Researchers for the U.S. military are studying salamanders and other animals to discover how they can regrow lost body parts.

This combo of photos shows a dead fire salamander from below (L) and up (R) with two heads on display at the Central Magazine of the Scientific Collections (ZNS) of Halle University in Halle, Germany, on February 22, 2013. (Photo credit: JAN WOITAS/AFP/Ge