Professor and Curator of Herpetology at the Museum of Comparative Zoology at Harvard University. 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.
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City living comes with unique challenges. If you’re a lizard, scaling a windowpane without sliding off is one of them. One lizard has already evolved traits to help it do just that.
“Urban areas are just another environment. The animals that live there aren’t somehow immune to natural selection,” says Kristin Winchell of the University of Massachusetts Boston.
Her team compared males of the anole lizard (Anolis cristatellus) in the Puerto Rican cities of Mayagüez, Ponce and San Juan with those in nearby forests.
They found that city lizards regularly clung to objects like walls and windows, proving that they use the full urban environment instead of restricting themselves to wild patches more similar to their forest roots.
Compared with forest-dwellers, city lizards had longer limbs and more lamellae – scale-like structures that help their toes stick to surfaces. These traits probably enable them to stay attached to slippery urban perches. “I chased a lizard that ran straight up a window 30 feet and was out of reach in 15 seconds,” says Winchell. “I couldn’t catch this well-adapted lizard.”
The team also raised urban and forest lizards from the Mayagüez region in the lab and found that differences in limb length and scale number remained, suggesting a genetic basis to the urban lizards’ abilities.
But well-studied examples are rare. “Urban evolution is a really young field,” says Winchell.
Evolutionary biologist Jason Munshi-South of Fordham University in New York agrees. “There aren’t many documented cases of urban evolution yet, but people are going to start looking for them in earnest,” he says.
Munshi-South believes Winchell’s study is an excellent addition to this emerging field. “The next step,” he says, “which I’m excited to see them do, is to identify the genes underlying these adaptive traits.”
Winchell says that, ultimately, understanding urban adaption could help conservation. “Having a grasp on which animals tolerate urbanisation gives us a better idea of which ones we need to focus on when preserving natural habitats,” she says.
The Dodo provides the full details, but here’s the gist: “I was at the zoo watching the gorilla exhibit [at the San Diego Zoo], and that little lizard came up and just froze when the gorilla started playing with it. He picked it up by the tail a few times, poked at it, but never killed it.”
As Yoel Stuart reported previously in AA‘s pages, Anolis carolinensis has become established at the San Diego Zoo. Who knows which of the zoo’s denizens will be the next to adopt an anole?
This video, shot by Johann Prescher, is of an Anolis lineatus from Curaçao, gracefully jumping from one tree to another. Note, however, what it does just as it lands, pulling up its forebody to contact the trunk with all four legs simultaneously, like a flying squirrel. The mechanics of jumping in anoles have been well-studied, but the mechanics of their landing, not so much. Good research project waiting to be done!
A letter in Anole Annals’ inbox. Can anyone help?:
I am a student from xxx High School in New York. As a science research student interested in phylogeny of squamata, I have come across Bayesian Inference quite a lot. I have spent a lot of time researching bayes theorem and how it relates to phylogeny, but have yet to find an article that makes sense to me as a sophomore in High School. Do have an explanation to bayesian inference and how it used in phylogenetic research? Being interested in phylogenetics, I have looked into researching phylogenetic relationships of Pogona based on molecular data. I have yet to find a taxonomic revision of Pogona, the latest one I found only used morphological data, Taxonomy of Pogona (Reptilia: Lacertilia: Agamidae) by Witten in 1994. Do you think this would be a good topic for me? In addition to selecting genera to study, I have had trouble understanding the methodology that goes into phylogenetic studies. For the most part the methodology resembles collecting DNA data through PCR, then bayesian analysis is run using MrBayes. Can you explain to me the process of choosing primers for use in PCR? Can you explain what and how data is inputted into MrBayes? Would you or anyone you may know possibly be interested in assisting me with my research in the phylogeny of squamates?
Like many other biodiversity journals, the contents of the Bulletin of the Museum of Comparative Zoology are available on the Biodiversity Heritage Library. However, the BHL can be somewhat cumbersome to deal with, if not downright counterintuitive. Just today, I downloaded Lazell’s spectacular, classic monograph on the Lesser Antillean anoles, full of detailed descriptions, lovely illustrations (as above) and incisive commentary. Every digital library should have a copy, and so here’s your chance to get one easily, by clicking on this link. But note: the link apparently is only good for 30 days (and someone had to try it twice to get it to work, so be persistent). Also note: it’s a big file, so be patient as it downloads.
Enjoy! And after you look it over, write a nice comment for Skip, AA‘s all-time leading commenter, to read.
George Gorman, guru of all things Anolis, writes in:
49 years before Barack Obama’s historic visit to Cuba , I made a historic visit to Cuba but did not visit the Castro brothers, nor was there a baseball game played in my honor. I did, however catch a lot of Anolis,and send a letter to Science about my trip … which was published.”
A recent paper in Science Advances by Daza et al. reported on 12 amber lizard fossils from Myanmar. First author Juan Daza provided an author’s view of the paper two days ago, but I thought I’d add a little more–mostly some cool visuals and links to reporting in the press–here. Particularly notable were a specimen that appears to be on the evolutionary way to becoming a chameleon and gecko with different toepad structures. You can read nice summaries of the articles in the Christian Science Monitor and the BBC. Anoles even make an appearance in the nifty figure summarizing what we know about fossil amber lizards (more on amber anole fossils).
A common question is whether green anoles (A. carolinensis) and brown anoles (A. sagrei) can interbreed. I am unaware of any hybrids between the two species, and given their long evolutionary separation, it seems unlikely that they could reproduce successfully. Nonetheless, occasional reports of interspecific matings are made, and here’s another.
Mitchell Gazzia posted this photo on his Facebook page, and provided these details:
Took place in late June of 2012 in Melbourne, the Lake Washington area in Brevard County…very close to the intersection of Lake Washington and Turtlemound roads.
Student researcher Maria Jaramillo lands Sigma Xi grant studying green anole lizards
by Carlos Anchondo ’14
Two male green anole lizards meet in the forest. One lizard has infringed on the territory of the other, who now feels threatened. In a bout of competition, the lizards extend their dewlaps, the flaps of skin beneath their lower jaw, and a faceoff ensues.
Observing this aggressive act, neuroscience major Maria Jaramillo ’17 pondered how the dewlap is processed as a stimulus in the lizards’ brains. She then compared this hostile social behavior with a non-social interaction, like a lizard’s observation of a leaf. How does the lizard’s brain handle each interaction? At what point and why is the brain more active?
To answer these questions, Jaramillo applied for and was awarded a $1,000 grant from Sigma Xi, The Scientific Research Society. The grant money will be used to purchase antibodies, used for immunocytochemistry, as well as other supplies like microscope slides. Jaramillo studies in the lab of biology professor Michele Johnson, a researcher of the evolution of lizard behavior, and collaborated with Johnson during the grant proposal.
“I find the brain very interesting because it controls everything that we do,” Jaramillo says. “I love to study lizards because the wild environments they live in provide all kinds of stimuli, and I want to understand how they process it all.”
For the study, Jaramillo recorded a video of a green anole lizard exposing its dewlap and edited the video, scrambling the pixels of the lizard but maintaining the exact same colors and movements. After removing the social context, Jaramillo analyzed a lizard’s reaction to the modified video in comparison to its reaction to the original. She also tested two lizards together and then played the video without the lizards as an additional control. The lizards were placed in arenas, and Jaramillo observed them using GoPro cameras.
Jaramillo was notified in December 2015 that she had received funding and couldn’t believe the news. She excitedly called Johnson to share her elation, as Jaramillo had been turned down for the grant during the previous application cycle.
“This was a super cool process because Dr. Johnson and I literally built this project together,” Jaramillo says. “I did a lot of the decision making and, even though lizards are not what I am going to study for the rest of my life, it has given me a lot of research experience where I have worked directly with a professor.”
Applying twice for the grant meant that Jaramillo and Johnson received feedback from Sigma Xi evaluators following the initial application. Jaramillo says she was not discouraged after being rejected, but eager to learn how best to improve her chances. A peer tutor for Johnson’s biology class, Jaramillo encourages other not to give up and to “just keep trying.”
From Katy, Texas, Jaramillo plans to pursue medical school after Trinity. Her motivation is to help others with their medical needs and keep them in good health. She says that she has always loved science, and views medicine as a rewarding way to put her interests to good use.
“Health is the thing everyone needs to survive,” Jaramillo says. “For someone who wants to go into medicine, understanding how to conduct research like this is critically important. Studying at Trinity has made me sure that I want to attend medical school and become a doctor.”
Carlos Anchondo is a writer and editor for University Marketing and Communications. He is a 2014 Trinity graduate and can be found on Twitter at @cjanchondo or at firstname.lastname@example.org.
The caption says: At first look this image may just look like an Amazon green anole (Anolis punctatus) climbing a tree; but look a little closer… there is a cryptically coloured cricket fooling the predatory eyes of the lizard. Jack Mortimer Photography
Writing on the blog Cultured Vultures, Karl Koweski reports on a community college classroom exercise that involves coloring in anole ecomorphs and Caribbean anoles with different colored crayons. Surprisingly, he’s not thrilled about it.
I’m always amazed by the ability of anoles to survive–even prosper!–with dramatic injuries. How could a lizard get by missing half of a hind leg? How does it capture prey or escape predators? Display credibly? But they do. We’ve reported incidents of three-legged lizards before, and are always looking for more examples.
The photo above is a fine example, reported by Karen Cusick on Daffodil’s Photo Blog. The brown anole also had a mysterious dent on its site. Must have been a traumatic event.
“Can anyone tell me the source of the record of Anolis carolinensis/porcatus on Canouan in the St. Vincent Grenadines?
It is listed as a waif in the Lesser Antilles island list by Henderson & Breuil (pp. 148–159 in Powell & Henderson, 2012. Island lists of West Indian amphibians and reptiles. Florida Mus. Nat Hist. Bull. 51: 85–166).”
From Yesterday’s Jeopardy round. Thanks to Joel McGlothlin for the videography, and Ian McGlothlin for the soundtrack. Note also Alex Trebek’s pronunciation of anole. And further note that Jeopardy has an understandable thing for anoles, having featured another anole question two years ago.
Scott Trageser posted this photo on Herpnation of Anolis leachii eating a gecko in Codrington, Barbuda. Here’s a few more details he sent while travelling in Madagascar: “The story was, I was photographing the gecko for a distribution note and the A. leachii came down and grabbed before I could even pull the shot off! The leachi would stay high in the trees so despite being large, we seldom saw them.”