Yes, the distichus looked that angry when I caught it!
When I was a kid, my favorite thing to do was go outside with my rainbow zebra-stripe notebook and draw any living thing I could find. Often, especially for the animals, I would include little comments and blurbs about the things I observed them doing, or make up stories about them. As the years went by, I slowly forgot about that book, until I was hired as a research assistant last summer to study anoles in the Dominican Republic with the Frishkoff Lab at UTA.
The week before I was scheduled to leave, I went out and bought a new sketchbook, not knowing if I would actually end up doing anything with it. Luckily, I did, and so I’m here to share a couple of my anole sketches that I did on my trip. While not all the information may be completely accurate, it’s just what I noticed about them while I was drawing and studying them. (Note: For the locations, those are specific to the sites that we were studying while we were there and not the complete ranges).
I hope that you enjoy them, and let me know which ones are your favorites! I think mine are the A. barahonae and A. armouri.
While I unfortunately did not get to actually see an A. eladioi, I still drew one in the hopes that I might.
Over the years, there has been a lot of discussion on Anole Annals about the large, conspicuous dewlap. And rightly so because it is arguably the most evocative feature of the anoles. Much of this discussion has focussed on its function, such as its role in species recognition, mate choice, and territorial communication. But is there a cost to having such an audacious visual signal?
We needn’t isolate this question to just Anolis lizards. All socially communicating animals need to produce a signal that will be obvious to conspecifics. There’s little point producing a mating or aggressive signal if females or rivals never detect it. But there is a cost to being conspicuous and it can be a matter of life and death: the unintended attraction of predators.
Generally, the assumption has been that animals just incur the potential risk of predation for the sake of successful communication. But just how risky is it? The dewlap is often large and brightly coloured, but when it’s not being used in display, you’d never know anoles even had one.
There are also at least two other independent origins of the dewlap, including in the gliding lizards of Southeast Asia, the Draco. In these lizards, the dewlap is again large and often conspicuously coloured.
For both Anolis and Draco, one of the best ways to find lizards in the wild is by the quick flash of colour as males rapidly extend and retract the dewlap during their territorial displays. In fact, it is often the only way to find Draco, which are camouflaged and extremely difficult to spot, even when you happen to be staring right at them.
I had this crazy idea a few of years ago… Would it be possible to build an army of robotic Draco lizards with plasticine bodies that could retain impressions of predator attacks and measure the risk of predation from performing a conspicuous dewlap display?
It really was a ridiculous thought, but my long-time collaborator Indraneil Das was game.
Robotic lizards compared to the real thing in (a) morphology and (b) behaviour (robots were modelled on Draco sumatranus from Borneo).
It was an awful experiment to do. Building the robot army turned out to be the easy bit. To be clear, it took months of development and manufacture, all of which I did in my garage (long story). It then took years to run the experiment, with multiple replications across two continents because the data was puzzling. There were bushfires, floods, battles with swarming wasps and kamikaze leafcutter ants, chipped teeth, falls from ladders, bogged car rentals, hammered thumbs, and in the end I only just managed to get it finished before the world turned side-ways in 2020.
Left: fresh-faced and optimistic in June 2018; Right: brave-faced but really a little shellshocked with the retrieval of robot 2,120 in February 2020 (NB: batteries have a habit of failing and parts started to corrode so only 1,566 robots were fully functional in the experiment).
It turns out that prey that can produce a signal intermittently — effectively turning their conspicuous display on and off at strategic moments, like the dewlap — can drastically reduce their risk of predation. In fact, attack rates by predators on dewlapping robotic lizards were no different to robots that remained unmoving and cryptic in the environment. Which means there doesn’t really seem to be a large cost from increased predation for animals that perform bouts of conspicuous behaviour.
But this wasn’t the biggest surprise.
The experiment included robotic lizards that kept the large, conspicuously coloured dewlap permanently extended so it was always visible. Think of peacocks with their massive tail trains or other animals that are spectacularly ornamented. These features are always visible and are not signals that can be turned on and off. My assumption was that these robotic lizards would be the hardest hit by predators.
This wasn’t the case at all. Predators actually avoided these robotic prey and to such an extent that the probability of attack was lower than the robotic lizards that remained cryptic and didn’t perform any conspicuous behaviour.
Photo montage of predator attacks left in the plasticine body of the robotic lizards
At first, I found this to be confusing and replicated the experiment over and over again. I even called in my partner Katrina Blazek who is a biostatistician to blind the data and independently perform the analyses (Katrina is also a skilled tailor and made all the robot dewlaps). I also dragged in my colleague Tom White who is an expert on animal colour discrimination to confirm that the dewlap really was as conspicuous to predators as I thought it was.
The data was robust.
This type of predator phobia actually helps explain the evolution of a completely different type of animal signal in nature: aposematic signals or warning signals that some prey evolve to explicitly advertise their location to predators to warn them against attack, usually because they’re toxic. Conspicuous poison dart frogs are an obvious example, so are ladybirds (or ladybugs).
The paradox is how these warning signals could evolve in the first place given the first individuals that tried to advertise their warning would be quickly eaten by predators that had no idea the signal was meant to advertise unprofitably until after the attack.
One of the key hypotheses that has been proposed to resolve this evolutionary paradox is that predators are highly conservative in the types of prey they go for. That is, they tend to avoid prey that look unusual in some way, even if those prey are more easily detected.
This is exactly what happened in this experiment. The robotic lizard with the permanently extended dewlap was ‘weird’ and so predators instead targeted the robotic lizards that either displayed intermittently or remained cryptic, both of which were more typical of their familiar prey.
The take home message is:
Follow your ridiculous idea and call on your friends to help.
(But don’t hold metal tools between your teeth. Your dentist will be very annoyed with you.)
New natural history note: “Nocturnal foraging and activity by diurnal lizards: Six species of day gecko (Phelsuma spp.) using the night‐light niche”.
A set of observations, recently published in Austral Ecology, noted six different species of day gecko (Phelsuma spp.) using artificial light at night (ALAN) to engage in nocturnal activity (e.g., foraging, courtship, and agonistic behavior). Lizards of this genus are widely believed to be primarily diurnal, however, their propensity to colonize both urban and highly-modified habitats, as well as establish invasive populations within novel landscapes, suggests they are a taxon that is quite flexible and adaptable.
A blue‐tailed day gecko, Phelsuma cepediana, foraging for insects under a fluorescent light in Mauritius. Photo credit J. L. Riley.
Remind you of any other small- to medium-sized adaptable and diverse group of lizards?
Keen readers of the Anole Annals will recall several posts about the effect ALAN can have on anoles, including its impact on physiological stress, metabolism, invasive potential, and reproductive output. With many accounts noting the costs and benefits of shifting diel cycles and daily activity period, but also the general impact light pollution may have. No doubt, there remains a lot of research potential to examine similar questions for the many Phelsuma species across their native and invasive ranges.
Reunion ornate day geckos, Phelsuma inexpectata, engaging in nocturnal activity under a fluorescent light inside a bathroom in Manapany-Les-Bains, Reunion (A,B), including courtship behavior (C). Photos credits C. Baider and F.B.V. Florens.
It is always worth keeping your eyes peeled in the field.
The observations that led to this note came from nine researchers working in various sites, locations, and projects across a number of archipelagos spanning the Indian Ocean and over several years. As with many natural history observations, most of these accounts began with a researcher – who was no doubt occupied with an entirely different task – seeing something out of the ordinary, snapping a picture and jotting down some quick details, and carrying on with their work. A great reminder to never leave home without your trusty notebook; digital or otherwise. Then later on, sometimes much later, this information regarding “something weird you saw” is shared between colleagues, sometimes met with an “oh ya, I saw that too, different species, different location, but the same thing,” and from there, patterns emerge and collaborations bear fruit.
Over the years, Anoles Annals has featured a number of posts related to day geckos, with some keener anolologists expressing the feeling that these colorful, charismatic, and adaptable geckos could be seen as “honorary anoles.” A compliment, surely, the geckos would appreciate and reciprocate toward anoles, if given the chance. Despite their stunning appearance, long history of public awareness, and ability to sell car insurance, there remains a lot of information we do not know about day gecko behavior, biology, and ecology. We hope this natural history note will prompt further research interest into this enigmatic group of lizards.
Upon returning to the first address, I had to search for a long time, 20-30 minutes, before finally stumbling upon one adult male A. Allisoni relaxing on the top of a fence.
I only managed to snap one picture of it in this pose before it hopped onto a palm tree on the other side of the fence. As it slowly made its way up the tree, while cautiously keeping an eye on me, I snapped a few more photos.
After this, I moved on to the next address, about 15 minutes further south in Naples. The area to search was very small, but there were several dense bushes to sift through. After a half-hour spent combing the bushes and peering into the greenery, I finally spotted another adult male A. Allisoni in the underbrush, close to the ground. Unfortunately, he was so deep in the bushes that there was no way to get a clear photo. After an extensive chase, where I scratched myself all over with pointy branches as I tried pursuing the elusive anole through the bushes, he eventually disappeared.
Defeated, I looked up and spotted a small, likely female, A. allisoni hopping from twig to twig much higher in the trees above. This one also completely disappeared as I went to take a picture, unfortunately. However, just as I was about to give up hope and leave, I spotted one final small anole climbing the trunk of a nearby tree at hip level. I crept over and quickly wrapped my arms around the tree where I last saw the anole, and, sure enough, safely snagged it!
Again, at first glance, it appears to be a green anole. But look at the ear cavity. In this observation of a male A. allisoni, the ear cavity is also more of a gash, instead of a hole. And the large scales on the snout would also imply A. allisoni. What do you think?
Join me on Instagram @dailyanole to follow my adventures!
Driven by my quest to find Allison’s anoles (A. Allisoni) in the wild, a few weeks ago I dove into a pit of research papers to look for known sightings and/or colonies of A. Allisoni in Florida. I came upon a few vague notations of a colony in Naples with an address included. So, as part of a herping trip for various anoles and lizards to Miami last week, I stopped in Naples along the way.
I drove to the address and, after parking and entering the area, the first thing I saw was a large male specimen of A. Allisoni perched on the side of a palm tree. Shocked and delighted, I snapped a picture.
To see such a beautiful species of anole in Florida in the wild was breathtaking.
The male allisoni was perched on the palm tree with one large male A. sagrei (brown anole) below him. As I approached the palm to get a clearer picture, the sagrei leaped off the palm onto a smaller scrub, and the allisoni followed right after. The two briefly scuffled, nipping at each other before both went their separate ways and I did not see them again.
Strolling around the area to search for more, I found a very small green juvenile anole. It appeared to be allisoni, but did not give me enough time to properly examine it before scuttling up a tree and into the canopy.
Upon returning to the same spot where the first allisoni was, there was another just a few feet away that I had somehow missed the first time. This one had no hints of blue on its head, but simply from its large size, I took a guess that it was an allisoni. After succeeding at capturing it, I took a picture:
Upon first glance, it seemed to be A. carolinensis. However, on a closer look, both the shape of the ear hole and the large scales on the snout suggested allisoni. Here’s a picture of A. carolinensis for comparison:
For the genetics experts reading this, is there evidence of allisoni interbreeding with carolinensis?
Upon revisiting the address the next day, I searched in the same place I found the first allisoni, and, sure enough, found another one, this time suspected to be a female.
Again, I notice the oddly-shaped ear holes and eyes that seem too large for the head, more characteristic of allisoni than carolinensis.
In total, at this colony, I observed four possible A. allisoni, including two adult males, one adult female, and one juvenile.
I plan to return to check for more allisoni before the warm weather ends and anole activity decreases for the winter.
The following was written by Keeley Peek and Alyssa Vanerelli, two research students in the Reynolds Lab at The University of North Carolina Asheville. Here they document some experiences with a lesser-known anole species- Anolis scriptus– a species our research group has tried to acquaint AA readers with previously (1,2,3,4).
As aspiring tropical herpetologists, adventures aren’t hard to come by. A combination of traveling to new places and the thrill of encountering new species is a constant excitement. From high in the Blue Ridge Mountains, we heard the soft call of crystal blue waters crashing against a distant shore, and importantly, the scurry of little legs across the sand. It was time for an adventure to the Turks and Caicos Islands.
We touched down in a small plane on the long runway of remote Big Ambergris Cay, one of the last strongholds of the Turks Island Boa (Chilabothrus chrysogaster) and Turks and Caicos Rock Iguana (Cyclura carinata). While these two species seem to rule the island during the night and day, respectively, they are not the only ones that think they own the place. Within a mere moment of tumbling out of the 5-seater plane we spotted our target. The Turks and Caicos Anole (Anolis scriptus scriptus) was soon found to dash under every rock, prickly plant, and structure around. We know surprisingly little about these amazing anoles, which are widely distributed in the southern Lucayan Archipelago. Few focused studies on the natural history of this species have been conducted, and each time our Lab visits this region for our ongoing research on boas and iguanas, we often spot Dr. Reynolds imploring us to find a way to fold in some time for anole study.
Female A. scriptus, hidden among the vegetation.
Although our main efforts were on collaborative boa and iguana research with the San Diego Zoo Institute for Conservation Research, most days we would spend our free time in the afternoons in the hot sunlight trying to catch as many anoles as possible. Without any nooses, nets, or know-how, this was not the easiest task. Around the compound where we stayed, the anoles could be found basking in the sun on the concrete building walls or other human structures, reminding us of work done by Kristin Winchell of Washington University in St. Louis (who gave a seminar at UNC Asheville). They also taunted us from tree branches, just out of our reach. The males on Ambergris Cay stood out with a striking yellow underside, yellow extremities, and an orange-yellow dewlap contrasting remarkably with the beige covered their backs. Females sported a less-colorful look, but have a curious pattern consisting of a light stripe running down their back crossed by thin black bars. We were also able to observe, and sometimes catch, anoles as we worked in the evenings catching boas.
After spotting a beautiful male A. scriptus on what may have been a water heater (we weren’t exactly focused on the structure), we silently stalked towards our scaly tailed friend. After discussing the best angles, timing, and speed we should use to capture this anole, we froze ready to strike. One of us raised a hand for distraction, the other sneaking up in the blind spot to… watch as the anole disappear over the side of the heater. We retreated with a stinging defeat, only to return later as the anole had returned to his basking spot. With a few recalculations and adjustments, we crept in for round two, and emerged victorious.
An amazing feature common among all anoles are their dewlaps which they use to attract females and discourage predators as well as other males. Adorned in vibrant colors, the dewlap is a feature that is easiest to observe when a specimen is in-hand. As newcomers to catching A. scriptus, it was a bit of an adjustment to learn to delicately handle these tiny but surprisingly strong creatures. We received some advice from a seasoned A. scriptus catcher (who doubles as our research advisor), Dr. Graham Reynolds, that the best trick is to let them bite us on the finger and then they will gently extend the dewlap. At first, we believed he was pulling our dewlap, and then we realized he was extremely serious. With a quick game of rock-paper-scissors to determine the anole’s victim, we let the creature’s teeth sink a whole nanometer into our skin and extended its sunrise-colored jewel of a dewlap. We embraced the pain and received the reward of observing one of the anole’s best features. Count us among two of the newest fans of the incredible Anolis scriptus.
Learning a new technique.
p.s. Anolis scriptus is going big-time, having featured in recent publications inNature and PNAS. We look forward to the time when they are as popular as A. sagrei!
The Reynolds Lab (www.CaribbeanBoas.org) studies the ecology and evolution of reptiles and amphibians in the Caribbean and the southeastern United States. We are an undergraduate research-centric Lab.
Predation event between a Praying Mantis (Mantodea: sp.) and a sub-adult female of Anolis cusuco. Photo Credit – George Lonsdale
A natural history note published September 2019 in the journal SAURIA details an unusual observation of anolivory by a Praying Mantis. Specifically, it discusses an event involving the predation of a sub-adult female Anolis (Norops) cusuco.
Anolis cusuco owes its name to its type locality in the cloud-forest of Cusuco National Park, Honduras, and is a species endemic to the country. Few publications exist regarding the natural history of this species and much regarding its ecology, including its potential predators, remain unknown. While a small contribution, this observation describes the first, albeit somewhat unsuspecting predator for Anolis cusuco.
An adult male Anolis amplisquamosus with black gorgetal scales immediately after capture (left); the same individual ~10 min later with white gorgetal scales. Photo Credit – John David Curlis
Anole dewlaps are excellent examples of a “complex signalling system.” They exhibit a staggering diversity of colours and patterns. Each dewlap is species specific and adapted to enable these lizards to communicate, attract mates and guard their territories from rivals or competitors. Generally, the colour of a dewlap (and its gorgetal scales) is considered an unchangeable descriptive trait. This colouration is not only relied upon by scientists looking to identify a species, but also by anoles that co-occur and partition with different species in their select niche.
Therefore, it might be surprising to learn that recent observations prove rapid colour change in anole gorgetal scales is possible. The question is, what implications does this have?
A recent publication in IRCF Reptiles & Amphibians details an observation of Anolis amplisquamosus whereby a male individual upon capture possessed black gorgetal scales that quickly changed to pale yellow. Upon consulting the literature, it seems only one prior documentation of colour change in gorgetal scales was reported (Leenders and Watkins-Colwell, 2003), coincidentally also involving a member of the same species clade.
This recent observation of chromatophoric regulation in anole gorgetal scales may be significant in the wider context of anole biology, in confirming photographically that coloration is not always a fixed descriptive or diagnostic feature — at least among members of the A. crassulus species group. Accordingly, this information suggests that some anoles may have the ability to regulate the colour of their gorgetal scales in the same manner as they regulate dorsal and lateral scale colour.
Because the colour of gorgetal scales is a character often used in species identification, understanding the mechanics and the purpose of such a change is crucial; as well as any implications to display behaviour, communication and anole interactions.
Adult water anole (Anolis aquaticus) from Coto Brus, Costa Rica, with an exhaled – and recycled – air bubble. Photo by Lindsey Swierk.
Over the past few years, I’ve been accumulating evidence that the water anole (Anolis aquaticus) might be a tiny scuba diver in the streams of its home in southern Costa Rica. Anolis aquaticus takes to the water as refuge from predators, swimming and often diving underwater for long periods of time – the record at my study site is currently 16 minutes! To enable these crazy-long dives, it’s possible that anoles may have come up with a scuba-tank method of sorts to “breathe” underwater. I’ve compiled a video of what appears to be underwater respiration of a recycled air bubble that clings to the anole’s head. (A few more details about these observations will be in the upcoming March issue of Herpetological Review.) For now, enjoy the video!
Satellite imagery of when the lights went out in the brightest region of the Caribbean.
You have probably heard about the hurricane’s effect on humans: months of ensuing darkness, destroyed roads, houses leveled and roofs torn clean off, no fresh water, and significantly crippled infrastructure and public services leading to over 1,000 lives lost when it all was over.
I’ve been back to the island now twice since the hurricane, once in January of 2018 and once last week (November 2018).
Four months post-hurricane
The destruction to both urban and forest areas was jaw-dropping when I visited in January to help Kevin Aviles-Rodriguez (UMass Boston) launch a project on urban lizard recovery and natural selection following hurricanes. (Side note – this research has yielded some really intriguing results so far and I look forward to Kevin sharing those with us here at Anole Annals in the future!) On that trip, four months after the hurricane, I found the island in disrepair. Many people still had no power or clean water, stoplights and electrical lines dangled from their snapped poles island-wide, roofs were covered in blue tarps, and driving involved dodging car-eating potholes, downed power lines, and debris. Most stores and restaurants were closed and many roads were impassable.
A stand of trees on the west coast four months post-hurricane (near Rincón).
The trees left standing in urban areas were bare toothpicks. I’m told that immediately following the hurricane, the leaves looked like green snow coating the ground several inches thick. Most of the trees that survived were the large and common urban species: mango, flamboyán, ceiba–leafless but still rooted. When we visited the forests I was equally shocked by the destruction: trees looked as if someone clipped them all off clean around 15 feet up, the canopy was gone and all of the large trees like Cecropia and Cocoloba were downed. Lianas had taken over giving the forests a bushy, surreal appearance. I left the island that January wondering how long it would take to recover; the human side and nature side alike had a long road ahead of them.
What was once closed-canopy secondary forest on the north coast (near Arecibo).
Fourteen months post-hurricane
When I returned last week, now 14 months post-hurricane, I was pleasantly surprised to see the island was recovering. Roads had been repaired, power had been restored, stoplights were working, debris had been cleared, restaurants and stores were open, and houses rebuilt. From the human side of things, the island seemed to be recovering. On the west side of the island, the leaves of the large trees had returned. Forested areas had more dense understory than typical and the canopy was still fairly open, but overall it seemed like the forests and urban areas were both returning to normalcy. I found many urban lizards without a problem, including Anolis cristatellus, A. pulchellus, A. stratulus, Ameiva exsul and the non-native green iguana. I was surprised however, that the nights were eerily quiet. The familiar ear piercing chorus of coqui was reduced to intermittent calls of only a few individuals. The coqui don’t seem to have recovered quite as well as the anoles.
No trees? This urban A. cristatellus seems okay with that.
Anolis cristatellus
Anolis pulchellus
Many challenges certainly still face the residents of the island, but it was starting to look more like the Puerto Rico I knew. So it was quite a shock when I visited the newly re-opened El Yunque National Park. El Yunque was hit particularly hard by the hurricane as the first landfall was just south of the forest near Yabucoa. Strong bands of wind pummeled the area, leading to massive landslides that closed the rainforest for months. The national park website said that only La Coca falls and Yokahu Tower were open to visitors, but I found a park ranger who informed me that the Mt. Britton trail was open (and the road to the peak of El Yunque had been cleared as well, though not the cloud forest trail).
As I drove up the mountainside to the Mt. Britton trailhead I was shocked at how open the forest was. When we arrived at the trailhead, my jaw dropped. The canopy had not recovered at all. The palms seemed to be the only trees that survived. I’ve hiked this trail many times, but this was the first time I did not wear a long-sleeve shirt – it was hot and dry. Perhaps the lack of animals shouldn’t have come as a surprise then. I didn’t hear a single coqui call while hiking the trail, where in the past we would hear many different species along the route. I also did not see a single Anolis gundlachi, where before my favorite trick was to tell someone that I could make lizards appear on demand then reach out and snatch one off a tree – they were that common! I did see a handful of Anolis evermanni, but only a few. Below are a couple of before and after photos of the same portions of the trail.
Mt. Britton trail in January 2017
Mt. Britton trail now, 14 months post hurricane
The entrance to the Mt. Britton trail before the hurricane…
and the same location 14 months after the hurricane
The impacts of hurricanes on wildlife
Recent research has shown that the insect populations of El Yunque have been declining for years, and certainly hurricane Maria did not help this situation. Perhaps the anole and coqui populations have suffered because of a collapse of food resources? Or perhaps the microclimatic shifts were too much for the lizards to handle? Anolis gundlachi does have a strong affinity for cool and moist habitats and it seems quite likely that with the current state of El Yunque, very little suitable climatic habitat exists for this species. Or perhaps the hurricane itself reduced the anole populations. Recent research on Anolis scriptus found that hurricanes can pose strong selective pressures leading to phenotypic change. Whatever the reason for the apparent decline, I am eager to check back in with the lizards in a few months when I visit again and even more eager to hear about the research of those studying herpetofaunal hurricane recovery.
No A. gundlachi to be found at El Yunque 14 months after the hurricane, but quite a few A. evermanni like the one seen here.
Are you studying the effects of hurricanes on lizards? Are you studying the recovery of Puerto Rican herpetofauna after Maria? We would love to hear more about it! Let us know in the comments, or consider contributing a blog post to Anole Annals.
I hope that you enjoy them, and let me know which ones are your favorites! I think mine are the A. barahonae and A. armouri.
