A two-headed salamander tadpole has been discovered at a university in Israel, with scientists baffled as to why the creature has mutated.

The tadpole was found in the Community Ecology Lab of the University of Haifa.

Experts have suggested several causes for the mutation, including pollution of water sources, the effect of a dwindling population, or radiation changes.

Researchers at the lab said they have observed an increased incidence of deformity, especially among the limbs of salamanders. However, they said in the past two-headed creatures were far more rare.

The Salamander of Israel is an endangered species because of disturbances to its habitat. The soil and water have been polluted, while much of its natural habitat has been destroyed.