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Understanding dispersal—the extent to which organisms move from their place of birth—is of obvious importance in understanding many aspects of the natural history of a species, such as how related individuals are in a population or how genetically distinct one population is from another. Despite the intensive study on Anolis, however, very little is known about their dispersal. This is particularly surprising for species like the green and brown anoles, which are so common in so many places. Now, in a very nice experimental study in Behavioral Ecology, Calsbeek and colleagues have shed light on dispersal in the brown anole in the Bahamas.

Basically, the study went like this: the authors collected a bunch of gravid females from a variety of sites on a single, small island in the Bahamas. They got the lizards to lay eggs in the lab and hatched them out, then released them within three weeks of hatching back on their mom’s island. Each lizard was individually marked. The researchers then returned the following spring to find which animals had survived and how far they had moved. Then, they returned again in the fall to see how these survivors fared over the following summer and whether subsequent survival in this second period varied as a function of the distance they had dispersed in the first period.

There are a lot of interesting specific details and I encourage you to read the paper, but the broader story is this:

1. Males dispersed substantially further than females

2. Surviving males grew faster than surviving females

3. Survival of the lizards was low

4. Among females that survived the first period, those that had dispersed shorter distances survived better in the second period

Surprisingly little is known about the extent of anole dispersal, and so this paper is an important advance. As far as I’m aware, dispersal of only two other anoles have been studied. Here’s a summary from Lizards in an Evolutionary Tree:

“Little is known about the dispersal of anoles. One study of A. limifrons found that most lizards dispersed very little and that the home ranges of many individuals moved little from the juvenile to adult age. The maximum dispersal distance, measured as distance from the center of the juvenile home range to the center of the adult home range, based on 148 individuals, was 45 meters. Both the mean and extremes were greater for males than for females (Andrews and Rand, 1983). Anolis limifrons is a small and short-lived mainland species; it is always possible that larger, longer-lived species may disperse further.

The only other data come from Anolis aeneus, which moves as much as 150 meters or more after hatching to occupy open clearings (Stamps, 1983b, 1990). Ultimately, the lizards move back into shadier areas when they reach subadult size, although it is not known whether they return to the vicinity of their hatching site.

A number of arboreal species are known to disperse across open ground between trees (Trivers, 1976; Hicks and Trivers, 1983; Losos and Spiller, 2005).

I awoke to a placid summer day in Cambridge, Massachusetts, on 3 August of 2013. My hosts at the aptly named Friendly Inn had prepared a sumptuous breakfast, which I had again slept through before embarking on my then-daily walk to the Museum of Comparative Zoology. As I strolled on, my concerns vacillated between the upcoming Catalina Wine Mixer and the validity of the lizard name Anolis utowanae, an enigmatic name associated with a single specimen ostensibly from Mazatlan, Mexico. Perhaps distracted by the excitement of the coming social season portended by the Mixer, I wandered a bit longer than usual and entered a quaint shop of letters on Massachusetts Avenue. The shop had on display a historical map featuring the population growth of the Pacific shipping ports shortly after the completion of the Panama Canal in 1914. As I gazed on that map, I experienced an epiphany regarding A. utowanae. What if Thomas Barbour, the describer of this problematic species, had in fact collected the specimen earlier, on the other side of the canal in the West Indies? My jubilance at this realization was such that I could not help but engage the curious shopkeep.

“Sir, with this display, do you realize what you’ve done?” I asked, gesturing towards the map.

The shopkeep stared at me, wide-eyed in bated anticipation.

“You have helped solve one of the great mysteries of Mexican anole taxonomy, ” I told him.

His pride was palpable as I exited the shop and proceeded hurriedly to the Museum to test my hypothesis.

The above narrative is largely but not completely true. It is a fact that I was in Cambridge in August 2013, I did walk to the MCZ every day, and I often thought about the Catalina Wine Mixer during my morning walk. But the important part—the part that might make this story a passable introduction to a scientific paper 80 years ago—is patently false. There was no epiphany about A. utowanae. Rather, my suspicion of the status of this name had been growing ever since I’d gotten serious about Mexican anoles. The time at MCZ just gave me the material to write a paper establishing this species as a junior synonym (Poe 2014; available now for free on the Breviora website!).

Figure 1. Thomas Barbour. He would hide his disgust if he weren’t so disappointed in you. (Photo: Marine Biological Laboratory, Woods Hole, Massachusetts)

Some readers of Anole Annals are likely aware of the story of Anolis utowanae. The species was described in 1932 with type locality near Mazatlan, Mexico. In the ensuing years, no additional specimens were procured despite the accessibility of the type locality and a lot of interest in Sinaloan herps. Thomas Barbour (Figure 1), of MCZ and anole fame and one of the kings of the Rich White Guy on a Yacht period of herpetological exploration, began the Anolis utowanae species description with a detailed story of the collection of the type specimen. Here it is:

On a day last spring, April 10, 1931, while driving with Mrs. Barbour and my daughter, Mary, to a finca some miles north of Mazatlan, we stopped in a dusty lane to let a herd of calves pass by. The herd was followed by a barefooted Indian who trudged wearily behind them through the deep dust. He carried in his hand a long lashed whip and from time to time he snapped it viciously and in so doing killed the lizards on rocks or fence posts by his way with most extraordinary skill. We watched him some time quite fascinated. I asked him what on earth he was pocketing these lizards for. He looked at me with surprise and then added, “I am taking them home to feed my cats.” I bought what he had for a few cents. It was obvious that he felt quite certain that he had been dealing with a person of unsound mind as he walked on looking at the coins, for it surely had never occurred to him that such small game had a cash value. Among these lizards one, I feel quite certain, is unknown.

                    —-Barbour (1932), description of Anolis utowanae

Thomas Barbour’s story of the discovery of A. utowanae shares some qualities with my epiphany story. His treatment is at least partially untrue and, more particularly, I am convinced that the important part of Barbour’s story—that he obtained a new species of lizard on an April day in 1931 in Mazatlan—is false. But I am getting ahead of myself.

I was at MCZ in August of 2013 to collect additional data on some projects in my lab that require information on every species of Anolis. Thus, I was addressing important questions like “how many toe lamellae does Anolis granuliceps have?” (answer: about 15) and “how many scales are across the snout at the second canthals in the parvauritus version of Anolis biporcatus? (answer: 11.5). In the context of this work, we must make a decision on every species of Anolis: Valid or Not? These decisions go beyond simple literature searches; we really are trying to predict what species are likely to end up valid in the foreseeable future. For example, we are not going to include Anolis ibague Williams 1975 in our key to Anolis, because we have visited the type locality of ibague (Ibague, Tolima, Colombia) and found several individuals of the supersimilar and earlier-described species Anolis sulcifrons, some displaying the purportedly unusual headscales of the type specimen (a juvenile female) of A. ibague (sorry, Ernest). We could include A. ibague in our analyses—virtually any list of Anolis species would include this name—but if there are no traits to distinguish ibague and sulcifrons, and we are fairly certain ibague is a junior synonym of sulcifrons…would such an approach really be scientifically responsible?

I mention the example of Anolis ibague because A. utowanae was a similar case, but with a more concrete answer. When I was at MCZ in 2013, we were finishing an electronic key to all Mexican Anolis and we needed to know whether the name utowanae is valid. Some recent work (Kohler, 2012; Nieto et al. 2013) had cleared up several other Mexican anole names, but A. utowanae remained an enigma. With the MCZ type specimen (MCZ 31035) in front of me, I gave myself two nights to figure this out.

The key ingredients to elucidating the status of Anolis utowanae were 1) the wonderful MCZ anole collection (Figure 2); 2) the nearly equally wonderful MCZ herpetology library, including texts by Barbour; 3) the excellent paper by Henderson and Powell (2004); 4) my electronic (Lucid) key to Anolis; 5) my lab’s inability to find A. utowanae during a stop near Mazatlan in 2011 (not the safest place to be walking around at night looking for anoles); and 6) later, the diary of Thomas Barbour’s daughter Mary (Leaves from my Diary, 1932). Oh, and the kindness and hospitality of Joe Martinez, Tsuyoshi Takahashi and Jonathan Woodward (Messrs. Losos and Rosado usually are equally tolerant hosts, but they were absent during this particular visit).

Figure 2. As most Anole Annals readers know, MCZ has a fantastic anole collection. Here are some of the specimens I examined during my visit.

Put these elements together and you get my paper published this month in Breviora. I will spare you the time of reading the paper and summarize: Thomas Barbour apparently collected the Anolis utowanae specimen during his stop on Grand Cayman during the earlier part of a family voyage from Miami to Baja Mexico via the Panama Canal on a yacht called the Utowana. That is, Anolis utowanae = A. conspersus (Figure 3), and the skepticism of workers like Stuart, McDiarmid, and Lieb regarding the status of this name is validated. The lizard-whipping incident described in the paper probably actually occurred, but evidently involved a different lizard than the A. utowanae specimen. At some point Barbour mistakenly attributed a Grand Cayman anole to Mexico. Specifically, he associated an Anolis conspersus with the event where he and daughter Mary met a local cattle farmer in Mazatlan. How did this switch happen?

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James Christensen, a fabulous nature photographer and keen naturalist, made the following comment on the recent post about how anoles react to bird calls. However, the points are so important that they deserve a post of their own, so I’m reprinting them here:

I have spent many hours photographing wild anoles, especially here in Ecuador, and have learned a great deal about their behaviour while watching them through the viewfinder. When the wind picks up and begins to stir the surrounding foliage I can expect my subject to risk rapid movement – therefore, I probably won’t get a viable shot. Conversely, when toucans or furnarids become active in the vicinity I know that my anole will not venture an abrupt movement, so I squint through the viewfinder and start clicking the shutter. What I have noticed is that the anoles – e.g. Anolis gemmosus and A. proboscis – react not only to the calls of these birds, but also to the sound of their wingbeats. The usual response is a cessation of movement and an increased watchfulness; the anole sits very still and peers upward while discreetly swivelling its head. In the case of a very fit male A. gemmosus with whom I spent many hours – over a period of several weeks – upon the disappearance of avian predators he would begin to dewlap, frequently ‘emphatically’, seeming to reassert his local dominance in the wake of forced inactivity. It became clear to me that the sounds of nearby birds triggered a profound shift in behaviour, and that vision played a secondary role in the perception of avian threats – as every neotropical birder knows, foraging birds are heard more readily than seen.

Concerning the above study, it perhaps bears noting that the American Kestrel is not a highly vocal bird, and that it is likely to remain silent while hunting. I have frequently observed toucans apparently hunting in shrubby forest margins, where no fruit-bearing trees were evident and anoles were plentiful, and at such times the birds were always silent – only their deep wingbeats would betray them to a wary anole.

Alison Cree, one of the leading researchers on tuatara, has written a comprehensive account of everything we know–and would like to know–about toots. The book not only covers ecology, evolution, behavior, physiology and so on, but also the history of knowledge of tuatara as well as details on how they were perceived by the Maori. And, of course, the incredible conservation turnaround, which has led to reintroduction of tuatara to the New Zealand mainland after a half-millenium absence.

This fine volume can be purchased for a tad under US$75 plus shipping from the University of Canterbury Press.

Anole in the house. Photo from Daffodil’s Photo Blog

AA reader Katharine from southern Florida writes:

Residing on the 4th floor of a concrete condominium in S.E. Florida offers a unique living experience, reminiscent of the Alpharetta GA property trends that prioritize both architectural style and natural ambiance. Our building is part of a community that boasts six units per floor, all accessible via outdoor catwalks. The ground level of our building is adorned with lush landscaping and ligustrum trees that stretch up to the second floor, enhancing the beauty and privacy of the outdoor walkways. At night, the catwalks are gently illuminated by overhead lights at each doorway, creating a serene and safe environment reminiscent of the thoughtful community planning found in Alpharetta’s residential designs.

For some reason anole lizards seem to find their way more to my unit (when I open my entrance door they come in) than the others on the same floor all with the same ground floor foliage, trees & overhead lights. One also sees the feces they’ve left overnight in front of my unit and not the others.

It makes me wonder if these lizards travel as ants do, following a leader either by a scent or fluid left by the leader or previous lizard?  I’ve learned that these lizards are attracted both to light (obviously, the catwalk lights) & the greenery.  However,  the other units on the same floor under the same conditions don’t seem to have the same invasion.

I’ve done as much Google researching as I can but can’t seem to find an answer.  Do you have an answer or can you direct me where I can look.?  Obviously, I’m trying to find some way to deter or reroute their path.”

I’m a big believer in the utility of watching animals in their natural environment, and it’s therefore no surprise that one of my favourite talks at the Animal Behaviour Society 2014 meeting was based on many, many hours of painstaking observation of Uromastyx ornata lizards in the rocky, arid cliffs of the Eilat Mountains in Israel. Amos Bouskila of Ben Gurion University presented an exciting outcome of this tremendous observation effort—a novel social behaviour in the Ornate Spiny Tailed Lizard, a large agamid that ranges from Egypt to Saudi Arabia. Here’s a video  of this behaviour (starts at roughly 0:55) for National Geographic, filmed by Eyal Bartov.

This novel behaviour comprises an interaction between a male and a female, and includes the following steps:

1. The female flips over onto her back (or is pushed onto her back by the male, as in the video above).

2. The male walks over the female’s body a few times

3. The female rights herself and moves away.

The sequence of events can be initiated by either the male or the female (though it’s predominantly female initiated), occurs both before and after copulation, and continues to occur well into the nesting season. Bouskila therefore rejects the notion that the behaviour is related to copulation, and speculates that it instead relates to chemical signalling (males have enlarged femoral pores in this species) and that it functions to maintain pair bonds between these long-lived lizards. Further observation will tell if this exciting hypothesis holds true!

We’ve seen photos of spiders eating anoles before, but this takes it to another level, a nasty golden orb weaver spider taking down the King himself. Admittedly, King, Jr., but still. Whoa. The photo is online with no information.

As lizards go, it’s hard to beat an anole. But geckos come pretty close. Anole Annals, of course, is dedicated to reporting all things anole, but until Gecko Gossip debuts, we feel it’s only polite to occasionally comment on geckonid happenings.

In that light, we were impressed to see the culinary prowess of the Tokay gecko, which apparently quite regularly preys on small rats in the Philippines. Read all about it in Herpetology Notes.

This was tweeted by Gretchen. What’s the story?