I just realized that since homosexuality is mildly heritable, a lack of socially-imposed marriage customs, brought about by political empowerment of homosexuals, could actually (mildly) reduce the number of homosexuals.
Homosexuals are still interested in bearing and raising children. In a permissive political and social climate, with same-sex marriage, they can use surrogate mothers. Lesbians can, of course, bear their own children.
We are discussing the dynamics of genes. If the gene has low fitness, it will be purged from the population and the rate of homosexuality will decline, even if the grandparents have full fitness. By using a donor, we are re-randomizing. Instead of a parent with the gene, we are replacing with a parent with a 50% chance of having the gene.
Similarly, what if two people with achondroplasia have children, repeatedly, until 2 survive infancy. Then the parents have fitness 1, but 1⁄4 of their children were homozygous and died in infancy. Their children are uniformly drawn from the remaining 3 children, consisting of 2 heterozygous, 1 homozygous normal. So the gene frequency has gone down from 1⁄2 in the parents to 1⁄3 in children. The parents have full fitness, but the gene has fitness only 2⁄3.
I don’t actually know if they do or not, but why don’t more people do that? Maybe they’re afraid the donors will expect or demand some rights or involvement in the child’s life, which isn’t a problem with anonymous or hired donors.
Agreed regarding the fitness cost. That makes chaosmage’s comment correct, although I didn’t realize it at first; his comparison with asexuals led to me to think his proposed mechanism was simply homosexuals raising fewer children, whether their own or not.
You might as well ask why people adopt strangers as ask why they half-adopt by using strangers as donors. The answer is that people are adaptation-executors, not deliberate fitness maximizers.
I hear about people asking for donations from friends more than family, which seems to me to be a bigger risk. Being on bad terms with family because of orientation probably is a reason, though.
People have always sometimes adopted the children of near relatives who couldn’t care for them, at much higher rates than adopting strangers; that’s fitness increasing. It’s not a stretch to imagine that crossing over to sperm and egg donations.
Both friends and family have the large advantage (at least I imagine it to be so) that they are known quantities: you know them well and can evaluate them as biological parents just as you would a potential mate. I wonder why sperm banks don’t seem to offer the sperm of people with known qualities at higher prices: not just screened for diseases, but known to have strong positive traits like good looks and intelligence.
Surrogate mothers don’t one of the people in a gay couple more of a father than the other person. That’s not necessarily desirable to a gay couple. Adopting children might be a more straightforward solution if the society makes it easy for homosexuals to adopt.
It’s not clear that making none of the two men a father is better (i.e. more desirable to them) than making just one a father. They could each father one of two children, for instance.
If they are married, such concerns would only come up in a divorce. Child custody battles are weird and ugly enough in heterosexual marriages; I don’t know what they would look like in homosexual ones.
Also, even the man who is not a father may still consider it a better choice. Just as some heterosexual couples one of whom is infertile may prefer a surrogate mother or the sperm bank to adoption.
Legal rights aren’t the only that matter. Raising children means that you have to make a lot of parenting decisions. If one partner feels that he has more right to influence those decisions that’s an issue.
I’ll take your word for it. I’ve never been in that situation and don’t have any instincts for how it might feel. It might also be relevant that the other partner might want to invest fewer resources in the child because it’s not biologically theirs.
That’s funny.
I just realized that since homosexuality is mildly heritable, a lack of socially-imposed marriage customs, brought about by political empowerment of homosexuals, could actually (mildly) reduce the number of homosexuals.
I wonder if the same is true for asexuals.
Homosexuals are still interested in bearing and raising children. In a permissive political and social climate, with same-sex marriage, they can use surrogate mothers. Lesbians can, of course, bear their own children.
Using sperm or egg donors is a 50% fitness cost. (adopting is 100% fitness cost)
That’s true, although they could improve that by asking their parents or siblings to be donors.
But they don’t. Anyhow, that’s still a 25% fitness cost, which is huge.
From the perspective of the parents of the gay couple, it’s a 0% fitness cost, though.
Irrelevant.
We are discussing the dynamics of genes. If the gene has low fitness, it will be purged from the population and the rate of homosexuality will decline, even if the grandparents have full fitness. By using a donor, we are re-randomizing. Instead of a parent with the gene, we are replacing with a parent with a 50% chance of having the gene.
Similarly, what if two people with achondroplasia have children, repeatedly, until 2 survive infancy. Then the parents have fitness 1, but 1⁄4 of their children were homozygous and died in infancy. Their children are uniformly drawn from the remaining 3 children, consisting of 2 heterozygous, 1 homozygous normal. So the gene frequency has gone down from 1⁄2 in the parents to 1⁄3 in children. The parents have full fitness, but the gene has fitness only 2⁄3.
I don’t actually know if they do or not, but why don’t more people do that? Maybe they’re afraid the donors will expect or demand some rights or involvement in the child’s life, which isn’t a problem with anonymous or hired donors.
Agreed regarding the fitness cost. That makes chaosmage’s comment correct, although I didn’t realize it at first; his comparison with asexuals led to me to think his proposed mechanism was simply homosexuals raising fewer children, whether their own or not.
You might as well ask why people adopt strangers as ask why they half-adopt by using strangers as donors. The answer is that people are adaptation-executors, not deliberate fitness maximizers.
I hear about people asking for donations from friends more than family, which seems to me to be a bigger risk. Being on bad terms with family because of orientation probably is a reason, though.
People have always sometimes adopted the children of near relatives who couldn’t care for them, at much higher rates than adopting strangers; that’s fitness increasing. It’s not a stretch to imagine that crossing over to sperm and egg donations.
Both friends and family have the large advantage (at least I imagine it to be so) that they are known quantities: you know them well and can evaluate them as biological parents just as you would a potential mate. I wonder why sperm banks don’t seem to offer the sperm of people with known qualities at higher prices: not just screened for diseases, but known to have strong positive traits like good looks and intelligence.
Incest is bad, and their children would be unhealthy and retarded.
No, you use one partner, and sperm or egg from a relative of the other partner.
Ok, well that works.
Surrogate mothers don’t one of the people in a gay couple more of a father than the other person. That’s not necessarily desirable to a gay couple. Adopting children might be a more straightforward solution if the society makes it easy for homosexuals to adopt.
It’s not clear that making none of the two men a father is better (i.e. more desirable to them) than making just one a father. They could each father one of two children, for instance.
If one is a father there are concerns about that person having more rights about determining the fate of the child then the other partner.
If they are married, such concerns would only come up in a divorce. Child custody battles are weird and ugly enough in heterosexual marriages; I don’t know what they would look like in homosexual ones.
Also, even the man who is not a father may still consider it a better choice. Just as some heterosexual couples one of whom is infertile may prefer a surrogate mother or the sperm bank to adoption.
Legal rights aren’t the only that matter. Raising children means that you have to make a lot of parenting decisions. If one partner feels that he has more right to influence those decisions that’s an issue.
I’ll take your word for it. I’ve never been in that situation and don’t have any instincts for how it might feel. It might also be relevant that the other partner might want to invest fewer resources in the child because it’s not biologically theirs.