IBS Update: Sub-Fossil Anoles on Anguilla

Hello once again from the IBS in Miami. As I mentioned in my last post, anole presentations are a little thin on the ground here (though not around the conference centre where, with the help from some locals, we saw sagrei, carolinensis, equestris and distichus today).

I did have the opportunity yesterday to check out the the second of two anole presentations here – a new look at the sub-fossil lizard communities, with a focus on a question familiar to many readers of this blog: What’s the deal with A. pogus on Anguilla?

Has A. pogus ever been on Anguilla? Nope.

The study is being led by Melissa Kemp, from Liz Hadly’s lab at Stanford. Melissa has re-analyzed lizard dentaries from excavations on Anguilla that featured heavily in an anole character displacement versus taxon cycle debate in the early 90s.

By analyzing the size distribution of anole dentaries dating back 10,000 years on Anguilla, Melissa argues that not only is there a lack of evidence for a taxon-cycle involving A. pogus, but that there’s no evidence that A. pogus has occurred (in meaningful numbers) on the island at all! To further test this, Melissa has sequenced a portion of cytochrome b for five specimens thus far, all of which have turned out to be A. gingivinus, with more sequences coming down the pipeline.

Anoles aren’t the only lizards Melissa has uncovered – with Thecadactylus, Ameiva and Leiocephalus all present. Anoles have dominated the fauna in all but the earliest (and sparsely sampled) time slice and Leiocephalus was historically present (but probably not abundant) but disappeared several thousand of years ago and has not reappeared in the sub-fossil record since.

This was my first exposure to sub-fossil analysis of lizard communities and I was definitely impressed. I don’t have a sense of how much similar work there is in the literature (but I’m sure readers of the blog can educate me), but there seems substantial scope to collaborate with zoo-archaeologists to get more specimens and data on past trait variation and anole assemblage composition.

About Adam Algar

Associate Professor at the University of Nottingham (UK). My research focuses on niche limits and dynamics across scales, from individual organisms to the globe. Mostly lizards.

2 thoughts on “IBS Update: Sub-Fossil Anoles on Anguilla

  1. Thanks for the report Adam. Very cool stuff. I haven’t heard of too much sub-fossil work in anoles but others would know better. Did Melissa have any figures showing how A. gingivinus dentary size (as a proxy for body size) has changed through time?

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