[Igor Antunov]

Researchers said that elder girls were more likely to take on the role of helping with family chores and as a result were less likely to form sexual relationships.

"Reports of daughters helping parents are common," study authors Fritha Milne and Debra Judge, of Western Australia University.

"Elder daughters may provide more help to their parents in raising their younger brothers than do elder brothers.

"Associated with this prolonged help is a delay in sexual activity and thus a delay in potential for starting their own family."

The researchers studied 273 people aged 18 to 75 and found girls with exclusively elder brothers were almost a year older when they had their first period than those with no older siblings or those with only elder sisters.

And girls with only younger brothers were on average almost two years older when they first had sex than those with no younger siblings.

The findings were published in Proceedings of the Royal Society B.

http://www.telegraph.co.uk/science/scie ... onger.html

Makes sense.

More detailed article: http://www.abc.net.au/news/stories/2010 ... 986065.htm

[lovertothemoon]

Yet another thing to blame my little brother on!

But my query would be why is it brothers specifically? What about having younger brothers is any different than younger sisters, especially considering the reasons given is the fact that older girls are trained to take care of the younger children?

[Igor Antunov]

Maybe younger sisters behave differently and don't require as much supervision.

[Riza]

I don't think, personally, that what their saying about the younger brother stuff is true. i think that has nothing to do with their older sisters and the age they become sexually active. Yes, they do lend a hand in the raising of the younger brother, but i don't think that stops them from being sexually active. I was brought up in a single parent home, with a lil brother. I dont think my helping with him prolonged me from being sexually active. And believe this for most cases. And like it was pointed out about lil sisters as well. Considering they say it doesn't affect the same way, I still believe it would make no difference either way.

[Nandi]

From an evolutionary paradigma this shouldn't be too hard to unravel.

Firstly, why would a gene delay reproductivity in an under normal circumstances sexually ripe female? For females this is especially disturbing since their reproductive value greatly diminishes with age. Seemingly the advantages of that delayed sexual capability, helping one's siblings survive who'm they share on average half their genes with, outweigh the opportunity costs of it, the diminished reproductive length of time and desireability on the market.

Secondly, why would this effect only be discernible in the relationship older sister - younger brother? This is less straightforward. I'm guessing it has to do with the waterfall-effect of male reproductivity. A succesful male, if he survives infancy, can have overwhelming succes procreating and spreading his genes. The minimal investment demanded from the older sister, a year's worth of sexual retardation or on average one child, would be sufficiently counter-acted by a higher survival chance of any male sibling who, if he reaches sexual maturity, could reproduce much more then the one child sacrificed by the older sister. Research has shown older, unattractive females with little reproductive potential will often dedicate their lives to their sibling's offspring. From a gene's point of view this makes perfect sense; the gene has more succes in multiplying itself by caring for their sibling's children they share on average 1/8th of their genes with than actually sexually reproducing itself.

[Riza]

Sorry to say but i really don't agree with this. All the research inthe world could not convince me other wise. Im a product of this particular theory not working and believe that the money being used to research this particular issue is a waste of time and money.

[Ter]

I heard that in places like Arkansas, it doesn't matter if the brothers are older or younger. The girls who can run faster stay virgin.


Ter

[Decky]

Sorry to say but i really don't agree with this. All the research inthe world could not convince me other wise.

What have you got against reserch?

Im a product of this particular theory not working

More likely does not mean that it happens in every circumstance.

and believe that the money being used to research this particular issue is a waste of time and money.

Couldn't agree with you more.

[Nets]

[Mod Note: Moved to Sociology]

[eugenekop]

and believe that the money being used to research this particular issue is a waste of time and money.

Like 95% of the researches. Really, someone should start firing these fools. Its amazing how much tax money goes on these useless people with their useless theories.

[Lightman]

Sorry to say but i really don't agree with this. All the research inthe world could not convince me other wise. Im a product of this particular theory not working and believe that the money being used to research this particular issue is a waste of time and money.

Of course there are anecdotal exceptions. Nobody is making a sweeping generalization that all women with younger brothers wait longer to have sex; they are merely making the statement that a woman with a younger brother is more likely to wait longer. This is not a matter of opinion, assuming that the methodology of this study was appropriately rigorous.

[Bella]

I am the eldest

I think the eldest children are more responsible and mature faster. It doesn't matter whether the younger siblings are male or female or both. You can tell when a person is the youngest or an only child. They're impulsive and spoiled and more likely to act recklessly.

[Thunderhawk]

Could it be something as simple as brother(s) scaring off potential suitors?

With older brother(s) consuming less of their younger sister's time and having less time and desire themselves to protect their sister's virginity?

[franfran]

Could it just simply be that the experience of baby-sitting young boys is enough to put anyone off having children?

[franfran]

And what about only children? Do they lose their virginity later than anyone else because of their inherent lack of social interaction, or are they first off the rank because there's nothing to hold them back?

[Suska]

probably has something to do with incest aversion

[franfran]

probably has something to do with incest aversion

Yuck. Sort of makes me glad that I don't have any brothers.........................

[Suska]

Incest aversion is very natural, basically it entails people not being at all attracted to other people they grow up with. They needn't be blood related, this has been demonstrated fairly well statistically. Not sure why that by itself would be icky, or why it would cause a latency in sexual interest in the case given, but it stands to reason simply by being influential in the factors here.

[QatzelOk]

Incest aversion is very natural, basically it entails people not being at all attracted to other people they grow up with.

You haven't demonstrated the unnaturalness of incest at all.

Instead, you have provided rationalizations for what is possibly a social construct.

Can you possibly explain why incest has faded from our evolving human genetic codes?

[Suska]

I don't need to demonstrate anything. By natural I mean evolutionary. It's a genetic sanitation habit we probably picked up over 2 million years ago.

Fuck it fine, you got me... even gravity is a social construct...