St. Francis and the Lizards

We have now lived in our "new" house nearly three years. The yard came with a small statue of St. Francis. Though we are not Christians, I love the idea of a saint who loved animals watching over the critters who come to visit. From our first days here, there has been one or another Spiny Desert lizard that likes to perch on Francis' head. Here are some of my favorites.

Cedric, a fairly large desert spiny, was the first lizard I named. This is his typical perch--on the side, facing west, his tail relaxed and extending down Francis' cowl. Late in that first summer, I found poor Cedric's body lying on the back porch, his beautiful belly colors still glistening. I have no idea what the cause of death might have been.

Cedric was followed by his girlfriend, unnamed. She was somewhat smaller than Cedric and preferred to sit more securely on the top of the head.

A considerably smaller lizard, whom I named Cedric Jr., appeared the following year:

The lizards have come and gone, but never has warm weather passed without at least one "regular" making him- or herself comfortable on the saint's accommodating head.

This year, I've had a special lizard, a very large female I named Heloise. When I first saw her in this pose, I burst out laughing. 

A few days after I took the photo, I noticed that Heloise had lost her tail. That did not stop her from her favorite activity, however, and finally I discovered why St. Francis' head is so popular. In addition to his function as a sunbathing perch, it turns out he is a hunting blind!

With her tail beginning to grow back, Heloise was in her usual spot the other day. I was puzzled, though, because it was cloudy, not suitable for basking. I was just about to change positions so I could get a shot of her tail stub when she very suddenly leaped off St. Francis' head and literally dived into the lantana bush to the west. I saw her wrestling with a large insect, but couldn't tell what sort it was, or if she managed to eat it. Nevertheless, I feel confident that tailless Heloise will continue to thrive in my Francis-blessed back yard.

Tale of a Lost Tail

The Desert Spiny lizard (Sceloporus magister), is among the most prominent creatures greeting visitors at Tohono Chul Park in the warm weather. Big, bold and beautiful, with striking colors and eye-catching behavior (these lizards, especially the males, frequently do pushups to advertise their fitness and attract mates), spinies say "Sonoran Desert" as surely as does the saguaro.  

Like other members of the Iguanid family (and other lizards, including geckos), a desert spiny can lose its tail to a predator in a process called autotomy, in which the tail breaks along a fracture plane between two vertebrae. Studies have shown that the lizard is handicapped for some time afterward while it grows a new tail, but it is obviously much better off  than if it had been eaten by the predator!

The tail that regrows is not the same as the original, however. Instead of new vertebrae for support, the regrown tail is composed of cartilage, with long muscles running its length (rather than shorter sets of muscles, as in the original tail). Studies have shown that the new tail does regrow nerves, though it is not known how they compare with the originals.

Above is a photo of a beautiful male spiny I saw at Tohono Chul Park this week, who had fairly recently lost his tail. The photo below more clearly shows the cartilagenous new growth. For a photo of an intact male and the female he has just mated with, see the bonus question in my recent nature quiz.