Sexual intercourse in humans is usually a private matter. However, I suppose it doesn’t hurt to ask a factual question about human sexual intercourse from a purely biological perspective, does it? It may supplement my knowledge about the human reproductive system in action.
When two humans have coitus on the matrimonial bed in order to procreate, what is the movement of the pelvic thrust? And how does the movement of the pelvic thrust relate to the angle of the penis at erection and the angle of the vagina of the woman’s body? If the mating of gorillas means pushing down toward the mate, then the sexual intercourse of humans can be inferred as pushing downward, perpendicular to the woman’s body. However, I find a paradox, because the woman’s vaginal opening is facing in the caudal direction, not anteriorly. Perhaps, the movements during sexual intercourse is not anteriorly-posteriorly, but really, a superior-inferior motion? But if the penile penetration occurs in the superior-inferior direction, then wouldn’t that require the erect penis to be 180 degrees (or slightly less) away from the flaccid state? I am aware that an erect penis has varying degrees, but I believe the erect penis points directly in the superior direction (or 180 degrees from the flaccid state) in order to fertilize the female and also lock the man in an intimate missionary sex position, the position most conducive to conception.
Am I right? Since human sexual intercourse is usually a private matter performed in homes and not shown in health classes that discuss sex education, I am not sure what it looks like. :dubious: But thanks to my knowledge of anatomy and physiology, I may be able to use accurate medical/anatomical terms to describe the motions of sex, even if my description is inaccurate.
You must have both internet and real life filters that remove all depictions of sex from your world. Googling “redtube” results in many, many results from the pornographic site redtube. Like most branded websites, you stick a .com on the end of the website brand name and will get there. You don’t have to use redtube, but the world is full of depictions of actual sexual intercourse. There are many educational displays available for your benefit.
Someone posted in this thread, linking to a Youtube video of a MRI scan of sex. Then, that post got deleted. Well, at least I saw the video and confirmed my conjecture.
Heh, it’s funny how this is the stuff that people are trying to hide or keep private. It really isn’t so bad. The MRI scan may have been allowed on Youtube, because it is considered less pornographic or erotic. It must be really hard to get those mirror neurons firing in the brain when looking at black-and-white images of coitus.
Researchers conducted a full-motion MRI with a pair of copulating partners at some point, for science of course. Should be all you need. If you can’t find it, I expect someone can Google it for you.
There’s a considerable amount of flexibility in the human body. If you are copulating face-to-face, then usually the woman’s pelvis is tilted up a bit, so that her vagina can be approached from below (towards her feet) and above (towards her belly), and the man’s lower back is arched a bit, so that his motion is mostly up (towards her head) and a little bit down (towards her back), and the flexibility of the various parts does the rest. You might also bear in mind that intercourse does not usually involve just one fairly rigid position and a lot of precision reciprocating motion. Usually the couple squirm around, shift position, move arms and legs and torso, roll this way and that, bend and arch and so forth. It’s not just a question of arranging the bodies in some static arrangement and then pistoning away, it’s more a continuous semi-fluid whole-body kind of interaction, albeit one centered on the coupling genitalia.
Dr. Pek Van Andel, who won an Ig Nobel Prize for making the first MRI images of a couple’s sex organs while those organs were in use, also made a video of the phenomenon. Here, more or less, is the world premiere. https://www.youtube.com/watch?v=OVAdCKaU3vY
Huh. It seems that it’s not just the pelvic area that is moving and thrusting, but it’s the whole body that is moving forward, so that the penis can thrust into the vagina.
I once heard a news report on TV that sex can give a good exercise. In my mind, I thought sex was a static process, and well, I couldn’t really imagine how that was connected to exercise at all. I merely thought that the penis would become erect, enter the vagina, ejaculate, and exit out, because I learned about erection and ejaculation from health class. No movement. Time passed, and the observations of apes in nature made me realize that perhaps, there was motion, and the motion was pelvic thrusting.
I’ve read that some people favor “deep penetration”. Does that mean that the penis would go further inward until it touches or goes past the cervix? If it goes past the cervix, then does that aid conception, since the glans of the penis would be in the uterus and thus closer to the ovum? I remember the time when I was a college freshman, and some of my classmates were talking about whether a woman could feel a penis in the vagina and the length of the penis. One woman reported that she couldn’t feel the penis so deep inside her. In that case, deep penetration might only bring pleasure to the male while having coitus.
Also, some reports say that women want to “feel like a woman in the bedroom”, or men want to “feel like a man in the bedroom”. I presume they mean sex, as the bedroom is usually the metonym for sex. However, I think the phrase has more to do with gender than sex. Perhaps, it really refers to BDSM that some people employ, where the woman takes on the submissive role, and the man takes on the dominant role?
When Gregor Mendel studied genetics, did he engage in sexual intercourse with women, wait 9 months, and have babies? Of course not. He used pea plants. Pea plants grow faster, and a controlled experiment is easier. Also, it’s more ethical to work with pea plants.