Why is it that all kinds of societies have restrictions on relatives one can marry?

Question

I know it produces flawed offspring.

What about non-procreative incest? What are the reasons that is still taboo?

Why does the incest taboo exist in all cultures?

Answer 1

Most of modern reasoning is for genetics and trying not to match up bad traits  But I think it actually goes deeper into our core.  I saw a program one time on a gorilla being taught to us hand signals to talk with her keeps.  She got quite good at answering questions and even asking for things she wanted.  They got her a male companion when she was young thinking that when they grew up the two would mate.  But the two gorilla never would mate.  When asked if she would like a mate, she agreed and did some shopping on-line with her keeper for a mate.  They ask her why she didn't want her lifetime companion as a mate and she referred to him as her brother.  And she could not mate with her brother. Now that information came from a gorilla.  Very interesting

Answer 2

Repulsion from incestual relationships is likely an evolved trait since it is found in MANY animals. For instance, gorillas tend to live in groups with only one male who will impregnate all females, except his daughters.

The disadvantage of familial mating is obvious: there is an increased frequency of the same types of deleterious alleles that leads to children who die.

Answer 3

wow... you are beasting with the incest right now

Answer 4

The incest taboo goes hand in hand with how a society organizes kinship structures.  In some cultures, for example, it might be taboo or incestuous to marry your uncle's son on your mother's side, but not your aunt's son.  Finding someone appropriate for marriage can help cement political ties, among other things.  Even in the example of ancient Egyptians, it was royalty that would marry a brother or sister, while common folks might marry an uncle or niece and leave it at that.

Primates of many kinds also show signs of having taboos on incest, so it is likely a trait that we as humans have had for, well, I would think as long as we've been human!

Incest taboos consist of written and unwritten rules.  It's illegal to marry someone related to you by blood for example, but if someone (such as yourself) asks questions about incest people have a visceral reaction; which is the unwritten portion.  What exactly makes for an incestuous relationship is by and large mostly cultural.

There is also some debate over whether the incest taboo is universal; since kinship is determined culturally, there are different ideas about who it is ok to marry and who isn't.  The incest taboo itself is more fluid than Western people are often aware.  There are many examples in history of people marrying their brothers, fathers, sisters and mothers.

I'm sorry, this doesn't even begin to cover the explanation!   But, my answer is already getting too long, even for me!  Good question tho.

EDIT:  Se also the Westermarck effect.

Answer 5

taboo or not, little girls today still get raped by dad, uncle and brother...ect..do you think perhaps it is the women who finds it taboo??  or that loss of self control or lack of boundaries that causes chaos could make it taboo??? I'm not really sure why its  taboo ,when it become so, only when someone gets caught, or brings the act into exposure..in a consensual act would it be any different??? more so because it is receptive to both parties involved in the act..good question...

Answer 6

Because historically people could not travel far away from home so the choices of mates were limited.  It was well considered that somewhere, down the line, you would be related.  They put restrictions on how close you were because of a number of reasons, including genetics and religion and social reasons.

It does not "produce flawed off spring".  What it does is eliminate possible genes that could eliminate bad traits.  If two people are from the same family and each are more likely to share a similar passive trait which is a genetic disease.  Thus if they mated there is a twice as likely chance the child will get it, vs. if they would have mated with someone who was not a carrier.  The chances would have been diluted.  This problem has historically happen to the Hebrews and modern day Amish.

You can mate with a close relative and have the child turn out perfectly normal – however, that being said, there is a chance for the above to occur.

Answer 7

Well it's taboo for the same reason homosexuality is: the bible condemned people to death for incest, and homosexuality.

I, personally, thinks it's horrible. There is absolutely NOTHING wrong with incest. However, I am against relatives having children, for the sake of the children.

Answer 8

In some eastern cultures, still today it is preferred to marry a first cousin. The reason is to keep the money in the family.

Answer 9

If you marry a close relative, those little problems that are recessive genes have a better chance of coming out in your children.  Most cultures always have approved of marriages or s*x that improves the general strength of the gene pool.  They may not have know about genes but they certainly knew it produced idiots and handicaps and now that we know about recessive bad traits, there should be NO reason to want to marry that close relative.  That is unless you're an idiot and further proof of inbreeding. . .

Answer 10

Well, it didn't always exist for all cultures and ranks in society.

The Ptolomies in Egypt, as did their Egyptian predecessors often married their sisters; Cleopatra was married to 2 of her brothers before Mark Antony.  In that case, it was to preserve the blood purity of the Royal line.

I think the main reason why its repulsive is one of cultural bias; but it does serve an evolutionary purpose- you get a much better society genetically speaking with people who aren't related to each other having kids.

Answer 11

Because that's disgusting.