Scientists have revived tiny animals called nematodes from a slumber that lasted 46,000 years, reports a new study.

The microscopic animals were successfully woken from a state of suspended animation after researchers found them in the permafrost, or frozen soil, that flanks Siberia's northern Kolyma River. A radiocarbon analysis revealed that they hail from a prehistoric era when Neanderthals and dire wolves still roamed the world, and that they belong to a functionally extinct species called Panagrolaimus kolymaensis that was previously unknown to science.