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> Another may be to prevent excess breeding by an individual, which may reduce genetic diversity. That sounds like group selectionism. In what circumstance wou

> Another may be to prevent excess breeding by an individual, which may reduce genetic diversity. That sounds like group selectionism. In what circumstance would this be deleterious to the propagation of that individual's genes?

reason-mr 6y ago
Surely if genetic variation is introduced primarily by the breeding process, any factors which have a effect against like (competing for food, less genetic variation), etc, are going to get selected against? I have always thought this was the reason behind human lifespans - in neolithic times, up to 33 years. Just enough time to mate and raise another individual to maturity.
- jacobush 6y ago
  No, medium 33, some could get old. Just not most. And median and medium got dragged by high child mortality.
  - dash2 6y ago
    What is "medium"? I know median and mean.
    - jacobush 6y ago
      Ok, that's just mean. Medium I mean, in my native language, is mean.
MayeulC 6y ago
Lesser genetic diversity is always bad for survival: with clonal species like the bananas we cultivate, for instance, a single pathogen can endanger the whole population. The less diverse the population, the less likely timely mutations will help protect it. Incidentally, our modern society is pretty diverse, especially as we protect those who couldn't otherwise survive without modern medicine.
- jbay808 6y ago
  No disagreements there, but adaptations that are advantageous for the population as a whole won't necessarily spread through a population. https://www.lesswrong.com/posts/QsMJQSFj7WfoTMNgW/the-tragedy-of-group-selectionism https://www.lesswrong.com/posts/QsMJQSFj7WfoTMNgW/the-traged...
  - MayeulC 6y ago
    Ah, I better see your point. Well, that adaptation has to be selected for at some point of course. Among a single species, with a 50/50 split of a genetically diverse and homogeneous population, if you eliminate 10% of the former and 75% of the latter, the split becomes 80/20. If that distinction stemmed from genetic factors, you have selected for diversity. Genetic diversity isn't only advantageous to the population. It's advantageous for the individuals that carry it, depending on the circumstances. Therefore it can easily be selected for.

reason-mr 6y ago

Surely if genetic variation is introduced primarily by the breeding process, any factors which have a effect against like (competing for food, less genetic variation), etc, are going to get selected against? I have always thought this was the reason behind human lifespans - in neolithic times, up to 33 years. Just enough time to mate and raise another individual to maturity.

jacobush 6y ago
No, medium 33, some could get old. Just not most. And median and medium got dragged by high child mortality.
- dash2 6y ago
  What is "medium"? I know median and mean.
  - jacobush 6y ago
    Ok, that's just mean. Medium I mean, in my native language, is mean.

MayeulC 6y ago

Lesser genetic diversity is always bad for survival: with clonal species like the bananas we cultivate, for instance, a single pathogen can endanger the whole population. The less diverse the population, the less likely timely mutations will help protect it. Incidentally, our modern society is pretty diverse, especially as we protect those who couldn't otherwise survive without modern medicine.

jbay808 6y ago
No disagreements there, but adaptations that are advantageous for the population as a whole won't necessarily spread through a population. https://www.lesswrong.com/posts/QsMJQSFj7WfoTMNgW/the-tragedy-of-group-selectionism https://www.lesswrong.com/posts/QsMJQSFj7WfoTMNgW/the-traged...
- MayeulC 6y ago
  Ah, I better see your point. Well, that adaptation has to be selected for at some point of course. Among a single species, with a 50/50 split of a genetically diverse and homogeneous population, if you eliminate 10% of the former and 75% of the latter, the split becomes 80/20. If that distinction stemmed from genetic factors, you have selected for diversity. Genetic diversity isn't only advantageous to the population. It's advantageous for the individuals that carry it, depending on the circumstances. Therefore it can easily be selected for.