「Like humans but unlike chimps and most other animals, bonobos separate sex from reproduction. They seem to treat sex as a pleasurable activity, and they rely on it as a sort of social glue, to make or break all sorts of relationships. 'Ancestral humans behaved like this,' proposes Frans de Waal, an ethologist at the Yerkes Regional Primate Research Center at Emory University. 'Later, when we developed the family system, the use of sex for this sort of purpose became more limited, mainly occurring within families [i.e., incest]. A lot of the things we see, like pedophilia and homosexuality, may be leftovers that some now consider unacceptable in our particular society.' 」
[ https://www.discovermagazine.com/mind/casual-sex-play-common-among-bonobos 2023-05-14 ]
「The bonobo, an African ape closely related to humans, has an even bigger sexual appetite. Studies suggest 75 percent of bonobo sex is nonreproductive and that nearly all bonobos are bisexual.」 [ https://www.mentalfloss.com/posts/weird-animal-sex-facts 2023-05-44 ]
「Historical accounts from the 18th century indicate that adult-child sex (particularly same-sex pairings) were an accepted practice in China, Japan, Africa, Turkey, Arabia, Egypt, and the Islamic areas of India (Trumbach, 1977). In 19th century London the going price for a virginal, 12-year-old girl, of good background, was reported to be 400 pounds (Bullough, 1964).」
[ https://www.ipce.info/library/journal-article/legal-social-and-biological-definitions-pedophilia 2012-01-01 ]
「In traditional Chinese medicine, there has never been a mental disease called pedophilia (or an equivalent term), or homosexuality, or most of the other so-called sexual variations [such as incest] for that matter. …Children are usually described as natural sexual beings and erotic stimulation and sex-play are seen as beneficial to their healthy development.」
[ https://docx2.com/wp-content/uploads/Are-Any-of-the-Pharaphilias-in-DSM-Mental-Disorders_.pdf 2023-05-14 ]
「In Japan, it is not uncommon for mothers to sexually stimulate their children to soothe them so they will sleep. There have been stories in the press of mother-son incest arising from the strong nature of this relationship in Japan and the important maternal role of ensuring the son succeeds at school. According to Hideo Tokuoka, 'When Americans think of incest, they think of fathers and daughters. In Japan one thinks of mothers and sons' due to the extensive media coverage of mother-son incest there.」
[ https://en.wikipedia.org/wiki/Incest 2012-08-21 ]
Many, if not most, anthropologists understand that bonobos today exhibit the behavior of early humans, and modern humans, too:
「Sometimes females would rather GG-rub [genital-to-genital] with each other than copulate with a male. Parish filmed a 15-minute scene at a bonobo colony at the San Diego Wild Animal Park in which a male, Vernon, repeatedly solicited two females, Lisa and Loretta. Again and again he arched his back and displayed his erect penis—the bonobo request for sex. The females moved away from him, tactfully turning him down until they crept behind a tree and GG-rubbed with each other.」
[ https://www.discovermagazine.com/mind/casual-sex-play-common-among-bonobos 2023-05-14 ]
「Recent surveys of teenage girls and young women find that roughly 15% of young females today self-identify as lesbian or bisexual, compared with about 5% of young males who identify as gay or bisexual. …Female sexuality is different from male sexuality. If a straight boy kissed another boy, perhaps to amuse some girls who might be watching, he would be unlikely to undergo a change in sexual orientation as a result. But, as Professor Roy Baumeister at Florida State University and others have shown, sexual attraction in many women seems to be more malleable…. If a teenage girl kisses another teenage girl, for whatever reason, and she finds that she likes it—then things can happen, and things can change. If a young woman finds her soulmate, and her soulmate happens to be female, then she may begin to experience feelings she's never felt before.」
「Especially if all the guys she knows are losers.」
[ https://www.psychologytoday.com/intl/blog/sax-sex/201004/why-are-so-many-girls-lesbian-or-bisexual 2023-05-17 ]