Annie Proulx's comments on Brokeback Mountain's genesis and the movie. Highly interesting. In fact, I did most of the writing while I was driving. The most difficult scene was the paragraph where, on the mountain, Ennis holds Jack and rocks back and forth, humming, the moment mixed with childhood loss and his refusal to admit he was holding a man.
DNA stuff: scientists poking at the body of the 'iceman' found in the alps, frozen since c. 3300 BC, have picked up on something in his DNA to suggest that he was infertile, and that this might have a link to his death. No progeny, no clan for backup, you're alone out there...earlier studies figured out that he was a local and killed by one of his own tribe.
Another example of an absorbed twin embryo, with picture.