Author: Jonathan Losos Page 9 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.

Trinidadians Reflect on Their Lizards

Anolis aeneus. Photo by shanelkalicharan.

Vaneisa Baksh is an editor, writer and cricket historian for the Trinidad Saturday Express. She’s written two essays on the local lizards and along the way has chided up herpetologists for not responding to the first one. Let’s get to work!

First she writes several weeks ago, in an article entitled “The LIzards Running Up and Down”:

The first time I heard the sound, I thought a bird had flown into the house, although none of my regular feathered folk chirped like that. I searched and searched, remembering how one time a little dove had come in and had been frantically trying to escape while I tried to guide it to the open window in the kitchen. My efforts were just increasing its anxiety and I had to leave it alone to simmer down until it mercifully found its way to freedom.

This time, there was no bird and eventually, as the sound repeated itself, I spotted the culprit. It was a lizard, a gecko, and although we have co-habited in different houses since I was a child, I’d never heard one of the buggers speak. That was a couple years ago, and curious to know if this was a mutation of the creature we called “24-hours” on account of the myth that if it fell on you, it would stay there for an entire day, I went looking for information.

It turned out that these are really house-loving critters. They prefer to be indoors and are harmless, and might even be regarded as useful. I learned that they feed on insects, cockroaches, termites, wasps, flies, spiders, moths and poor butterflies. I’d decided that I would just have to get used to the unusual sound—the most apt description on Wikipedia was “tchak tchak tchak”, which it said was often sounded six to nine times in sequence. I have a way of seeing words in shapes, and maybe sounds as well. Every time I hear the gecko chirp, I would see the sound like a fairly squared-off pellet. Perhaps it is because the sounds are evenly pitched and last for roughly the same length of time. I don’t know, but I have tried to get used to it suddenly rapping into my consciousness.

At first, it was restricted to my bedroom and my study, but now it seems the lizards are everywhere. Whereas I found it an occasional interruption, now I feel there are colonies of them living in my house and even though I hardly see more than one at a time, I feel that they have taken over.

It is one thing to adjust to the sound they make—tchak tchak tchak is far more bearable than the abrasively loud grinding from the welding next door—but these discreet urban dwellers leave their little droppings everywhere. Everywhere. Not only do I have to clean them off the floors, especially at the base of the walls, but the area that really trips me is by my bedside table and on my bed. Yesterday, I washed my sheets and replaced them. As I prepared to turn in last night, I spotted the droppings on the edge of the bed. I suppose that’s why I am bringing them up now.

I would dearly like to know if other householders are experiencing this increased presence that is now forcing a whole different level of housekeeping. I have been getting faint whiffs of urine as well, and it drives me crazy, because I am washing cushion covers, curtains, sheets, everything that could be contaminated, and mopping the floors far too often.

It’s not just being finicky, which I am, but for some time now, my eyes have been unusually sensitive and gritty. While it is true that I am spending a considerable amount of time reading and writing in front of various screens, and that the presence of Saharan dust has been exacerbating things, my ophthalmologist says there is evidence of some kind of persistent irritant, or allergy affecting my eyes.

Naturally, I am mindful that it is possible that the creatures overhead who seem to like my bedroom might be doing numbers over my bed and that might be messing with my eyes. I am not trying to gross anyone out, it just seems that it is likely that there is a growing population of the lizards, which I think we also call woodslaves, and that while we might be adjusting to their presence and their noises, we might not be aware of the side effects.

I’ve never had a problem with lizards. When we were children, the whole brood of about 15 to 20 cousins on any given night would gather in my grandfather’s living room to look at television shows because nobody else had a TV.

We’d start streaming in when the news programme, Panorama, began at seven o’clock. That was when he would turn on the black and white beauty with the wooden cabinetry. Afterwards when some other show began (the real reason we were there), he would sit there with us, and if there was any sign of anything remotely inappropriate for us, like a kissing scene, he would suddenly exclaim, “Look, look, look, the lizard up there!” Naturally, we would all momentarily turn our heads away from the screen at the unexpected shout. Sometimes there was a lizard, but more often not, and he would say, “Ah, he run away!” But his distraction worked well enough, or so he thought.

Harmless enough.

But I feel something has changed. There are more, they are loud and though they love being indoors, they are not house-trained! This might sound creepy though I say it in jest, what if I am now the interloper in the house of the lizards?

—Vaneisa Baksh is an editor, writer and cricket historian.

E-mail: vaneisabaksh@gmail.com

 

And then Vanessa writes yesterday in “Welcome to the Lounge of Lizards”:

I’D hoped that bringing up the ungovernable appearance of house lizards might have elicited a response from a couple of herpetologists. Disappointingly none came; but many people shared their experiences and theories. There was much to learn from these personal stories, and they broadened my sense of community, so I want to share some titbits from a few.

I mean, here we are, locked down in our separate cubicles, not knowing anything about one another, and suddenly, we are sharing lizard tales, revealing snippets of our lives that tell us something about daily trials we have in common. It’s not something we’d chat about, and noticing that our traditionally unobtrusive house mates have become loquacious would hardly qualify as a subject for conversation—unless you have physical visitors and the lizards are contributing their five cents to the discussions. Innocuous things have to force themselves unto your radar—usually by causing some disruption—before they register on your consciousness. Like the jiggly latch on a window that you notice every time you open or close it, but never outside that moment.

Curious if these chirpy critters were mutants or had just been imported, I read of work done by Jonathan Losos, a professor of evolutionary biology and a herpetologist, whose research is mostly concerned with how lizards interact with their environment and how they have diversified. Apparently they have focused on the “evolutionary radiation” of Caribbean Anolis lizards, among others, but they are also looking at how species are adapting to urban environments.

One related study examined the impact of an invasive anole species in Dominica. Up until two decades ago, it was home to a single species until a second species arrived tucked inside a shipment of lumber. Not hard to imagine our lizards coming in by sea. I remember landing in Nevis on one of those small aircraft and as we disembarked, a scorpion scurried down the aisle as soon as the door was opened. Naturally, ­passengers let the hustler disembark first.

A 65-year-old reader sent this: “Our first house was a small ‘board-house’ with a thatched roof and termite-ridden boards. I could knock on a board to find out if it was termite-eaten by the hollow sound that emanated. Prying into the thin cover, I would find the hollow cavities. Here the house-geckos laid their eggs. Unfortunately, sometimes I would remove the eggs. The old Indian people used to call them ‘bistooyas’, the ones about three inches long, sometimes with white stripes from their eyebrows to the body.”

Quite a few people said they had been hearing the noises but couldn’t figure out the source, assuming it was some kind of night bird, and some thought they were alone in this experience.

One person said that around the same time they began hearing those sounds they noticed that “my eyes felt like I had nits in the base of my eyelashes, and the attendant discomfort… At the same time, I had noticed a reduction in small spiders, spider’s webs, and mosquitoes”.

A woman of the West included a delightful description of the upsurge of geckos. “There’s quite a lot of courtship going on between pairs, appropriately, in our bedroom, and each pair seems to play tag, with a pursuer and its quarry. Inevitably, though, they come to an agreement and tiny baby lizards pop up soon after.” She doesn’t mind them, she says, but most of the women harbour strong feelings.

“I detest those creatures. They are annoying. They feed on the insects in the house. If by chance I should see one within easy reach, I implore my husband to get rid of it, and he would hold it using a piece of cloth and throw it outside. He doesn’t harm them,” said one.

A few mentioned that peppermint infused with water makes a reasonable repellent. One had specific directions: peppermint oil may be used by soaking cotton balls and placing them on the top of shelves, inside closets, behind books and similar places. I prefer using a spray bottle, measuring half water and quarter oil and spraying in the same places. It’s been keeping them away so far and the smell becomes less pungent after a few days.” Another said she had tried it, but is worried about the larger implications.

“There is something amiss in the ecosystem. This, what can only be described as an infestation, is a new phenomenon. Is this a new and invasive species or has this lizard been blessed by depleting stock of its natural predators? I do think it is something which the scientists need to investigate. Is there something more sinister at work? And what are the implications? I have always been leery of lizards. Their presence disconcerts me. And now this is like living in some kind of mild horror story—in my own house! Lizards pop up everywhere—in the vegetable basket, in the clean-clothes basket, drop from the roof. One found its way into my glass of water; fortunately, I looked down before I sipped!”

Another said, “I agree with you totally on all that you said, and I believe that these creatures are being used for sinister purposes.”

I don’t know about that, but I enjoyed learning more, like discovering that a group of lizards is called a lounge. I imagine them lounging about our homes and I figure what better place for a lizard to lime than this country!

Whit Gibbons on Why Anoles Change Colors

From the Tuscaloosa News:

A male green anole flashes its dewlap in a territorial display. Males flaunt the red throat fan to challenge other males. [Photo by Tom Jenssen]

One of the most commonly seen lizards in the Southern states is the green anole, also known as North American green anole or Carolina anole. (Its scientific name is Anolis carolinensis.) Although more than 400 species of anoles are known to science, the green anole is the only one native to the United States. Most people appreciate seeing them in their yards.

Q. A type of lizard we have in Birmingham, Alabama, is sometimes green and sometimes brown. I know it is not two different kinds of lizard because I have watched one change from brown to green. Are these a type of chameleon that can change skin color to match their surroundings?

A. No. Anoles are in a different family of lizards from Old World chameleons. Those are the ones famous for being able to change skin color based on the background, thus creating a true camouflage. In green anoles, color change is a response to external factors, such as temperature and humidity. It may also be influenced by hormonal changes. Whether lizards experience emotions comparable to humans remains a mystery. Researchers continue to investigate why anoles change color, as well as what purpose that change serves for the individual lizard. Most anoles found hidden under bark or leaves on cool days will be brown. If you pick up a brown one and hold it, it will usually turn green.

To learn more, I contacted Tom Jenssen, an expert on the subject of color-changing behavior in green anoles. During his career as a professor at Virginia Tech, Jenssen observed thousands of green anoles while conducting research on the species.

His observations confirmed categorically that the color of a green anole has nothing to do with what the lizard is standing on. One on a green leaf can be brown; one on dark soil can be green. He indicated that factors causing a green anole to exhibit the brown color phase are not completely understood, but he explained the biological mechanism:  “Color-shifting comes from melanophore activity over a sub-dermal layer whose structure reflects green wave lengths.”

In other words, the concentration of black or brown pigment cells determines the color exhibited. If the pigment cells are large, they obscure a lower level in the skin that reflects green light. When the cells are concentrated, the lizard looks dark brown, mottled brown or even like a bad bruise of blotchy brown and olive-green. If the pigment cells contract in size, the lower level is exposed, and the lizard appears green.

He further noted that the activity of pigment cells and their concentration are controlled by the endocrine system, the glands that affect hormones and mood changes for many animals.

The remaining biological mystery: What triggers the endocrine system to cause the pigment cells to contract or expand? Body color in anoles is highly complex with no simple answer for why an individual is a particular color at any given time. Social interactions with other lizards may be responsible in some cases. Brown coloration could possibly result in faster warming of the body on a cool sunny day.

Q. Why do these lizards that can change from brown to green sometimes have a bright red throat?

A. Male green anoles use the vivid red throat fan, or dewlap, to challenge other male anoles and sometimes even other animals. The dewlap display is often accompanied by push-ups and head-bobbing. An invasive species from Cuba, the brown anole, now found in Florida, Georgia and Alabama, has an orange dewlap. Next time you see a green anole displaying a red throat, take a moment to watch its performance. Who is its audience? Is it another anole in the vicinity — or is it you?

Native green anoles are completely harmless and offer fun outdoor entertainment. Enjoy watching them stalk bugs and interact with each other. They are indicative of a healthy environment and deserve our appreciation wherever we find them.

Whit Gibbons is professor of zoology and senior biologist at the University of Georgia’s Savannah River Ecology Laboratory. If you have an environmental question or comment, e-mail ecoviews@srel.edu.

Whit Gibbons

Ever Seen an Anole Drink?

Charles Leeper shows us a green anole in action from around his home. And here’s an oldie of Anolis smaragdinus doing the same:

 

The Ol’ Dine-and-Dash, Anole-Style

 

Or should we call it dine-dash-and-dewlap? Anole video-chronicler Charles Leeper has provided another view of green anole life around his house. He describes it thusly: I recently captured some anole footage that you might find interesting. In the video, we see the anole repeatedly extending its dewlap after catching the insect. I know dewlap extension is for displaying to a mate and establishing territory, but could it also be a show of triumph or excitement. I ask because there don’t appear to be any other males in sight, and the anole does it immediately after catching the prey.

Is It Curtains for the World’s Most Famous TV Anole?

Harry, the lizard, clearly a Lesser Antillean anole from the fictitious island of Saint Marie near Martinique and Guadeloupe in the British detective series Death in Paradise, is in jeopardy. Read all about it, but beware of spoilers.

More Anoles on Postage Stamps

Over the years, Anole Annals has featured several posts on the appearance of anoles on postage stamps from countries around the world (e.g., 1, 2, 3), mostly thanks to Uwe Bartelt. Now AA stalwart George Gorman has taken up the mantle.

In reference to the stamps above, George writes:

“Djibouti, on the Horn of Africa somehow must have learned from P.T. Barnum that there’s a sucker born every minute. As a collector of anoles on postage stamps , I couldn’t  refrain from purchasing this recent issue that featured two very classy anoles: Anolis gorgonae and A. proboscis (male and female). I would bet there aren’t five people in Djibouti who have ever heard of these species, let alone who worry that they are endangered.”

And with regard to the famous iguana ecomorph (below), George writes: “I had enough trouble dealing with Dactyloa and “Norops” and the like… but this is getting out of hand. This mini-stamp- sheet from Nevis .. (ok.. it is labeled “reptiles of the Caribbean”)  identifies the creature as…Anegada Ground Iguana, Cyclura pinguis!”

Finally, I can’t keep from reprising a post of mine from nine years ago, in which I point out that one of my photographs was used without permission on a postage stamp. Anyone know a good anole intellectual property attorney?

 

Texas Nature Center Video on Green and Brown Anoles

This prototype video from a nature center in Bellaire, Texas has a degree of charm and entertainment, but a few factual errors and some unexpected historical/geopolitical statements. Still, it’s nice to see anoles chosen as the subject of their first video in what could be a series of micro-documentaries. More on the video and anoles at this website.

True Facts about Anoles

No, Ze Frank hasn’t created a True Facts about Anoles video–though surely that’s in the works (check out his list of videos). But he does have a very good one on camouflage and mimicry, and anoles make numerous appearances. For the record, my favorite True Facts is the one on chameleons.

Taiwan Tries a New Tack to Get Rid of Invasive Festive Anoles

From the pages of the Taiwan News. We’ve had posts on the invasion of festive anoles into Taiwan previously.

Facing invasive lizard dilemma, Taiwan tries a different tack

Brown anole has caused eco-havoc in Taiwan, but a research team in Chiayi may have the answer 

A brown anole displaying. (Wikipedia, Creative Commons photo)

A brown anole displaying. (Wikipedia, Creative Commons photo)

The brown anole (Anolis sagrei), an invasive lizard species native to Cuba and the Bahamas, has been causing damage to Taiwan’s ecosystems for years, but solutions to controlling its spread have been elusive.

Now a university research team in Chiayi County is trying a different approach — working with plant nurseries in parts of the county to get rid of anole eggs from plant soil — that appears to be promising. Chiayi County was the entry point for the non-native species and has been at the epicenter of its proliferation for nearly two decades.

During that time, the county government has tried to grapple with the problem because of the serious threat posed by the lizard to Chiayi’s biodiversity, said Chen Hsun-wen (陳宣汶), an assistant professor in National Chiayi University’s Biological Resources Department. From 2009 to 2017, local authorities focused their eradication campaign on offering financial incentives to the public for getting rid of the lizards, a system that spurred increased interest in catching brown anoles and controlling their population.

Eventually, however, the county discovered that the more than NT$10 million (US$356,951) in cash rewards handed out through the incentive program did not translate into control of the brown anole population, according to Chen. It may even have been counterproductive, he said, because it caused problems in compiling accurate statistics and resulted in inefficiencies in getting rid of the lizards.

Reptile reputation

That led the Forestry Bureau’s Chiayi Forest District Office to consider a new approach — outsourcing a brown anole prevention and control project to a research team in Chen’s department in 2018. The team adopted a strategy of containing the reptiles instead of slaughtering them and put in place measures to confine them to areas where they already existed to keep them from spreading.

The team’s primary target has been plant nurseries, a common sight in Chiayi, after it found that brown anoles were most likely to spread to different areas through the movement of seedlings and saplings shipped by those nurseries, said Hsu Wei-chieh (徐偉傑), an assistant research fellow in the department.

According to Hsu, the lizards usually lay their eggs in the soil of nursery plants and hide in the branches and leaves of saplings, and the containment plan is aimed at getting nurseries to check for the lizards or their eggs when a batch of seedlings or saplings are shipped out.

Floridians

To assist the nurseries in the effort, the team has dispatched workers to monitor the nurseries and help them check for lizards or their eggs and get rid of them before products are shipped, Chen said.
Because of the difficulty in spotting the lizards or their eggs, the team also sets traps at the nurseries to catch the reptiles.

Chen said gauging the population of the brown anoles is not easy, but it appears that the team’s efforts are having some impact, as the population of lizards in Shuishang Township in Chiayi County, while still high, appears to be growing at a much slower rate than previously. Shuishang Township has several nurseries where many varieties of tree saplings imported from the U.S. grow, and it is where the lizard species was first found in Taiwan.

A genetic analysis found that Taiwan’s brown anoles came from Florida, Chen said, and he believes they came through imports of plants and plant products from Florida that had the eggs of brown anoles in their soil.

The team is now hoping that through their focus on controlling the brown anole population at their source, the species can be contained and be stopped from damaging Taiwan’s ecosystems.

How Well Can Anoles Perceive the Patterns on Anole Dewlaps?

From the pages of Chipojo Lab:

“Manuel recently published a paper in the Journal of Herpetology with Leo Fleishman and Maya Prebish, examining visual acuity and perception of Anolis dewlap patterns. Yesterday, a news feature came out about the article in El Nuevo Día, sharing the findings en español. Keep scrolling below for an English translation!”

Read the entire, extremely interesting post here!

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