Rape always involves a sex act because that's part of how we define rape. Forced sex.
On the other hand, rape is just one of various modes of domination. While most domination involves violence, it needn't. It can involve the mere threat of violence or it can be done with nonviolent threats (I'll give you a bad grade; I'll expose your secret; I won't help you if you don't...). We refer to such things as being like a rape or perhaps we even refer to them as rape, but metaphorically.
Primates are big on rape and coercive sex. Evolution has selected for it. It is an effective strategy in passing on the genes of the offender. Among chimps, our closest relatives, the males are wont to separate a female from the troop and act out not the gentlemanly way.
Homosexuality which is strong in nature is strong in humans. Similarly rape is a result of our biological heritage.
But of course the overlay of civilization in general and culture in particular influences the frequency and strategies of rape. Sometimes it is a guy who feels inadequate and is filled with rage who gets drunk and rapes a woman. Sometimes rape is fostered by a culture in which women are merchandise and of less value like an Islamic, Hindu or Christian culture. I would guess that rape is less common in more secular cultures.
War is instructive in terms of the dynamics of rape in which men look down on women. Throughout history rape of women is a spoil of war. And this is ever so true in the 20th century. Then consider the rape of slave women. If you can color your thoughts as a male to conceive of women the way so many christian theologians have for instance it fosters a culture of rape.
Interestingly, from what i know a great deal of rape occurs among people who know each other as opposed to the intruder who busts down the door to assault a single female under cover of darkness. And in a way it seems consistent with evolution that it would be so.
What I don't understand is why dominance and violence would EVER involve the sex act.
I have difficulty understanding how dominance would not get passed on as a genetic trait to future males. Even violence (e.g. male competition for mates) is largely a genetic trait, in some animals. Humans evolved so that intelligence and choice (especially among females) helped mitigate the aggression, but genetically based behaviors can't just disappear overnight (so to speak).
Maybe someday natural selection will start selecting for unaggressive males.
BUT...I can't imagine why.
And maybe the man feels no need or doesn't want to exert power over the woman.
"You know she really wants it....."
That's an attitude I have come across in the past. The idea that all women are whores. I think many guys even hate their mothers.
not my words...
Instead, rape is a crime most often carried out by men who are sexually experienced and connected to the victim in some way. This changing view of rape is no doubt a reflection of better reporting of crime statistics. That in turn is a result of society having begun to take a more expansive view of such criminal acts, which women of earlier generations might not have been willing to report due to fear of social stigmatization. It should not surprise us that acquaintance rapists far outnumber stranger rapists, nor that the modus operandi of sexual assaults differs in the two different contexts. Acquaintance rapists are not necessarily pathological in other social contexts; they rarely resort to the levels of physical force or violence that stranger rapists employ. All this, Thompson argues, should contribute to a view that acquaintance rape accords with evolutionary perspectives about the rationales for male dominance over and control of female sexuality. And as Thompson puts it, even if an evolutionary perspective does not help us understand how to prevent sexually coercive behavior, “it may give us a clearer picture of the enormity of the problem we are dealing with.”
Same reason as why women rape men and men rape men. Sexual frustration, feelings of rejection and/or the urge to dominate someone that is weaker than the said name individual. Majority of the situations tend to relate to somehow the victim and rapist having some type of connection before any incident ever taking place. (Ex. friend, wife/husband, gf/bf etc..)
Is Jessica Knoll the Luckiest Girl Alive?
Any rape account is appalling, but the ones that happen in India seem worse than most.