Editing Homininae (section)

===Evolution of family structure and sexuality===
{{Update|section|reason=Cited evidence is out of date.|date=June 2023}}
{{see also|Human sexuality}}
Sexuality is related to family structure and partly shapes it. The involvement of fathers in education is quite unique to humans, at least when compared to other Homininae. [[Concealed ovulation]] and [[menopause]] in women both also occur in a few other primates however, but are uncommon in other species. [[Testis]] and [[penis size]] seems to be related to family structure: [[monogamy]] or [[promiscuity]], or [[Harem (zoology)|harem]], in humans, chimpanzees or gorillas, respectively.<ref>{{cite book|last=Diamond|first=Jared | name-list-style = vanc |author-link=Jared M. Diamond|title=The Third Chimpanzee|year=1991|title-link=The Third Chimpanzee}}</ref><ref name="WiSF">{{cite book|last=Diamond|first=Jared| name-list-style = vanc |title=Why is Sex Fun?|year=1997|title-link=Why is Sex Fun?}}</ref> The levels of [[sexual dimorphism]] are generally seen as a marker of [[sexual selection]]. Studies have suggested that the earliest hominins were dimorphic and that this lessened over the course of the evolution of the genus ''Homo'', correlating with humans becoming more monogamous, whereas gorillas, who live in harems, show a large degree of sexual dimorphism. Concealed (or "hidden") ovulation means that the phase of fertility is not detectable in women, whereas chimpanzees advertise ovulation via an obvious swelling of the genitals. Women can be partly aware of their ovulation along the menstrual phases, but men are essentially unable to detect ovulation in women. Most primates have semi-concealed ovulation, thus one can think that the common ancestor had semi-concealed ovulation, that was inherited by gorillas, and that later evolved in concealed ovulation in humans and advertised ovulation in chimpanzees. Menopause also occurs in [[rhesus monkeys]], and possibly in chimpanzees, but does not in gorillas and is quite uncommon in other primates (and other mammal groups).<ref name="WiSF"/>