The scientifically un-rigorous interpretation on my part is that women instinctively lie about sex much more than men. This is quite understandable as a woman's survival in the ancestral environment was most often about how effectively she capitalized on her sex appeal. This would involve pretending to be more aroused in situations where she was expected to be aroused (i.e. an alpha male wants her to be aroused) and not showing signs of arousal in situations where she shouldn't (don't let the alpha male see you lusting after a different male).
Now the fact that women responded to a broader range of pictures than men I have no ideas about. Perhaps it is not an adaptation but merely a side effect of women being more empathetic. Do women have more/more highly reactive mirror neurons? Have any studies been done on this?
May I ask why you don't believe the alternative evolutionary explanation? Forced (to some extent) penetration has been with humanity for a long time, and will likely be with humanity for a long time. It was not until relatively recently that it is generally accepted as a bad thing, and even in our "enlightened" age, there is a great deal of misinformation.
Removing the moral implications, rape is really bad PHYSICALLY unless the act is lubricated (the point the article makes). So a woman needs to be PHYSICALLY ready for sex, even if not EMOTIONALLY or MENTALLY willing.
That leads to a decoupling of mental and sexual desire from physical response.
Call me unPC, but that seems to fit the evidence they present!
I can't really think of a specific example but it seems that a whole host of things about humanity would be different if forced sex was the main method of procreation in the ancestral environment.
Now the fact that women responded to a broader range of pictures than men I have no ideas about. Perhaps it is not an adaptation but merely a side effect of women being more empathetic. Do women have more/more highly reactive mirror neurons? Have any studies been done on this?