Studying sand skinks in the scrublands

Sometimes the Zoo’s research does not take place at the Zoo. As part of our collaborative research on the biophysics of locomotion on sand, with Dr. Dan Goldman’s lab in Physics at Georgia Tech, we decided to look into an oddball little creature that appears somewhat like a snake, but still has limbs you’d expect on a lizard. The catch is, the limbs are really tiny, so we weren’t sure if, or how, they functioned.

The animal is the Florida sand skink (Plestiodon reynoldsi) and they live only in the uplifted sand ridge habitat in central Florida. Because of rampant development in Florida, they have lost much of their habitat and so are protected in Florida. Because of their protected status, the Florida Wildlife Commission would not allow us to collect any animals and bring them to Atlanta for studies. If we can’t take the animal into the lab, then we have to take the lab to the animal! A couple of weeks ago, a group of my Georgia Tech research undergraduates, a physics doctoral student, the Zoo’s Lead Keeper of Herpetology Trent Niesen and I loaded up thousands of dollars of high-speed camera equipment and drove to the truly amazing Archbold Biological Station near Sebring, Florida. We set up our equipment in one of their outreach classrooms, and proceeded to brutalize ourselves in the midday heat of the Florida scrub habitat. These lizards are only a couple of inches long, and they spend 99 percent of their time buried in the sand in thick scrub forests. Talk about finding a needle in a haystack! Yowza, these little guys are not easy to find. But, two of my students proudly found a couple.

Perfect—then we put tiny little bits of harmless infrared-reflective tape on their backs and tails and took ultra-high-speed videos and infrared motion recordings. After a handful of trials in our indoors “sandbox” had being filmed, we were to release them as the State of Florida requested. I can’t divulge all the juicy details of our preliminary data at this time, but I can tell you that these things do not move like other burying skinks we’ve studied (e.g., sandfish, Scincus scincus), nor do they move like sand-swimming snakes (e.g., shovel-nosed snakes, Chionactis occiptalis) that we have studied in the lab at Georgia Tech. And, they do, in fact, use those tiny, tiny little legs. Well, they use the hind legs, anyway, as they move across the surface of the soil; we are not yet sure what they do with them under the sand. The even tinier front legs are moving, but we can’t be sure if they are actually helping with locomotion. Needless to say, we are fascinated, and we will be working with the little animals for the foreseeable future. Next trip, we’ll bring down even more expensive hi-tech gadgets. I sure wish these little guys were easier to find!
Joe Mendelson, PhD
Director of Research