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.
Anolis sagrei in All-America Park in South Miami. Photo by Janson Jones.
Last month, we had a trio of papers [1,2,3] on the awesome anolifauna of a tiny park in Miami, which currently hosts five anoles, four introduced from Cuba, Hispaniola and Jamaica, and with a fifth, from Puerto Rico, only blocks a way. Now Janson Jones has joined the chorus, adding his observations from a visit in 2011. Check out his fascinating observations on A. sagrei and the gang on dust tracks on the web.
Photo by Karen Cusick.
They say redheads have more fun, but is that true in the brown anole world? We’ve had a lot of discussion of A. sagrei that are overall orangey in color, but less about the coppertop look that seems to pop up in populations far and wide. We certainly see it on some of small Bahamian islands, but not others. The photo above is from Florida, courtesy of Karen Cusick’s Daffodil’s Photo Blog. Who else has seen the redheads, and where? And any idea of their significance?
It’s that time again, time to invite/implore AA readers to contribute posts. All are welcome. Have any interesting questions about anole biology, cool photos? Want to comment on a recent (or not-so-recent) paper of interest? Or tell us about your research plans or results? Anole Annals is a forum for all of these, and anything else anole-related. And now’s a particularly good time, as your trusted correspondent is leaving the country for several weeks. Fear not, there will be reports from the field, but it’s a good time for contributions from any and all! If you’ve never posted before, it’s easy, and instructions can be found here or contact the AA Editorial Offices at anoleannals@gmail.com.
Before. Photo of A. maynardi by Pat Shipman.
After.
Pat Shipman, AA‘s correspondent in the Little Cayman bureau, reports: “We are very familiar with the individuals of A, maynardi that count our house in Little Cayman as their territory. The individual shown here regularly sleeps on our screen porch in the gap at the top of the door. He is shown in May 2011 in the photo on the left. Judging from the landmarks in the photo, his total length was about 23 cm at that time. Early in Dec. 2012, we saw him again and noticed he had lost his tail. By early February–roughly 2 months–he had regenerated about half of his tail (see photo on right). Judging from reported rates of tail regeneration in A. carolinensis, this is rather fast growth. Of course, warm temperatures accelerate growth and the average temperature here year-round is about 85 degrees (Editor’s note: sure, rub it in). We’re trying to get the photos scaled exactly so we can estimate size & growth better, but this seems remarkable.”
I expect that rates of tail regeneration have been reported in anoles, but I don’t know where off-hand. Anybody know of relevant research? Some googling tells us that tail regeneration was a hot topic in the late 60’s and early 70’s and, in fact, there was a paper entitled “Factors influencing rates of tail regeneration in the lizard Anolis carolinensis” by Maderson and Licht (Experientia Volume 24, Issue 10, pp 1083-1086). Am I too lazy to dig out of the internet? Heck no, but apparently it’s not to be found digitally. Sorry! But wait–it is, only you have to look under the journal’s new name, Cellular and Molecular Life Sciences. In any case, here’s the abstract…oops. There is no abstract. But here’s a section from the beginning of the Discussion: “Our results indicate that temperature may influence at least 3 different aspects of the regenerative process…Comparison of results obtained between 21 and 32 °C indicate that the higher temperature accelerates both rates of blastema formation and subsequent regeneration rates. However, the latter process is seen to be considerably more temperature dependent than the former when Q10 values are compared. Finally, temperature influences the final form of the regenerated tail, a smaller proportion being replaced at the lower temperature.”
And, for Pat, here’s the key figure on tail regrowth:
From Maderson and Licht (1968)
Who is this Uwe Bartelt, who has ferreted out such a surprisingly large number of anole postage stamps? Well, you can read all about him. Especially if you read German. And if you do, please give us more details. The photos make clear that he’s got a great setup for anole husbandry, with all kinds of cool anoles. Check it out. And translate it!
Anolis cybotes. Photo by Miguel Landestoy
A while back, we had a post that featured a photo of a male brown anole sticking its leg off the ground and out to the side in an odd manner. Readers speculated that this was to get the body and leg off the hot surface of the ground. AA contributor Miguel Landestoy has sent in a photo of A. cybotes doing more-or-less the same thing, although less awkwardly, and Miguel, too, speculates that this is for thermoregulatory purposes: “the guy may be avoiding the heat on the very reflective surface on the banana/plantain leaf (see that also fingers are also lifted).” This is, of course, reminiscent of the famous dancing behavior of the African lacertid lizard Aporasaura anchietae, which lives in the Kalahari desert and stands on two legs, rhythmically alternating which feet are in contact with the hot sand (check out the remarkable BBC video).
Maybe so, but I’m not convinced. I’ve seen behavior like this many times, and it didn’t necessarily seem to occur in ultra-hot conditions, though maybe I just wasn’t paying enough attention. Thoughts, anyone?
More eye candy for the anole-loving evolutionary biology crowd. This one is a sumptuous photo of A. distichus by inspired photographer and AA contributor Miguel Landestoy, advertising February 2013 Evolution readers to the presence of a paper on dewlap color by Julienne Ng and colleagues, about which we have already reported.
Astute readers will realize that this is the fourth time since mid-2010 that Evolution‘s editors have had the wisdom to put an anole on the cover. Anyone remember seeing a stickleback or cichlid there?
The most recent issue of Herpetological Review (December 2012) includes an article by Ted Townsend, “Proposal to Alter Anole Taxonomy and Ecological Nomenclature.” Townsend does an admirable job of summarizing the issues and, most importantly, includes a shout out to Anole Annals (“an internet forum frequented by anole researchers”). Also notable is the wacky photo that appears to the left of the article (and the left of this text).
On sale at Walgreens
Is this a long-tongued anole or an anole-shaped chameleon? And, regardless, can a lizard subsist on a lint-based diet (which would include, I would presume, table crumbs and dead insects)?
Figure 3 from Helmus and Ives (2012)
For 50 years, scientists have been cataloguing the relationship between area of islands or other patches of habitat and the number of species they contain. In general, the bigger the area, the greater the number of species. In recent years with the rise of interest in incorporating a phylogenetic perspective to all manner of questions, some have wondered how the phylogenetic variety (the degree of relatedness among species) changes with area. In an important new paper, Helmus and Ives take a theoretical perspective to understand what the expectation is for the relationship between phylogenetic diversity and area. Most excitingly, they illustrate their method using data from anoles on Caribbean islands.
Here’s how they describe what they’ve found: “While there was a strong relationship between Anolis species richness and Caribbean island bank area (Fig.3A; Losos 1996, Losos and Schluter 2000), we found no overall relationship between Anolis phylogenetic diversity and island bank area (Fig. 3B) …The greatest variation in phylogenetic diversity was associated with the overall level of in situ speciation … [T]here is a strong PDAR for the seven Caribbean island banks with at least one in situ speciation event (Fig. 4A). The estimated phylogenetic diversity values of these seven banks are dominated by in situ speciation as opposed to among-island allopatric events (Cuba had 2, 47, 49 colonizations, in situ events, species richness, respectively; Hispaniola had 4, 33, 37; Puerto Rico had 3, 11, 14; Jamaica had 1, 5, 6; Guadeloupe had 1, 3, 4; Grenada had 1, 1, 2; and St. Vincent had 1, 1, 2). The strong Anolis SAR causes a strong positive PDAR for these banks because species richness and the number of in situ speciation events positively correlate (Figs. 3A and 4B). If island assemblages were only derived from in situ speciation, then, according to the neutral macroevolutionary model we used, phylogenetic diversity is expected to positively increase, and then plateau with the number of in situ speciation events (Fig. 4C), which is the same relationship we found for the seven island banks (Fig. 4B). On at least the four Greater Antilles islands, island area sets a limit to the number of Anolis species that can arise via in situ speciation (Rabosky and Glor 2010). Thus, when there are no external colonizations that add large amounts of external evolutionary history to island assemblages, positive PDARs are expected.
It is the balance of ancestral colonizations to in situ speciation, therefore, that affects regional phylogenetic diversity. This balance is thought to be determined by a race between colonists, where initial colonist species will diversify if another colonist species does not arrive and establish too soon after the initial colonization event (Gillespie 2004). For Anolis, this balance is related to island area, the timing of island emergence and species diversification, and island isolation (Losos 2009). For example, the largest island bank, Cuba, is the center of Caribbean Anolis diversity and was likely colonized twice, by the ancestor of most Caribbean Anolis, and possibly to all Anolis (Nicholson et al. 2005), and more recently by a colonist species from Hispaniola, whose ancestor was originally Cuban (Mahler et al. 2010). Cuba thus contains a large amount of phylogenetic diversity, not because it has received outside colonists, but because it is large in area and contains old diverse lineages that have arisen via in situ speciation. Small and spatially isolated banks such as those in the lower Lesser Antilles (e.g., Grenada) have had few ancestral colonizations and few in situ speciation events that together result in low phylogenetic diversity. In contrast, species assemblages on small and non-isolated banks (e.g., the Acklins bank of the Bahamas) are completely derived from among-island colonization’s, and thus, have high phylogenetic diversity similar to the Cuban bank (Fig. 3B). Macroevolutionary simulations should thus be extended to include these isolation effects. However, the model and the Anolis data suggest that, in general, PDARs should be flat for oceanic islands whose species assemblages are an outcome of both in situ speciation and multiple colonizations.”
Figure 4 from Helmus and Ives (2012).
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