Thank you for your complimentary remarks, many folks here think far less of my arguments!
I acknowledge that sex needs certain conditions to be considered desireable or possible, surely, being threatened by a sabre-toothed tiger is not going to have the Viagra effect on a cave man. I base my belief in the high probability of constant casual sexual activity among prehistoric human populations on the fact that most of that portion of humanity has lived within the tropical zones, which had optimum living conditions for humans at the time, in regards to climate, food supply, etc. Populations living at the edges of the ice sheets were indeed less likely to have engaged in casual sex, since the need to hunt and gather consumed major portions of waking time.
I also question the "need" for a male to have had a female's consent to engage in a sex act, it would have been far more important to have either the acquiescence or ignorance of the alpha male of the tribe, unless of course, one was the alpha male.
What do you base your contention that females have natural cycles of "rut" on? There certainly are times in the menstual cycle that are more conducive to approaching a female, but since human beings are not strictly locked into a "heat" or mating season as are non-primate mammals, I'm interested in seeing your evidence that there is a "rut" cycle in our species.