this post was submitted on 14 Sep 2025
56 points (93.8% liked)

No Stupid Questions

43727 readers
1006 users here now

No such thing. Ask away!

!nostupidquestions is a community dedicated to being helpful and answering each others' questions on various topics.

The rules for posting and commenting, besides the rules defined here for lemmy.world, are as follows:

Rules (interactive)


Rule 1- All posts must be legitimate questions. All post titles must include a question.

All posts must be legitimate questions, and all post titles must include a question. Questions that are joke or trolling questions, memes, song lyrics as title, etc. are not allowed here. See Rule 6 for all exceptions.



Rule 2- Your question subject cannot be illegal or NSFW material.

Your question subject cannot be illegal or NSFW material. You will be warned first, banned second.



Rule 3- Do not seek mental, medical and professional help here.

Do not seek mental, medical and professional help here. Breaking this rule will not get you or your post removed, but it will put you at risk, and possibly in danger.



Rule 4- No self promotion or upvote-farming of any kind.

That's it.



Rule 5- No baiting or sealioning or promoting an agenda.

Questions which, instead of being of an innocuous nature, are specifically intended (based on reports and in the opinion of our crack moderation team) to bait users into ideological wars on charged political topics will be removed and the authors warned - or banned - depending on severity.



Rule 6- Regarding META posts and joke questions.

Provided it is about the community itself, you may post non-question posts using the [META] tag on your post title.

On fridays, you are allowed to post meme and troll questions, on the condition that it's in text format only, and conforms with our other rules. These posts MUST include the [NSQ Friday] tag in their title.

If you post a serious question on friday and are looking only for legitimate answers, then please include the [Serious] tag on your post. Irrelevant replies will then be removed by moderators.



Rule 7- You can't intentionally annoy, mock, or harass other members.

If you intentionally annoy, mock, harass, or discriminate against any individual member, you will be removed.

Likewise, if you are a member, sympathiser or a resemblant of a movement that is known to largely hate, mock, discriminate against, and/or want to take lives of a group of people, and you were provably vocal about your hate, then you will be banned on sight.



Rule 8- All comments should try to stay relevant to their parent content.



Rule 9- Reposts from other platforms are not allowed.

Let everyone have their own content.



Rule 10- Majority of bots aren't allowed to participate here. This includes using AI responses and summaries.



Credits

Our breathtaking icon was bestowed upon us by @Cevilia!

The greatest banner of all time: by @TheOneWithTheHair!

founded 2 years ago
MODERATORS
 

There is the issue of an orgasm before penetration, but barring that, does the length of intercourse have any bearing on reproduction?

you are viewing a single comment's thread
view the rest of the comments
[–] exasperation@lemmy.dbzer0.com 3 points 2 weeks ago

The authors modeled a 3d penis and vagina and showed that the penis is able to scoop out paste from the vagina. They then interpret it as that it's "possible" for the penis to have evolved the way it has to scoop out rivals' semen.

The obvious counter to the claim is that anything can be used as a shitty scooping spoon if you try hard enough.

The starting point is the focus on ways in which human sexual behavior is different from those of our closest living relatives, other primates and apes, and how the observed sexual behavior of those other species correspond with physical characteristics in their genitals.

I found this paper to be pretty interesting, and it has a decent summary of why the semen pumping theory sticks around despite some pretty significant issues. It proposes its own theory for the glans penis, but the discussion of the history of the displacement theory is good background on its own.

Basically, species with low sperm competition (where each female tends to mate with only one male) have smaller testes and smaller sperm midpieces (the motor unit that actually drives movement), and species with high promiscuity and high sperm competition, like chimpanzees, tend to have larger testes and larger sperm midpieces. And on these metrics, humans sit towards the less promiscuous side of the spectrum.

So any theory of intense sperm competition is pretty inconsistent with other observed characteristics of human genitals and sperm.

But there also aren't good alternative theories for human penis shape, when comparing all the primates that do or don't have similar features.