Author: Jonathan Losos Page 66 of 130

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.

Could a lizard stowaway on a succulent?

We hear a lot about invasive anoles–A. sagrei and others–showing up all over the place: Singapore, Taiwan, you name it. But how do they get there? I was recently reminded of an article by Gad Perry and colleagues in the journal Iguana (now Reptiles and Amphibians: Conservation and Natural History–a quarterly journal available online and worth a look). Perry et al. examined a barge delivering a large number of potted plants to the small island of Guana in the British Virgin Islands. The plants came initially from Florida, but had been sitting in a nursery on a nearby island for at least ten days. What would they contain?

To find out, the investigators laboriously inspected the plants, all 220+ of them, one by one. And sure enough, there were stowaways: six juvenile Puerto Rican crested anoles (A. cristatellus); a dwarf gecko, Sphaerodactylus macrolepis; also, an immature spider, three snails and nests of the red fire ant. In addition, the barge carrying the cargo contained two other lizards, Ameiva exsul.

And remember, this is one just one shipment. Now, in this case, all of the lizards were natives, as were most of the invertebrates. But imagine all of the plants being shipped out from Florida, containing brown anoles, Cuban treefrogs, and who knows what else? My prediction: it’s just a matter of time before brown anoles are everywhere in the urban tropical world.

Evidence From VD That Small Territorial Males May Be Successfully Mating

By Jonathan Losos

On September 2, 2013

In New Research

The parasite in question. Photo from an Anole Annals post by Gerrut Norval.

Recently, Bryan Falk wrote an interesting report on how nematode parasites are passed from one anole to another by sexual contact. He summarized a fascinating paper by Langford et al. in the Journal of Parasitology that convincingly demonstrated this phenomenon. In reading that paper, I found one idea they suggested in the Discussion to be particularly intriguing. I’ll let them describe it:

“Our finding that C. penneri” (the nematode parasite) “is transmitted by copulation has some interesting implications for the host’s reproductive and behavioral biology. Anolis sagrei reproduces in a female-defense polygyny, wherein large males (e.g., SVL = 50 mm) establish and maintain territories containing multiple, relatively small females (Schoener and Schoener, 1980). In Anolis mating systems, young males are generally thought to have little mating success because they are excluded from females by large territorial males (Losos, 2009). In contrast, our parasitological results suggest that small male lizards are copulating with mature females and becoming infected with a sexually transmitted parasite. Thus, our results provide some support for the female mimicry hypothesis (Orrell and Jenssen, 2003) and/or the ‘‘dear enemy’’ phenomenon (Paterson, 2002) in anoles. This insight into A. sagrei reproduction should encourage anologists to reconsider the role of covert and satellite males in anole mating systems where C. penneri infects small male lizards. In conclusion, the major contribution of our study is the establishment of copulation as the route of transmission for C. penneri between lizards and the discovery of both ecological and physiological host specificity in these worms.This study also provides insight into the host’s biology, specifically support for the female mimicry hypothesis in anoles proposed by Orrell and Jenssen (2003).”

I queried Gabriel Langford, “just how small are these infected males?” He responded: “We sampled an evenly distributed group of females and males that ranged from a few days old to large (male SVL 68mm) adults. If memory serves (I’m on my tablet, no data in front of me), at least 35 of the 87 males fell into the range of 34-50 mm. Also, we had several males just above (infected) and below (uninfected) the 34 mm cut-off, which allowed us to be fairly confident about this number in A. sagrei.”

These results suggest that even quite small males may be mating, even though they are far too small to hold a territory. The idea that “sneaker” males may exist in anole populations has been suggested before, but not demonstrated. The occurrence of such matings has all kinds of interesting implications for anole sexual selection and evolution.

Rapid Color Change In Anoles

By Jonathan Losos

On September 1, 2013

In Natural History Observations

Anolis gundlachi. Photo by Alejandro Sanchez.

Anolis gundlachi 10 seconds later. Photo by Alejandro Sanchez.

West Indian photographer and natural historian extraordinaire Father Alejandro Sanchez sent in these photos, commenting “I took these two pics less than 10 seconds apart from each other – the time it took for me to modify the flash’s settings. Yet the lizard noticeably changed color patters in such a short time, surely for being scared by my proximity. Anolis gundlachi is one of my favorites.”

And note those blue eyes!

Anole Sculpture

By Jonathan Losos

On August 31, 2013

In Anole Art, Literature, and Humor

On our recent field trip to Mexico, we were joined by AA contributor Ramon E. Martinez-Grimaldo. Ramon kindly gave me this lovely sculpture of Anolis sagrei. It’s the nicest anole sculpture I’ve ever seen! It’s made of resin and the artist is Luis Ivan Huerta. Check out his website; in the section “dermoplastias,” he put a picture of the anole’s sculpture. Perhaps Luis will see this post and tell us whether it’s possible to order other anole creations!

Anole Eats Morpho Butterfly

By Jonathan Losos

On August 27, 2013

In Natural History Observations

Photo by David Herasimtschuk

David Herasimtschuk took this striking photo along the Rio Carbon near the town of Bribri in Costa Rica. Here’s what happened: “The story of how I photographed this image was very bizarre. I was working my way up a stream with the intent to film poison frogs along the bank, and I saw the blue morpho floating down the stream. It was fluttering and still alive, but was being harassed by a school of very hungry fish. Feeling sorry for the animal and curious to see a blue morpho up close I pulled it out of the water. At that point it wasn’t doing to well, but I felt bad throwing it back in the stream, so I placed it on a branch thinking if it might be able to rest and dry off. I then left to film frogs, and came back about a half an hour later. When I returned the butterfly was gone. Initially I thought it had survived and flew off, but then I saw a bright blue shape in the mouth of stream anole a couple feet from where I had placed it. It was a strange set of events, and it definitely reinforced my belief that when you live in a tropical forest everything wants to eat you.”

Anolis Taylori’s Massive Dewlap

By Jonathan Losos

On August 26, 2013

In Anole Photographs

This photo is a treat from tweet-o-sphere, posted by Miguel Angel Zapata, who did not respond to my request for more information. And that’s really all I’ve got to say. Anolis taylori is a relatively little-known anole from southern Guerrero, Mexico. As far as I’m aware, there’s only been one paper written on this species, by Fitch and Henderson in the Journal of Herpetology in 1976 (and this paper, in turn, has only been cited five times). The species apparently is usually round in boulder piles, on the sides of rocks, as well as on rocks and trees. Does anyone know any more about this species?

Here’s the abstract to that paper, which also concerned Anolis gadovii:

Anolis gadovii and Anolis taylori are medium-large, saxicolous anoles of southern Guerrero, Mexico. The first named species is confined to a small area near Tierra Colorada, about 50 km inland, the second is limited to the immediate Coast Range in the vicinity of Acapulco. For both the habitat is on steep, wooded slopes with piles of large, loose boulders. Compared with other anoles, these are relatively stenothermic and tolerant of high temperatures, with a preferendum between 29 and 30 (at least for A. taylori). The habitat of A. gadovii, especially, is xeric, and during the dry season the anoles tend to stay deep in the rocks where temperature remains low and humidity is high. In both species reproduction is suspended during the drier part of the year and by the beginning of the rainy season in July the population consists essentially of adults. In areas of favorable habitat with high population density of A. taylori many home ranges were found to overlap. Favorite perches and look-outs were used by a succession of individuals with frequent territorial contests. Males of A. gadovii and A. taylori are about the same size, females of A. gadovii are somewhat smaller, and females of A. taylori are markedly smaller. Anolis dunni, a non-saxicolous species living at somewhat higher altitude, is like A. taylori in many of its characters, and is annectent to other montane species.

Coming Soon To A Theater Near You

By Jonathan Losos

On August 24, 2013

In Anole Videos, Education and Anoles

Half Green, Half Brown Anole

By Jonathan Losos

On August 21, 2013

In All Posts

No, it’s not a hybrid, but why do some anoles do this? And how? Read all about it in a recent post on dust tracks on the web.

Photo by Luke Mahler.

I have noticed things like this myself. Some times when you noose a lizard, the scales underneath the noose turn dark. And so species show patterns when they are stressed that they don’t normally flaunt, like the A. garmani below. Anyone have thoughts or similar observations? Or a better photo of the phenomenon in garmani? Some images online suggest that males do this to a lesser extent when being aggressive to other males.

Demeaning Comments From The South

By Jonathan Losos

On August 18, 2013

In All Posts

I was communicating recently with an eminent Gondwanan herpetologist, one who has published far and wide on many issues pertaining to many species. I remarked that it was time that he/she reached the pinnacle and worked on anoles. I received this response:

“To my mind, an anole is a little like a bicycle with training wheels – quite useful for youngsters to practice on and develop their skills. But just a pale shadow of the subtlety and sophistication of real lizards. They just make it too easy to get lots of papers in good journals, and discover neat things. Where’s the challenge?”

Brown Anoles Will Display At Inanimate Objects

By Jonathan Losos

On August 17, 2013

In Natural History Observations

If I were a brown anole, I’d take offense at a flag like this, too!

Pat Shipman from the AA Little Cayman Bureau checks in:

The observation that anoles nod at inanimate objects (or possibly at anoles the observer hasn’t spotted) is not new.

A few days ago, I watched an adult male sagrei repeatedly unfurling his dewlap and displaying… at an orange landscaping flag that marks the location of a large septic pipe underground. What was most interesting is that the flag was fluttering in the breeze and that it was a shade of orange almost exactly the same as the sagrei’s dewlap. Alas, I did not have a camera handy to record this event.

Has anyone else noticed sagreis paying special attention to orange objects?