5 ms·

If it was advantageous for us to have lots of children, then women would have a dozen at a time, rather than one. There are plenty of mammals that do that. Ther

by maratd 7y ago

If it was advantageous for us to have lots of children, then women would have a dozen at a time, rather than one. There are plenty of mammals that do that. There’s clearly a tradeoff there and the selective pressures for humans tend to lean toward fewer. Not sure where we’ll end up, but time will tell.

bin0 7y ago
I think there was such a selection pressure when we were nomadic hunter-gatherers. Agriculture is a very recent development anthropologically, so we were still in the mode of one-kid-per-pregnancy, though multiple might have been advantageous. It's possible we developed higher fertility due to that, but we didn't have enough time for that new pressure to kick in.
- barry-cotter 7y ago
  It’s been 5,000 years since the dawn of agriculture. If multiple births were fertility increasing they’d be, if not normal, at least common in some groups. You don’t even get 1 in 3. Single births are clearly not being found wanting by the Blind Idiot God.
  - bin0 7y ago
    Not necessarily. Mortality of mothers is higher in multiple births; maybe that's a counter-pressure (fewer children). Children do worse as well ([0], [1], [2]). Ladies are not built to carry more than one child, especially considering the size of our children, and agriculture has been such a blip on the evolutionary/anthropological timescale that we have not had time to evolve so significantly as to change our basic reproduction. [0]: https://watermark.silverchair.com/151663.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAkMwggI_BgkqhkiG9w0BBwagggIwMIICLAIBADCCAiUGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMNDbyu9VK0lVH1VRPAgEQgIIB9nVdpx5WY2VFTM3siR6zUpI0NIrJ8G9sLgHflEENvKJn66C3kpwvmovR88zIGT4Zf1EjM37ovBkwyBefyQUyxX2tV9MlM9OHvTxWrEG41Otg_iehqYE75eFXqRmaREkeDxT_ISS78RZiRXb-i6WkAIIleISQsmOwkTX_aGVOTOkFKNtHYQXN69Db-DMkH_Qh_wtjf6TLPgDfnShgZ8_YwcfGThvT1EwSpazZAHxh82Bfn8zKsfuwaEsObTJsVAuYACQcigL0RYheX7RHBn42fW2eq6IdG6702SQWhlpEfeTuez0kPQ-r-Jh44nomPMhRLMZMtXrtYVkXfDFCs3m1le7xk9YLjvNKZDdJ-LvJwtp9ouuvl1cQajuaSPN6VI5sD2SjGkd5NDs1CAaODx9hwmhKL-6S_WyMlktkw9keaDWvnIRyjLjiTO1AOHs_eURKqxutChnO9xeQYOwKjgJBrT5vt9hMPao9Weab89ykbOwiApEo4NGBAxHY4PGdgm8K_1O8N18g_De-fFCTeY7gMp0OYbWDAxEMRLrKNdTl1ON9sAU488gm7D6FHCQ71yPmc5ucl_aVoTm4sb85QLxJykbamXeBKCIr40bB_0M59bG37P1swc6dWvojGic6c5Vqr9HwB-ItUGp8afq2_zBBOMBTV7Ih4FU https://watermark.silverchair.com/151663.pdf?token=AQECAHi20... [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541191/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541191/ [2] https://bmjopen.bmj.com/content/4/4/e004514 https://bmjopen.bmj.com/content/4/4/e004514
option_greek 7y ago
Minor correction: Advantageous to the children (conferring evolutionary advantage). Not to us.
- maratd 7y ago
  I'm not sure I understand your distinction. From a gene-based perspective, the gene, whether in the child or in the parent, is the same. The selection pressure is on a gene level, not on a species or individual level.
malvosenior 7y ago
The size of the human brain makes this physically impossible.
- maratd 7y ago
  Ok, explain triplets. https://en.wikipedia.org/wiki/Multiple_birth https://en.wikipedia.org/wiki/Multiple_birth
  - malvosenior 7y ago
    Three and twelve are very different from each other. Even three is very rare and often comes with complications.

by maratd 7y ago

bin0 7y ago

I think there was such a selection pressure when we were nomadic hunter-gatherers. Agriculture is a very recent development anthropologically, so we were still in the mode of one-kid-per-pregnancy, though multiple might have been advantageous. It's possible we developed higher fertility due to that, but we didn't have enough time for that new pressure to kick in.

barry-cotter 7y ago
It’s been 5,000 years since the dawn of agriculture. If multiple births were fertility increasing they’d be, if not normal, at least common in some groups. You don’t even get 1 in 3. Single births are clearly not being found wanting by the Blind Idiot God.
- bin0 7y ago
  Not necessarily. Mortality of mothers is higher in multiple births; maybe that's a counter-pressure (fewer children). Children do worse as well ([0], [1], [2]). Ladies are not built to carry more than one child, especially considering the size of our children, and agriculture has been such a blip on the evolutionary/anthropological timescale that we have not had time to evolve so significantly as to change our basic reproduction. [0]: https://watermark.silverchair.com/151663.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAkMwggI_BgkqhkiG9w0BBwagggIwMIICLAIBADCCAiUGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMNDbyu9VK0lVH1VRPAgEQgIIB9nVdpx5WY2VFTM3siR6zUpI0NIrJ8G9sLgHflEENvKJn66C3kpwvmovR88zIGT4Zf1EjM37ovBkwyBefyQUyxX2tV9MlM9OHvTxWrEG41Otg_iehqYE75eFXqRmaREkeDxT_ISS78RZiRXb-i6WkAIIleISQsmOwkTX_aGVOTOkFKNtHYQXN69Db-DMkH_Qh_wtjf6TLPgDfnShgZ8_YwcfGThvT1EwSpazZAHxh82Bfn8zKsfuwaEsObTJsVAuYACQcigL0RYheX7RHBn42fW2eq6IdG6702SQWhlpEfeTuez0kPQ-r-Jh44nomPMhRLMZMtXrtYVkXfDFCs3m1le7xk9YLjvNKZDdJ-LvJwtp9ouuvl1cQajuaSPN6VI5sD2SjGkd5NDs1CAaODx9hwmhKL-6S_WyMlktkw9keaDWvnIRyjLjiTO1AOHs_eURKqxutChnO9xeQYOwKjgJBrT5vt9hMPao9Weab89ykbOwiApEo4NGBAxHY4PGdgm8K_1O8N18g_De-fFCTeY7gMp0OYbWDAxEMRLrKNdTl1ON9sAU488gm7D6FHCQ71yPmc5ucl_aVoTm4sb85QLxJykbamXeBKCIr40bB_0M59bG37P1swc6dWvojGic6c5Vqr9HwB-ItUGp8afq2_zBBOMBTV7Ih4FU https://watermark.silverchair.com/151663.pdf?token=AQECAHi20... [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541191/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541191/ [2] https://bmjopen.bmj.com/content/4/4/e004514 https://bmjopen.bmj.com/content/4/4/e004514

option_greek 7y ago

Minor correction: Advantageous to the children (conferring evolutionary advantage). Not to us.

maratd 7y ago
I'm not sure I understand your distinction. From a gene-based perspective, the gene, whether in the child or in the parent, is the same. The selection pressure is on a gene level, not on a species or individual level.

malvosenior 7y ago

The size of the human brain makes this physically impossible.

maratd 7y ago
Ok, explain triplets. https://en.wikipedia.org/wiki/Multiple_birth https://en.wikipedia.org/wiki/Multiple_birth
- malvosenior 7y ago
  Three and twelve are very different from each other. Even three is very rare and often comes with complications.