Not sure if this has been discussed here or not...Animal Planet's documentary about an expedition to Bhutan to uncover "once and for all, yada, yada...", BUT it did include some interesting science by one member, a French geneticist who specialized in sampling environmental DNA. She sampled snow inside of footprints and pulled water from streams to see if any unknown DNA was present. I think this originally aired back in May of this year.  I have been searching around but can't find any document