Evolution and Penis Size

[Jm123]

How does anything you've said make my point "invalid"? Yes, some genes are only expressed under certain circumstances or environmental influences, fine. But that doesn't alter the fact that an individual's DNA can't change over the course of a lifetime, which was my central point. The genes you were born with are the genes you'll pass on to any offspring you have, and that's that.

Also I'm pretty sure the recapitulation idea has been discarded for a long time now.

As I said I was attempting to educate. However, I can see you wish to argue, so be it. However, please reread your original post and subsequent post, and avoid the shifting argument. Look you are interchanging DNA and genes in a way that is utterly nonsensical. DNA and genes are not the same thing. That would be like saying a pile of metal is a Corvette. I have no doubt that you are intelligent, and educated. However, I am unaware of when you went through, biology, genetics, embryology, cellular biology, microbiology, evolutionary analysis, or any of the other biology curriculum that covers this topic. Things have changed, and they will continue to change at a very rapid pace.


What I say has no bearing on the fact that what you said is invalid, it is invalid. You said genetic code does not get adjusted, that is invalid. You said genetic code does not change, that is invalid. You said the genes you pass on to your kids are the genes you are born with, that is invalid.

There is no evolution without genes/DNA changing, and those changes have to occur in an individuals lifetime. If there is no evolution, we are all the same. A person does not evolve, but a person's genes/DNA will change. Here is a link to wiki that explains mutations Mutation - Wikipedia, the free encyclopedia

The recapitulation theory is not considered accurate. However Ontogeny recapitulates phylogeny is a term still frequently used, to mean that as we develop we go through stages that look like our ancestors.

[Ivor]

OK, sorry, that last post was a bit out of order. This is clearly your field, not mine. But I was mainly rebutting DrJay's claim, which was that an individual's brain can send out signals that change his DNA in some specific way, which is surely incorrect, right? If it was true, a short guy could become tall - or at least, produce tall children - just by wishing really, really hard that he was tall. It sounds Lamarckian, basically.

I think the exchange that just happened was a bit like a guy saying "the earth is flat", then me saying "no, it's round", and then you saying "no, actually it's an oblate spheroid". Fine, so the earth isn't exactly spherical, but it's more or less spherical, and certainly much closer to being spherical than it is to being flat.

[Jm123]

OK, sorry, that last post was a bit out of order. This is clearly your field, not field. But I was mainly rebutting DrJay's claim, which was that an individual's brain can send out signals that change his DNA in some specific way, which is surely incorrect, right? If it was true, a short guy could become tall - or at least, produce tall children - just by wishing really, really hard that he was tall. It sounds Lamarckian, basically.

I think the exchange that just happened was a bit like a guy saying "the earth is flat", then me saying "no, it's round", and then you saying "no, actually it's an oblate spheroid". Fine, so the earth isn't exactly spherical, but it's more or less spherical, and certainly much closer to being spherical than it is to being flat.

It's all cool. Yes I would agree Drjay's claim was stretching reality. Stressors can change the expression of phenotype/proteins i.e. DNA transcription/translation; I am unaware of any non-abnormal process that affects DNA replication e.g. mutations, cancer, and other undesirable events. In addition (to add to your point), I am also unaware of any research that shows a beneficial application to humans concerning the above mentioned epigenetic exploits. I believe it will eventually come, but right now it is more science fiction than fact.

Lastly, yes that was about the gist of our discourse. However, I would like to point to something in your example. Our improved understanding of the earth's shape is a major factor in our development of the space program. Specifically, everyone launches their rockets as close to the geographical equator as plausible to take advantage of the earth's shape, and rotational speed. In the same vein, the above biological distinctions may enable plausible personal genetic manipulation.

[chris3721]

Might be related;

I figured this could offer an empirical answer to the question, "Do women like big dicks?" Hint; it's due to evolution.

Penis size interacts with body shape and height to influence male attractiveness


Abstract

Compelling evidence from many animal taxa indicates that male genitalia are often under postcopulatory sexual selection for characteristics that increase a male’s relative fertilization success. There could, however, also be direct precopulatory female mate choice based on male genital traits. Before clothing, the nonretractable human penis would have been conspicuous to potential mates. This observation has generated suggestions that human penis size partly evolved because of female choice. Here we show, based upon female assessment of digitally projected life-size, computer-generated images, that penis size interacts with body shape and height to determine male sexual attractiveness. Positive linear selection was detected for penis size, but the marginal increase in attractiveness eventually declined with greater penis size (i.e., quadratic selection). Penis size had a stronger effect on attractiveness in taller men than in shorter men. There was a similar increase in the positive effect of penis size on attractiveness with a more masculine body shape (i.e., greater shoulder-to-hip ratio). Surprisingly, larger penis size and greater height had almost equivalent positive effects on male attractiveness. Our results support the hypothesis that female mate choice could have driven the evolution of larger penises in humans. More broadly, our results show that precopulatory sexual selection can play a role in the evolution of genital traits.

Here are some reports of this study in the media that goes into it in more detail than the abstract.

Rob Brooks: Penis Size May Be Driven By Women (Oh, and It Matters)

and

Penis Size Matters, Study Says - Australian Popular Science | Australian Popular Science

[CUSP82]

If evolution preferred big dicks why aren't our dicks attached to our foreheads so that our female mate could choose and therefore all the guys with small dicks would be dead by now. Don't you all think that evolution has changed a bit since Darwin did his thing?

[Jm123]

If evolution preferred big dicks why aren't our dicks attached to our foreheads so that our female mate could choose and therefore all the guys with small dicks would be dead by now. Don't you all think that evolution has changed a bit since Darwin did his thing?

Completely agree. Research has indicated that environmental factors, may be a very large factor in penis size. In addition, just because a big dick may feel better to a woman, does not mean it is better at getting her pregnant. Humans do have substantially larger dicks proportionally speaking, and we crush all other primates. Therefore it would be reasonable to think that there was/is an upward pressure on dick size in our past, however, that does not mean it still is occurring.

[CUSP82]

Evolution, nature, is not at all concerned with the female orgasm. That where you guys are making your mistake. Did you ever watch cats fuck? If you haven't well it's not such a good thing for the female. Nature is concerned about reproduction and a man can reproduce if he has a one inch dick. If nature, eveolution, cared about a womans orgasm then our dicks would be on our heads, we'd have no tongue, and the marital aid stores wouldn't exist.

[Jm123]

Evolution, nature, is not at all concerned with the female orgasm. That where you guys are making your mistake. Did you ever watch cats fuck? If you haven't well it's not such a good thing for the female. Nature is concerned about reproduction and a man can reproduce if he has a one inch dick. If nature, eveolution, cared about a womans orgasm then our dicks would be on our heads, we'd have no tongue, and the marital aid stores wouldn't exist.

Just to give you a slightly different view here is a quote from wiki (talk about a cluster fuck). However, honestly, I would agree with you that evolution is not a major talking point concerning our current dick sizes. I believe environmental factors play a much larger role/concern for the modern man.

"The Lake Duck lives in Argentina, Chile, Paraguay, and Brazil in southern South America.[1]

It is notable for possessing, in relation to body length, the longest penis of all vertebrates; the penis, which is typically coiled up in flaccid state, can reach about the same length as the animal itself when fully erect, but more commonly is about half the bird's length.[2][3] It is theorized that the remarkable size of their spiny penises with bristled tips may have evolved in response to competitive pressure in these highly promiscuous birds, removing sperm from previous matings in the manner of a bottle brush.

Although most male birds have no penis,[4] ducks have a long corkscrew penis, and the females have a long corkscrew vagina, which spirals in the opposite direction.[5] The males often try to force copulation, but the complex mating geometry allows the females to retain control—most forced copulations do not result in successful fertilisation.[6]
"

[Ivor]

I think it's worth noting that we live in a dick-size-obsessed culture (hence this forum, amongst others), but it's not justified to assume that all other cultures at all times and in all parts of the world have had the same obsession. The ancient Greeks and Romans famously found large penises bestial, comical and grotesque, and considered a small penis to be aesthetically ideal. I mean look at Michaelangelo's 'David', which was made in the Renaissance but is modelled after originals from Classical antiquity. And there's a line in the Kama Sutra describing the ideal penis as thick but short - in fact I think it even describes men with long penises as 'cursed'!

So just because, in Europe and North America in the 21st century, men want to have massive dicks and (some) women want men with massive dicks, doesn't mean it's always been like that. If it had always been that way, penises would soon become too big even for sex to be practically possible - the peacock's tail effect - and that would obviously be pretty self-defeating in evolutionary terms. Remember also that a very big dick is no better than an average-sized one for impregnating a woman, and that a lot of women find very big dicks simply painful rather than arousing. Even those that like the look of a huge wang or the feel of it in their hands don't necessarily want it tearing them up.

[ThinkBigThoughts]

I think it's worth noting that we live in a dick-size-obsessed culture (hence this forum, amongst others), but it's not justified to assume that all other cultures at all times and in all parts of the world have had the same obsession. The ancient Greeks and Romans famously found large penises bestial, comical and grotesque, and considered a small penis to be aesthetically ideal. I mean look at Michaelangelo's 'David', which was made in the Renaissance but is modelled after originals from Classical antiquity.

I was in the Louvre not too long ago and found it interesting that of all the nude male sculpture, not one of those stony dicks was bigger than my little fella lol. Of course I was also in a shop in Seattle once that had a sperm whale penis on display, that damn thing was taller than I am!