Could excess prolificity/offspring be maladaptive? (nurturance distribution)

[MonDie]

When I was thinking about sexuality as an adaptation, I wondered whether excessive tendencies toward heterosexuality could be maladaptive, especially for species that put a great amount of nurturance into their offspring.

 

If a female mammal is producing too many offspring, she'll probably invest less into each offspring. At what point does this become maladaptive? If it becomes maladaptive, she might stop caring for some of the offspring, but that doesn't undo the initial investment during pregnancy.

 

Anyway, the two main explanations for genetic male homosexuality seem to be:

• the kin-selection explanation—homosexual men help care for related offspring
• the sexually antagonistic selection explanation—their female relatives tend to be unusually prolific

This nurturance distribution idea would fill a gap. The combination of these three ideas would suggest an economical system that sustains genes that may make either sex androphilic.

Edited December 14, 2012 by Mondays Assignment: Die

[Delta1212]

It becomes maladaptive at the point where fewer children ultimately survive to reproduce. This number will vary between species based on how much care the parent is capable of providing overall, and how much care the offspring require to have a reasonable chance of survival.

 

I'm not really clear on how this relates to homosexuality, however.

[MonDie]

I'm not really clear on how this relates to homosexuality, however.

 

Androphilia = love of men

 

The sexually antagonistic selection explanation for male homosexuality is that there are genes for androphilia which appear in both males and females. Even though the men with these androphilia genes produce less offspring, the females with these genes produce more offspring, thus the genes remain in the gene pool. Researchers have found evidence for this in Italian families.

If this is the case, the females who are more prolific (producing more offspring) might actually need their male relatives to be homosexual, because that means they have child-rearing helpers. If their male relatives were heterosexuals with children of their own, these prolific women might not have enough resources to support all the children they produce.

Albeit, the effectiveness of this hypothetical system would depend on certain cultural variables, i.e. matrilocality, or something similar.

Edited December 19, 2012 by Mondays Assignment: Die

[Delta1212]

 

Androphilia = love of men

 

The sexually antagonistic selection explanation for male homosexuality is that there are genes for androphilia which appear in both males and females. Even though the men with these androphilia genes produce less offspring, the females with these genes produce more offspring, thus the genes remain in the gene pool. Researchers have found evidence for this in Italian families.

If this is the case, the females who are more prolific (producing more offspring) might actually need their male relatives to be homosexual, because that means they have child-rearing helpers. If their male relatives were heterosexuals with children of their own, these prolific women might not have enough resources to support all the children they produce.

Albeit, the effectiveness of this hypothetical system would depend on certain cultural variables, i.e. matrilocality, or something similar.

 

Ah, I see. I understood (and was familiar with) the two hypotheses, but hadn't seen the connection you were making between them.