4 ms·
> The survival of a baby mostly trumps the needs of a mother for passing on genes (a gene where a child lives to breed has a very strong selection pressure), so
by svnt 4y ago
> The survival of a baby mostly trumps the needs of a mother for passing on genes (a gene where a child lives to breed has a very strong selection pressure), so that probably is one major reason.
This is generally not true for species that take a long time to reach reproductive maturity, and more so if they evolve to become physically underdeveloped at birth. A (proven) fertile human female is reproductively much more valuable than a newborn.
- robocat 4y agoYeah, on second thoughts you are right because I hadn’t thought about what happens to the mothers that lack the gene. If there are genes that kill mothers, the child has the chance to pass on the gene, which is a strong selection pressure for the child. However meanwhile mothers without that gene will have more babies, so the selection pressure is mostly whether the mother has the gene or not, because mothers without the gene will have more descendants. It’s difficult to think through realistic examples, and probabilities.
- svnt 4y agoYeah there is a lot of complexity to the process. Other things to consider include that if the child’s genes kill the mother they generally do this by causing the child to fail to exit the mother, which also kills the child. The exception to this would mostly be genes that result in the mother’s death from blood loss, after the child had exited, so related to placental issues/placement. But for this to succeed for the child it also assumes someone else would care for the child as well as the mother would have, which is unlikely at best.