyllorhinus and Anolis laevis.

Anolis proboscis has been featured on this website several times and is well loved here, so you may already know that only the males have the proboscis.
They are capable of raising and lowering their appendages and use it for attracting mates. They move their heads side to side in displays referred to as ‘proboscis flourishing’ (Quirola et al. 2017). Males also stimulate females during courtship, by rubbing the nape of their necks with the appendage. The horn can’t be used as a weapon for fighting other males as it is very flexible, capable of folding right over (Losos et al. 2012), but they display their horns during these interactions, raising them, most likely to appear larger and more intimidating to the rival male. Their dewlaps are small, which is common in anoles with other physical signals, but more research is needed into the uses of the appendage to further confirm its uses.


Female Pinocchio Anole, photo by Nelson Apolo, iNaturalist

The Pinocchio Anole males, unlike other proboscid anoles, are born with a small horn. Why do they have the horn so early? We don’t know… yet!

This anole is very hard to find, actually even being assumed extinct after going unseen by locals and visiting scientists alike, after specimens were collected in 1966, until accidentally being spotted by a birdwatching group in 2005 when a male crossed the road. They typically prefer dense vegetation but on occasion may be found active on the ground. Pinocchio Anoles are endangered, and only found in the protected forest reserves that make up their range in Ecuador, where they are endemic.

No Need for Artificial Light: Diurnal Anoles Active under Lunar Light

Anolis cristatellus predating on Eleutherodactylus martinicensis; photo taken by Jeanelle Brisbane

In the (sub)tropics of the Western Hemisphere, it is not uncommon to come across sleeping anoles while strolling around at night in (partially) vegetated areas; they are after all considered diurnal. It was therefore quite a shock when active anoles appeared in the beam of our headlights during the nights of 18 January and 16 April 2019 on the Commonwealth of Dominica. On the first night, we observed how a juvenile Anolis cristatellus (non-native) jumped from one grass style to the next and successfully caught a fly; on the second night, the adult A. cristatellus had a still alive and resisting, frog (Eleutherodactylus martinicensis) in its mouth (see photo).

An increasing number of anole species are being found to utilize artificial light sources after sunset, and thereby extend their activity period, allowing increased growth and fecundity. What made our encounter especially unsuspected was the absence of artificial light in the area we were surveying for the removal of newly arrived alien species. Instead, these nights (waxing gibbous with 91.7-92.9% visibility) were close to the full moon, and without cloud cover. Our observations were at 19:59 and 20:40h, almost 2 hours after the end of astronomical twilight; it was night.

The area of our observations consists of several abandoned plots nearby the harbor, overgrown with grasses, vines, and bushes. The edges of this open area are partially made up of a single line of trees, shorter than 7 m in height.

Our observations indicate a potential understudied part of anole ecology, though more observations are needed to understand the occurrence of this behavior, both within and among species. However, ex-situ, some authors have already demonstrated that anoles show activity under moonlight conditions, which appeared more evident for shade-adapted species.

In our paper just published in Neotropical Biodiversity, we discuss several to-be-tested hypotheses and address how our observations could shed new light on anole predation by nocturnal predators, like owls and bats. Beyond anoles, observations of nocturnal activity by diurnal reptiles have been reported on some occasions. The observations of this behavior in Anolis are of special importance given the large body of literature and understanding of these model species; allowing the scientific community to test hypotheses and move beyond observational reports.

Excitingly, since the publication of our work we have been in contact with enthusiast readers of which one indicated to have observed moonlight-facilitated activity as well but did not write that up, yet.

Wacky Looking Green Anole from Gainesville

Matt R. Whiles, Chair and Professor in the Soil and Water Sciences Department at the University of Florida provides these details:

Specimen was not captured, just photographed by my wife Lindsay Hsieh, who is familiar with Anolis and recognized that it was different looking.  Observed in Alachua county FL, west of Gainesville in a horse barn facility – coordinates: 29O 41’08”N 82O 30’18”W;  date was November 10 2020.  A. carolinensis are common on the barn, but none we’ve seen look like this.  The owners of the facility routinely haul horses back and forth from Gainesville to south Florida, so could be a transplant.”

He then asks: “I’ve seen thousands of A. carolinensis, and never one like this.  Do you think this is just a color/pattern display, or would this individual always look like this?  We are keeping an eye out for it again and will try to collect it if you want the specimen.”

Thoughts, anyone (including interest in the specimen should it be seen again)? My guess is that these are not  permanent markings; the block spot on the head and the hint of an erected nuchal (neck) crest suggests a stress response; perhaps the lizard had just been fighting. Indeed, Dr. Whiles clarified in a subsequent email: “I’ve certainly seen the black spot form on stressed individuals, but never the full patterning.  To add to your hypothesis, my wife indicated it was interacting with another Anolis when she saw it (you can actually see the tail of the other individual in the pic).”

Flashy Lizards Are More Attractive to Mates and Predators

 A water anole with a colorful dewlap. Image Credit: J. Montemarano.

In the lizard world, flashy colors attract the interest of females looking for mates. But they can make colorful males desirable to other eyes, too — as lunch.

Assistant Research Professor of Biological Sciences Lindsey Swierk is the first author of an article in the journal Evolutionary Ecology on the topic. Called “Intrasexual variability of a conspicuous social signal influences attach rate of lizard models in an experimental test,” the article details an experiment involving clay models of water anoles (Anolis aquaticus), a species of lizard only found in Costa Rica and a small slice of Panama. The researchers conducted the experiment at the Las Cruces Biological Station in Costa Rica, which is one of the Organization for Tropical Studies’ field stations.

To attract females’ notice, male anoles have dewlaps: colorful extendable flaps of skin under their chins. In most species of anole, dewlaps evolved to be as noticeable as possible within the environment, given an environment’s predominant colors and lighting conditions.

“Even so, we see a lot of variation within a species in just how bright dewlaps are,” Swierk said.

While some water anoles have dramatic red-orange flaps, others have more muted colors, more of a dull brownish-red. Researchers wanted to determine the effect these color variations had on their risk of predation.

While it’s widely assumed that flashier males will attract more attention from predators, few studies actually test this assumption. Logistics may be a factor: Researchers have to separate the effects of sexual colors from other aspects of a creature’s body and behavior, a difficult task when using real animals. As a result, many studies show correlation but not causation.

To prove that flashier males face greater risks of being attacked, the researchers created clay models with colored dewlaps — some bright, some more muted. Many visual predators use a stereotyped “search image” to identify prey, so the models only had to approximate anoles’ general size, color and shape. The dewlap color, however, required special attention.

 

“Because different animals have different visual sensitivities than we do as humans, getting the colors right was an important consideration in our model design,” Swierk explained. “We ran some pilot trials before this experiment to make sure our models were convincing as ‘lizards’ — and they certainly seemed to be, as many birds and other lizards took bites out of them!” 

Researchers were able to identity predators from bite marks in the clay models. They included many species of bird, including the strikingly beautiful motmot with its serrated beak. Basilisks and whiptail lizards were also among the likely attackers. The results proved that flashier lizards really do end up as lunch more often.

If bright colors have deadly consequences, why do female anoles prefer them? One answer is that brighter males have either high-quality genetic material or resources that allow them to handle the risk of getting eaten, Swierk explained.

“Because every individual’s evolutionary ‘mission’ in life is to pass on as many copies of its genes as it can, conspicuous traits like these can evolve if they give an individual a high level of reproductive success — even if the flashy trait ends up killing them in the end,” Swierk said.

#DidYouAnole – Anolis maculiventris

Some people think that the anoles with brown colouring and patterns are too drab or boring but honestly I appreciate their ability to blend in almost seamlessly to their habitats. The Blotchbelly Anole is another one of those, usually brown, sometimes with light patterning or a tan line down its back.

The males have a unique burnt sienna coloured dewlap, while the females of this species have no dewlap. Blotchbelly anoles appear to be twig anoles and they inhabit lowland forests in Ecuador and Colombia.

The anole gets its name due to the spotting (but not blotches) on its belly. Female Blotchbelly Anoles may be slightly larger than the males with a recorded length of 124-140 mm (Arteaga 2013), and the males at 120-129 mm.

Reminder: Submit Photos for Anole Photo Contest 2020!

Aryeh Miller and Ansley Petherick

Which anole species will grace the pages of this year’s calendar? Pictured here is Anolis capito. Photograph by Aryeh Miller.

Thanks to all of you that have sent in photos for our calendar contest! For those who haven’t sent anything yet, now’s your chance – the deadline to submit is at the end of THIS WEEK (this Friday, November 13), so if you plan to submit, be sure to do so soon!

To remind you, the rules are here:
Submit your photos (as many as you’d like) as email attachments to anoleannalsphotos@gmail.com. To make sure that your submissions arrive, please send an accompanying email without any attachments to confirm that we’ve received them. Photos must be at least 150 dpi and print to a size of 11 x 17 inches. If you are unsure how to resize your images, the simplest thing to do is to submit the raw image files produced by your digital camera (or if you must, a high quality scan of a printed image).  If you elect to alter your own images, don’t forget that it’s always better to resize than to resample. Images with watermarks or other digital alterations that extend beyond color correction, sharpening and other basic editing will not be accepted. We are not going to deal with formal copyright law and ask only your permission to use your image for the calendar and related content on Anole Annals (more specifically, by submitting your photos, you are agreeing to allow us to use them in the calendar). We, in turn, agree that your images will never be used without attribution and that we will not profit financially from their use (the small amount of royalties we receive are used to purchase calendars for the winners). Please only submit photos you’ve taken yourself, not from other photographers–by submitting photos, you are declaring that you are the photographer and have the authority to allow the photograph to be used in the calendar if it is chosen.

Please provide a short description of the photo that includes: (1) the species name, (2) the location where the photo was taken, and (3) any other relevant information. Be sure to include your full name in your email as well.

Thank you and good luck!

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