| In places without fences, the western fence lizard, Sceloporus occidentalis, lives in trees. It turns out that the five-inch-long lizard also falls out of trees-a lot. A few years ago William Schlesinger, an environmental chemist from Duke University, began studying the circulation of essential nutrients between soil and trees in an oak-studded valley near Carmel, California. He 5 and his two colleagues placed 200 large plastic flowerpots under 40 oak trees to collect falling leaves and twigs. They soon found they were collecting lizards as well. The researchers decided to keep track of the lizard-fall by marking the reptiles and recording their size and sez. In two and a half years, Schlesinger's team recorded 198 fence lizard falls, some of which were the same lizard's second plunge into a pot. Extending their findings to the 10 ground not covered by flowerpots, the researchers estimate that around 5,000 lizard falls take place every year on an acre of Carmel woodland. That's about 10 falls per lizard on average. But some lizards are clumsier than others ; one particularly oafish reptile managed to fall into a flowerpot 5 times in less than a month. " I don't think anyone knew they fell out of trees at anywhere near this number, " says Schlesinger. " It certainly makes the natural history of the 15 species more interesting." |
Anchalee Thongprachan
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