iPhone Herpetology: Winter AnolesPosted: January 6, 2012
The SICB 2012 meeting in Charleston, South Carolina has been an eye opener, for sure, in many ways. First, the breadth of talks is staggering, ranging from biomechanics to comparative genomics. Second, many anole biologists have attended and it is exciting to mingle and share ideas with people who work on the same organism.
Finally, during a brief excursion outside yesterday, I opened my eyes to find quite a few anoles basking. This was surprising because it was following two days where the daytime temperatures were in the 30s and overnight dipped into the 20s. Freezing! Nonetheless, our favorite green guys were taking advantage of the comparatively warmer 50 degrees and sunny day to do some basking.
Actually, seeing the anoles outside was not completely surprising. Anolis carolinensis occurs at higher latitudes than any other Anolis species (out of ~380 overall), and have conserved the non-hibernating tendencies of their tropical progenitors. For green anoles, the northern range limit is at about the 35th parallel in eastern Tennessee, where it snows and freezes often, and here in South Carolina the winters can be cold as well (as the last few days have demonstrated to us conference-goers). Sandy Echternacht at the University of Tennessee (who helped guide me in my collecting activities in that state) has made a career out out of studying the thermal ecology of these lizards, and has demonstrated that on a wintry yet sunny day an anole can clamber out of its hiding place and bask on a rock to achieve the same body temperature it would if it was summertime (obviously the time it takes to attain thermal optimum – the temperature at which the lizard is most comfortable – takes much longer).
In the spring and summer, basking anoles attain a bright green color, sometimes with striking shoulder patterns of blue. All the anoles I observed yesterday were brown and olive-green in color, indicative of torpor. Since the temperatures have been so cold the past week, these anoles have had a rough time getting out of bed.
- Actual Anoles at SICB 2012 (anoleannals.org)