Overall, my results confirm the theoretical plausibility of what has been viewed as a critical step in the evolution of our own species—the transition from promiscuity to strong pair-bonding. The model shows that such a sexual revolution could have been initiated by low-ranked males who started provisioning females to get matings; after the process got underway, it would lead to a kind of self-domestication, and the end result is a group-living species comprised of provisioning males and largely faithful females.
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The transition to strong pair-bonding opened a path to intensified male parental investment, which was a breakthrough adaptation with multiple anatomical, behavioral, and physiological consequences for early hominids and all of their descendants.
The establishment of pair-bonding shifted competition between males for mates, which was potentially destructive for the group, to a new dimension which is beneficial for the group —competition to be a better provider to get better mates. Pair-bonding provided a foundation for the later emergence of the institution of modern family as an outcome of additional processes, such as wealth accumulation and inheritance. Pair-bonding also made possible the recognition of male kin, dramatically expanding the efficiency of kin selection and helping by grandparents, leading to stronger within-group coalitions and alliances, and allowing for subsequent evolution of widespread cooperation in general