Is your date going to end well? Body Signals

"Your date's gestures can send you silent signals of desire—or communicate a complete lack of interest. Do you know how to read the message in these moves? "

You know, I really wish I knew where information like this comes from. I think journalists (or in this case phd's) should do a better job of citing things in their articles. While I'm sure there is some published evidence (that is... published in a peer reviewed journal) that these "signs" are what the author suggests they are, I would really like to know whether this is just referring to mice or what.