Image Gallery: Remarkable Bionic Animals

Tortoise on Wheels

Gamera, an African spur-thighed tortoise, had his leg amputated after a life-threatening burn. A swiveling wheel epoxied to his shell keeps the 23 pound (10.4 kg) animals moving about.

Mr. Stubbs' Prosthetic Tail

An alligator stuck with the ungainly name "Mister Stubbs" may need a new moniker now that his stump of a tail has been fitted with a lifelike prosthetic. The alligator, which lost his tail as a youth after a run-in with another gator, was brought to the Phoenix Herpetological Society in 2005 after he and 31 other alligators were discovered by police as part of an illegal shipment of exotic animals. Though there were a few stumbling blocks in the development of the tail — an early version took on water and sank, taking the reptile down with it — researchers are now encouraged that Mister Stubbs seems to be adapting to the new 3-foot-long (1 meter) rubber tail.