A two-tailed lizard?

 Posted by at 5:22 am on April 29, 2010
Apr 292010
 

During our fieldwork, we recently encountered a male Anolis cristatellus with two tails. This is the result of a peculiarity of lizards’ tail regeneration process. Like many lizards, anoles can lose their tails if they’re grabbed by a predator (or, it turns out, a biologist!). This process is called “caudal autotomy.” As a defensive tactic, it may seem drastic, but if the predator is distracted long enough for the anole to escape, then a tail is a small price to pay for survival. Eventually, anoles that shed their tails can regenerate them, although the replacement will never be quite as nice as the original.

Male Anolis cristatellus with two tails

If an anole’s tail breaks only partially, however, the tail regeneration process may be triggered when there is still a healthy tail attached to the anole’s body. The result? A second tail, sprouting from the site of injury. In this case, the original tail is the one that curves to the right in the photograph, and the secondary tail is the one that sticks awkwardly out to the left.

The National Geographic / National Park Service Biscayne NP BioBlitz activities kick off tonight with the scientists’ dinner, and the BioBlitz will be in full swing Friday and Saturday. I’ll post a full report next week!

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The vagaries of field research

 Posted by at 6:14 pm on April 27, 2010
Apr 272010
 

Research almost never progresses in a straight line, and this is particularly true of field research. When biologists encounter unexpected obstacles, we often have to improvise new data collection methods or modify our experiments to fit the current situation. I’ve already run into some surprises this year, and it’s been a challenge to figure out solutions.

James Liu inspects arena enclosures at Fairchild Tropical Gardens.

Some of the difficulties are logistical. For example, in one of my experiments, Anolis cristatellus and A. sagrei males will compete for territory in large outdoor “arena” enclosures. The arena experiment will help me determine whether one anole species is competitively dominant over the other. Building the arena enclosures took some time, and when we finally finished them, I quickly realized that the cages were overheating because they were getting too much sun. Yesterday we moved the arena cages to Fairchild Tropical Gardens, a local botanical garden, and with luck the thicker canopy cover at the new site will keep the cages cooler.

Other challenges are biological – sometimes the organisms just don’t cooperate! When I did my preliminary fieldwork for this project last July, A. cristatellus (the Puerto Rican crested anole), was abundant throughout the sites I visited. This year, the situation is quite different – the distribution of A. cristatellus seems to be much more patchy. In some areas, I can find cristatellus relatively easily, while in other areas of seemingly ideal habitat (including areas where cristatellus was thriving last summer), I can scarcely find a single individual. Overall, the population density of cristatellus appears to be substantially lower than it was last year.

A dead Green Iguana (Iguana iguana) along Red Road in South Miami

The cause of this apparent decline is not clear, but it might have something to do with the record-setting cold temperatures that Florida experienced earlier this year. For 12 days in early January, temperatures in Miami averaged 52.7 degrees Fahrenheit, with overnight low temperatures dropping to 35 degrees in the city (and as low as 26 degrees in outlying areas of Miami-Dade County!). For Florida’s exotic anole species, adapted to warmer Caribbean climates, these extreme conditions might have been too much to handle. There were news reports of Green Iguanas (Iguana iguana; an exotic species introduced from Central and South America) literally falling out of the trees during the cold snap, and my friends in South Florida told me they were seeing dead anoles as well.

Whatever the causes, the changes that I’ve observed in the abundance of A. cristatellus pose some problems for my research. I had hoped to conduct a “removal” experiment, in which I would select an area with both species (cristatellus and sagrei) present in reasonable numbers, remove all the males of one species, and observe the effects that this removal treatment had on the remaining species. Such an experiment would allow me to determine the extent to which the two species compete for space and food resources. Unfortunately, it’s proving difficult to find sites suitable for conducting the removal experiment. Ultimately, we may have to modify the experimental design so we can take better advantage of the patchy distribution of A. cristatellus in 2010.

Biologist Jason Kolbe positions a camera and fisheye lens to take canopy-cover photographs

Last week we worked with , a postdoctoral researcher from UC Berkeley and Harvard University, to brainstorm about some alternative research plans. Like me, Jason wants to understand the interactions between A. cristatellus and A. sagrei in South Florida, but Jason is focusing on habitat use and “thermal ecology” – in other words, how these cold-blooded animals use different parts of their habitat to maintain an optimal body temperature. We’ve already come up with some promising ideas, and I’ll be sure to keep my blog updated as they develop further.

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Meet the Everglades

 Posted by at 7:46 pm on April 26, 2010
Apr 262010
 

Hi All,
Just got a short one-page article published in IT magazine about the Everglades. If you’re interested, check it out:

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Formentera

 Posted by at 12:10 pm on April 25, 2010
Apr 252010
 

Since April 1st, I have been living on the island of Formentera, the southernmost island of the Pityuses isles (which includes Ibiza, Formentera and about 40 small surrounding islets) in the Mediterranean (and belongs to the Balearic Islands autonomous community, Spain).

This small and irregularly shaped island is only about 84 square km an its longest distance from one side to the other is less than 19 km. From Ibiza’s most southern point, Formentera lies 6 km south.

The only person on this island who owns enough land to build an airport, refuses to do so. As such, the only way onto the island is by boat from Ibiza. The island itself has only about 8,000 legal residents (only about 5000 of which are here year round), but between the months of May and August the island get a lot of tourists (most of whom are vacationing in Ibiza and only visit for the day).

Formentera is known for its many pristine beaches (and for the fact that these beaches are full of nudists). The coastline here is absolutely stunning and is made up of breathtaking beaches, coastal cliffs, and sand dunes.


The interior also merits a visit. The inhabitants of this island have been cultivating its soils for more than five thousand years. Neolithic burial grounds and cave paintings are some of the more popular things to visit. I’ve also spent a descent amount of time biking around Formentera’s dirt roads through zigzags of rock walls, flower covered agricultural fields, and twisted juniper forests. Everything on the island reminds you that you are in the Mediterranean, particularly the smells. Moose, our dog, has started to smell strongly of Pine, Rosemary and salt.

Sara and Moose got here on April 13th. We have been living in a nice house in the Town of Es Pujols, one of the more popular towns (once tourists get here). The beach right off Es Pujols is spectacular and is just a minute walk from our doorstep.

At the end of the month we’ll be moving into a 200 year-old country home in an area called Ca Mari (refer to Map). The house is rustic to say the least, and is powered by solar panels. We have a huge yard, which has been left to grow wild for the past couple of decades, making it a perfect place for me to build some large enclosures, which I’ll use for some of my lizard experiments. It’s also great for our dog. The house is pretty big. It has four bedrooms two bathrooms and one outdoor shower. So, if you havn’t already thought about visiting, know that you’ll have a place to stay with us when you actually come!

Additionally, the Ca Mari house is just a five minute walk from Formentera’s longest beach (Platja des Migjorn). This 7km long beach has some of the coolest bars I’ve ever been to. One of my favorites being Piratabus (until a few years ago, the bar was actually a big broken-down bus on the beach, hence Pirata BUS).

The aptmosphere here is “relaxed.” The island has a long hippy history and a respectable population to match that history. There are “hippy flea markets” every Saturday in the towns of El Pilar and San Francisco.

One of the things that strikes me about the island is its strong sense of identity, despite the millions of tourists that come every year and fuel Formentera’s economy. All the people here know their islands history and, with the exception of the summer season, seem to live a life that is unique and authentic to this particular island. And they are friendly. Locals seem content with the idea of letting us into their community—not something you find in most places of the world. Sara and I have already made a lot of friends, are invited to all the local gatherings and social events, and are starting to get a grip on the transition from Miami.

Moose is in dog heaven.

Formentera is a dog-friendly place and he can go virtually everywhere with use. Last weekend we went to a wine tasting at a fine-dinning restaurant. When we asked the owner if we could bring Moose in with us he said, “as long as he isn’t a problem drinker.”

I bought a car when I first got here. Even though Sara and I take our bikes most places, its nice to be able to lug things around, or travel long distance quickly. And, if any of you visit, you’ll have transportation around the island.

I’ve been busy the last few weeks getting logistics in order, making terrariums for my lizards, catching lizards (and catching their food- which is a lot harder. Formentera has no pet shops so I cant buy crickets for them and I actually have to catch live invertebrates for my lizards to eat. What a pain.).

I’m here to conduct my dissertation research studying color evolution and sexual coevolution in a lizard species that is endemic to this group of islands. The reason I’m here, and not somewhere else studying lizards is because the lizards in this group of islands have a set of characteristics that make them unique for studying the evolutionary processes that I am interested in. Particularly, each island houses a unique subspecies of lizard that has a different color from any of the other islands. With around 42 island of lizards, that’s a lot of color variation (below is a a few pics of representative color morphs from several islands).

Not only does color vary among populations and among the islands, but it also varies dramatically between the sexes. On some islands females resemble males with respect to color (pic 1) and on others the sexes look totally different (pic 2).

All this diversity in the same trait lets me ask a lot of interesting questions about how traits like color coevolve in males and females.

As my research gets off the ground Ill do my best to keep you updated.

More later…

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Being creative

 Posted by at 9:47 am on April 25, 2010
Apr 252010
 

There are a lot of good photographers these days. Photographic technology has advanced rapidly, particularly since the digital revolution. Modern cameras capture images with incredible resolution, color, and dynamic range. Sophisticated autofocus and automatic exposure controls make it possible for beginners to create images that, a few decades ago, would have been once-in-a-lifetime photographs. In the hands of an experienced photographer, modern equipment can produce truly jaw-dropping results.

These advances in photographic technology have arisen alongside rapid developments in communication. No longer do photographers just share images with a few colleagues at their local camera club. Instead, we post images on our websites, e-mail them to friends all over the world, and submit them to online photo communities like Flickr (for any kind of photography) or Naturescapes.net (for nature photography) to get feedback from other photographers. These online communities offer tremendous learning opportunities for photographers at every level of experience, and bit of friendly one-upmanship pushes everyone to create the best images they can.

Verdin (Auriparus flaviceps), Anza-Borrego Desert State Park, California.

I think these online photo communities are good for photography (especially for beginning photographers), but I also think they have a homogenizing influence on the field. People tend to post images that they think will appeal to everyone, rather than images that they’re not so sure about. It often seems like everyone’s trying to produce the same kind of image. Fortunately, there is a community that breaks the mold: .

I discovered Creative Nature Photography a couple of years ago, and I make a point to peruse its image critique gallery now and then for artistic inspiration. Compared to the images at Naturescapes and the other nature forums, the photographs posted at CNP are “outside the box” – sometimes way outside! Some of them are spectacular; others, to be honest, leave me cold – that’s the inherent risk of creating unconventional photographs. But whether an image on CNP reaches me or not, it inevitably leaves me thinking more than just “that’s a pretty picture.”

The community is managed by a group of Indian photographers, including Ganesh Shankar, a photographer whose unique images I had often admired back when I participated actively on NaturePhotographers.net. Ganesh has an uncanny way of using available light to draw a viewer’s attention to a particular aspect of an image – an animal’s eye, or perhaps an interesting shape in the landscape. His website and blog are worth a long visit.

Verdin (Auriparus flaviceps), Anza-Borrego Desert State Park, California

The last time I was in the desert, I tried to capture some creative views of birds that I’d photographed before. It’s tough to break free from the classic front-lit, big-in-the-frame aesthetic that I usually strive for when I’m photographing birds. I’m still a long way from Ganesh and some of the other photographers at CNP. I came away with only one “unconventional” image that I really liked. Compare the shot of the Verdin (Auriparus flaviceps) that I took in the fall of 2008 (above) with the one I took in March 2010 (below). Which one do you like better, and why? I’d love to hear your opinion.

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International League of Conservation Writers

 Posted by at 8:37 pm on April 21, 2010
Apr 212010
 

A couple of weeks ago, I was selected to be an Associate Member of the International League of Conservation Writers (iLCW). When the iLCW’s formation was announced late last year, it sounded like the kind of organization that I’d like to be involved with, so I applied for membership. In this blog, as many of you have noticed, I tend to emphasize the power of visual media to communicate scientific and environmental concepts. But even the best images are impotent without a narrative – the impact of lone images is, at best, ephemeral and diffuse without a compelling story to bind them together. That’s why I’m glad to join the ranks of the iLCW. I’m honored to have a place among such great writers, and I’m eager to learn from them in my ongoing exploration of “science storytelling.” There’s not much on the iLCW website yet, but check out their to read profiles of their Founding Fellows.

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Anoles of Puerto Rico

 Posted by at 7:29 pm on April 16, 2010
Apr 162010
 

Male Anolis gundlachi, El Yunque National Forest, Puerto Rico.

As most of you know, I’m studying anoles — small lizards in the genus Anolis — for my Ph.D. dissertation. I was just in Puerto Rico with my two field assistants to gather some male Anolis cristatellus for behavioral experiments. While there, we observed and captured half a dozen anole species, representing considerable variation in size, shape, and color.

Male Anolis evermanni, El Yunque National Forest, Puerto Rico.

Anoles in the Greater Antilles (Jamaica, Hispaniola, Cuba, and Puerto Rico) can be classified into different groups, called “ecomorphs,” based on their morphology and microhabitat use. The ecomorphs are named for the part of the habitat that they tend to occupy most often (e.g. “grass-bush,” “trunk-crown,” etc.). The two anoles I study, Anolis sagrei (introduced to Florida from Cuba) and A. cristatellus (introduced to Florida from Puerto Rico), are both “trunk-ground” anoles, so they have very similar lifestyles. That’s actually why I chose to study these two species — since they have similar habits, I expect them to compete to a greater extent than many other species. You’ll see plenty more of A. sagrei and A. cristatellus over the next couple of months, but I want to highlight some of the other species we encountered.

Male Anolis stratulus showing orange dewlap, Puerto Rico. Photo used with permission from James Liu; all rights reserved.

Anolis gundlachi is another trunk-ground anole, replacing A. cristatellus at higher elevations in Puerto Rico. I think its blue eyes are pretty cool! A. evermanni and A. stratulus are both trunk-crown anoles, which tend to perch higher and use more peripheral branches than trunk-ground anoles. As a side note, Florida’s only native anole, A. carolinensis, isn’t formally included in the Greater Antillean ecomorph classification scheme, but it is quite similar to trunk-crown anoles in most respects. Finally, we found two “grass-bush” anoles, A. krugi and A. pulchellus. We also missed a few ecomorphs completely, so I have a few good reasons to return to Puerto Rico!

Anolis krugi, El Yunque National Forest, Puerto Rico.

One of the most interesting aspects of the ecomorph story is that the same suite of ecomorphs occur on each of the Greater Antillean islands. Since the species within an ecomorph share many characteristics, you might expect that they are more closely related than species belonging to different ecomorphs. But this is not the case — instead, the ecomorphs have evolved independently on each of the four islands. In other words, on each island, the different ecomorphs all arose from a common ancestor. Jonathan Losos (Harvard University) and colleagues described this pattern in their paper “Contingency and Determinism in Replicated Adaptive Radiations of Island Lizards,” published in the journal Science in 1998.

Male Anolis pulchellus, Fajardo, Puerto Rico.

Special thanks to my friend Yoel Stuart (a Ph.D. student of Jonathan Losos and a fellow anole-ologist) for helping me identify my Puerto Rican anoles!

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For those who missed it: my interview with National Geographic

 Posted by at 8:30 pm on April 15, 2010
Apr 152010
 

Neil Losin in a Costa Rican wetland with a young American Crocodile (Crocodylus acutus). Photo © Nate Dappen.

I posted this link on Facebook last week, but in case you missed it, I was interviewed by National Geographic editor David Braun about my research (which is partly funded by a National Geographic Young Explorers Grant) and my participation in the upcoming Bioblitz in Biscayne National Park. The Bioblitz is a 24-hour biological inventory, co-organized by National Geographic and the National Park Service. It involves scores of biologists like me as well as members of the public, who can join inventory teams led by scientists. Follow the link to read more! Supposedly, the interview went over well at NG and actually made their in-house “intranet” for the day!

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Mission accomplished in Puerto Rico, getting settled in Miami

 Posted by at 4:46 pm on April 14, 2010
Apr 142010
 

Puerto Rican Tody (Todus mexicanus)

Apologies for the protracted silence! I returned to Miami on Sunday from a short trip to Puerto Rico, and I just moved into my “permanent” field home (Nate Dappen‘s house) yesterday. My field assistants and I met our goal of returning to Miami with 48 male crested anoles (Anolis cristatellus), which are now getting used to their new enclosures. Soon I’ll begin an “arena” experiment in which each male will be paired either with another A. cristatellus male or a male A. sagrei in a large screened enclosure, then allowed to compete for territory. I want to know which species is behaviorally dominant in encounters between species. If one species is more likely to “win” such encounters than the other, I’d predict that this dominant species should be aggressive toward the other, subordinate species. The subordinate species, on the other hand, is unlikely to benefit from being aggressive toward the dominant species. The relative dominance of each species, therefore, might influence its territorial behavior toward other species. With luck, my experiments will provide some insight!

Tree snails (Caracolus caracolla)

Puerto Rico was excellent. A. cristatellus was so abundant that we caught all the individuals we needed in just two days. We used one of the non-fieldwork days to explore the beautiful El Yunque National Forest, the only tropical rainforest in the US National Forest system. We saw several of the endemic birds of the island (and the anoles, which I’ll discuss in more detail once I figure out what species they are!). I was especially excited to see my first tody, the endemic Puerto Rican Tody (Todus mexicanus), although the photos I got are mediocre at best. Todies are tiny members of the same order that contains kingfishers and bee-eaters. When I was an undergraduate in Doug Taylor‘s excellent Evolutionary Biology Lab course at the University of Virginia, I constructed a molecular phylogeny (like a “family tree” for species) of the genus Todus using DNA sequences I downloaded from Genbank, an online DNA sequence repository.

Sphingid caterpillar (Pseudosphinx tetrio)

The forest was also full of other interesting organisms, including tree snails (Caracolus caracolla) and some huge, stunning sphinx moth caterpillars (Pseudosphinx tetrio). It was great to see the El Yunque forest, because we found all the anoles we needed for my research along roadsides and in the more contrived “nature” of the University of Puerto Rico Botanical Gardens. I hope I can explore more of the island someday, because it’s quite beautiful.

[I hope the images look ok, since I'm posting this from an un-calibrated monitor!]

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Flowers and lighthouses in Formentera

 Posted by at 7:27 pm on April 5, 2010
Apr 052010
 

I’m finally settled in a small house on the outskirts of Es Pujols, Formentera. Formentera is a small island about 11 miles south of Ibiza. The island is, to say the least spectacular. I’ll post a longer description of the island with some photos and video later this week.

I spent the afternoon out on the Cap de Barbaria, catching lizards and snapping a few pictures. I wanted to share a couple of photos I took this afternoon.

Its spring here, and flowers are in bloom everywhere. Many agricultural areas are blanketed in these yellow flowers, which are alive with pollinators. I got lucky at sunset with some spectacular cloud formations and bright light on the flowers. Check it out:

Earlier in the day, I was at the Cap the Barbaria light house, which gets its name because Africa’s Barbary Coast is just 60 Mile away.

This is one of several unbelievable lighthouses on the island. Ill make sure to send some photos of the others when I post the description of Formentera.

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