Higham, an assistant professor in the Department of Biological Sciences at Clemson University, and co-author Anthony Russell studied the moving tail phenomenon on four leopard geckos.
They first anesthetized the reptiles in order to implant electrodes on various parts of the geckos' bodies. Once recovered, the geckos had their tails lightly pinched by the scientists, causing each lizard to release its tail through a series of muscle contractions.
"These muscular contractions cause the vertebra to break in half, and the tail falls off," Higham explained.
He and Russell next placed the tails in a filming arena. Using a high-speed video camera, they determined each tail continued to wriggle, as well as to lunge by pushing with its tip. The tails could flip up to 1.2 inches in height by themselves. The complex movements lasted for up to 30 minutes.
The findings are published in the latest Royal Society Biology Letters.
Previously it was thought the phantom tail movements relied on sensory feedback from the environment. Higham and his colleagues could find no evidence for that.