Oh the simple joys of reading the comments over at CR. Found a link to this delightful story in the NYT.
Anti Love Drug May Be Ticket To Bliss
"...This hormonal hypothesis, which is by no means proven fact, would help explain a couple of differences between humans and less monogamous mammals: females' desire to have sex even when they are not fertile, and males' erotic fascination with breasts. More frequent sex and more attention to breasts, Dr. Young said, could help build long-term bonds through a "cocktail of ancient neuropeptides," like the oxytocin released during foreplay or orgasm."
http://www.nytimes.com/2009/01/13/scien ... .html?_r=2