Mummies found buried in boats in a China desert have unexpected origins

This week, DNA analysis reveals both the origins of mummies buried in boats in a China desert and the last stand of woolly mammoths in the Arctic, astronomers detect a possible extragalactic exoplanet, an endangered lemur has human-like rhythm, and more.

Extracting ancient DNA is much harder than sending off a swab, but it has uncovered some startling revelations: Scientists learned in 2010 that humans and Neanderthals had babies together, leaving traces in our genes. And DNA from a tiny finger bone found in a Siberian cave revealed a mysterious early human population with whom Homo sapiens also interbred.