“When pop culture decided any male role model was as good as, and sometimes better than, the real father, the kids were headed for predictable damage for generations.”
At this point the optimal “father” for a boy is NOT the real father (usually portrayed as a POS), but the compassionate understanding metrosexual who wants a relationship with the boy’s mother (and loves her child so much he never seems to want his own). Nature (and the news) clearly indicate this is BS; when a new alpha male takes over a baboon troop, he spends a few days killing any children of his predecessor (despite the efforts of the mothers to prevent it). When they are dead he can mate with the mothers.
This happens EVERY DAY in the nearby Newark NJ welfare reservation; while some stepfathers are wonderful people, and some are better “fathers” than the real fathers, statistically it is a disaster for the children. In my experience (as a son and a father) nobody will ever love a child as much as the biological parents (I know some disagree with this, but this is my experience).
As for taking cues from nature there are plenty of examples of dysfunctional mothers of various species eating their own young. I don't think that we need to take lessons from them, but as is apparent from humans and the abortion rate, there are plenty of people that love children more than their biological parents.