Why This Scientist Keeps Receiving Packages of Serial Killers’ Hair

Those fortunate enough to have a head of hair generally leave 50 to 100 strands behind on any given day. Those hairs are hardy, capable of withstanding years or even centuries of rain, heat and wind.
The trouble for detectives, or anyone else seeking to figure out whom a strand of hair belonged to, is that unless it contains a root, which only a tiny percentage do, it’s about as helpful as a nearby rock.