One of the parts of this study involved quizzing men and women on their likelihood of accepting sex from a stranger using pictures of either an attractive or an unattractive person of the opposite sex to see if that affected the subject's likelihood of accepting the proposition, and found:
For the proposition by the attractive person, women were at 4.09 [out of 7] to 4.16 for men — just about a tie.
Which seems to suggest that, in this particular domain—sex with an attractive partner—men and women are equally desirous. It's the perceived danger (and lower sexual prowess) that the female subjects imagine come with the average proposer that makes them less likely to accept the offer than men.
This seems inconsistent with the notion that women are innately less desirous of sex than men; rather that they have more to lose from a casual encounter (as has been said) so are more guarded when accepting such a proposition.
There was a historical shift in beliefs.
I find this very odd. How could a major cultural lineage be wrong about something so much a part of ordinary experience?
When I say wrong, I don't necessarily mean that we're right, or the ancients were right, though there's a lot of evidence that the Victorians were wrong.
My favorite theory is that people's amount of desire for sex varies sufficiently that there's enough noise to make it easy to see patterns that aren't there. I leave the possibility open that there was a change (possibly dietary) which affected libido levels differently between men and women.
People are sufficiently punitive about sex that there's going to be lies and misdirection to support the current theory about how people are supposed to be.