Comments on: If opposites attract, why is my sister so pretty?

By: Richard Gadsden

Richard Gadsden — Mon, 09 Dec 2013 16:05:02 +0000

I’ve seen – probably on hbdchick – that peak fertility is with third cousins.

And that strongly endogamous populations (ie where you never marry / mate with anyone outside the group) average out as third cousins to each other.

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By: Rob

Rob — Thu, 04 Apr 2013 16:14:33 +0000

I may regret asking this, but when are you assessing people’s sexiness by touching them without having seen them?

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By: nydwracu

nydwracu — Wed, 27 Mar 2013 13:35:53 +0000

The idea that people are attracted to genetic similarity in general seems really weird to me; I have an abnormally large and diverse social network and have never dated a girl of my… er, subrace? (Out of the ones I’ve even considered dating, only one (out of only four white girls) had substantial Western European ancestry; of the other three, one was Italian and two were Jewish.)

The observed tendency toward spousal genetic similarity seems like it can be explained in terms of 1. geographic proximity -> genetic similarity and 2. genetic influence in behavior leading toward people with enough shared interests, behavior patterns, etc. to get along well being more genetically similar than the average for the village or whatever, with the motivator being not genetic similarity on a subconscious level but behavioral or thedish similarity on a mostly-conscious level. (Or perhaps subconscious-level genetic similarity-judging processes motivate initial judgments of physical attraction and those results are refined later by mostly-conscious-level judgments of behavioral/thedish similarity…?)

Do people with more diverse social networks (people in cities, say) end up with less genetically similar spouses? How does that number compare to the level that would be predicted by chance?

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By: Cereus

Cereus — Tue, 26 Mar 2013 18:44:03 +0000

Another reason for the attraction to similar people –

In general, we don’t just mate with people and then walk away and never talk to them again. We *typically* have some sort of relationship with them and watch out for any kids we might have (and watch out for eachother). So it would make sense to be with someone that is coming from enough of the same perspective that the two of you can communicate and work as a team well.

Of course different people can make a good team because they have different strengths, but if you’re very different it takes a lot of effort just to figure out what you’re going to be doing and make sure you’re on the same page. So there’s advantages and disadvantages.

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By: Nestor

Nestor — Sun, 24 Mar 2013 00:33:48 +0000

It arises because siblings find each other attractive without it, which causes problems, which select for the Westermark effect without weakening the histocompatibility attraction function.

Think of it as a patch.

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By: Kevin

Kevin — Sat, 23 Mar 2013 20:31:41 +0000

For any given personality, the set of similar personalities and the set of compatible are not necessarily identical, and may not even have significant overlap.

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By: Nestor

Nestor — Sat, 23 Mar 2013 18:29:01 +0000

The lectures are here, the cousin thing was in the 3rd or 4th video, iirc

http://www.youtube.com/watch?v=NNnIGh9g6fA&list=EC848F2368C90DDC3D

But in a modern context at least, transplants can be hard to come by for people with very mixed parentage.

Not all recessive genes are bad, and losing the traits connected with them might be a bad idea in some contexts. I hear in the UK they have cases of rickets again in dark skinned kids.

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By: AphroditeGoneAwry

AphroditeGoneAwry — Sat, 23 Mar 2013 17:09:48 +0000

Yeah. This is much what I think.

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By: AphroditeGoneAwry

AphroditeGoneAwry — Sat, 23 Mar 2013 16:27:38 +0000

It makes sense (regarding your last paragraph), because nature needs to fall somewhere in the middle, or closer to consanguinity; protecting that genes are not too heterogeneous to avoid genetic incompatibilities in offspring, but yet bolster the beneficial similarities that can result by doing that, like intelligence and attractiveness.

The fact that siblings separated at birth are likely to be sexually attracted to each other might hint that some dysfunction in the MHC mechanism occurs when siblings are not reared together, implying an environmental influence at play in its development.

Perhaps the best blending is somewhere between distant cousins, as what you might get with extended tribe interaction. Historically, tribes have always done this; come together once a year to meet and forge alliances, but also romantic and sexual interaction between members.

I’d say that is likely the best mix possible. And it appears that anecdotally, historically, and scientifically (thanks to your awesome article synopsis) that is supported.

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By: xor

xor — Sat, 23 Mar 2013 09:58:00 +0000

“the top 0.01% of the population for similarity to me” <– memetically similar, not genetically (though they may be somewhat correlated)

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