Genetic genealogy -- DNA testing done for the purpose of learning about one's roots -- has been around for about a decade, but a recent development suggests that we've reached the pioneering sweet spot.
One key contributor to a good immune system is good genes. Lately, researchers have been asking, Where did these "good genes" come from? The answer: sex with Neanderthals.
For a long time, the Tocharian civilization was lost from sight as wars and the shifting sands of the Taklamakan desert destroyed them and most of their artifacts. But they left behind items that are hard to ignore.