New Delhi, June 26 -- A piece of 99 million-year-old amber has revealed a shocking sight. It's a fly with a zombie fungus growing from its head. Another fossil in the same amber shows a young ant infected by a similar fungus. The ant and the fly were then trapped in sticky tree sap that became amber.

These are among the oldest known examples of fungi controlling insects, killing them in the process. Chinese researchers studies the fossils by using microscopes and 3D scans.

Lead author Yuhui Zhuang from Yunnan University said such rare finds help in understanding ancient relationships between fungi and insects.

"Overall, these two fossils are very rare, at least among the tens of thousands of amber specimens we've seen, and only a few h...