That’s Stefan Aarnio on the impaulsive podcast discussing animals that live in crowded conditions displaying behaviour that isn't observed in the wild. Which is probably where this comment on my video comes from:
Aarnio is referencing British Zoologist Desmond Morris’ 1969 book The Human Zoo. Morris asserts that people in cities will engage in "survival-substitute activities" - such as masturbation and homosexuality - in order to limit the size of the population, like animals in captivity. The implication being that masturbation and homosexuality aren't natural. Or as Aarnio puts it, homosexuality and masturbation are "fucked up things in society."
However, Morris' assertions about the human analogue of sexual deviations among other animals seem to be unfounded based on research findings that human sexual behaviour is not appreciably influenced by crowded conditions (Edwards & Booth, 1977).
Also, as Canadian biologist Bruce Bagemihl points out in his 1999 book Biological Exuberance, the presence of same-sex sexual behaviour was not "officially" observed on a large scale until the 1990s, 20+ years after Morris' book was published. This was due to observer bias caused by social attitudes towards non-heterosexual people, making the homosexual theme taboo.
In fact, among many other examples, homosexual behaviour has been observed in both male (Yamagiwa, 1987) and female (Grueter & Stoinski, 2016) mountain gorillas, wild male Sumatran orangutans (Fox, 2001) and wild white-handed gibbons (Edwards & Todd, 1991).
Given that these homosexual interactions all happened in a completely wild setting, the claim that it is an artefact of captivity is not applicable.
As for masturbation, wild male Phayre's leaf monkeys (Shalauddin et al., 2021) have been observed masturbating. So too have wild bonobo and chimpanzee females (Lee et al., 2020). Wild long-tailed macaques have been observed stimulating a their genitals with stones (Cenni et al., 2020) and a wild male chimpanzee has been observed using a plastic bottle as a masturbatory tool (McLennan and Van Djik, 2021).
Finally, the review of the literature on homosexuality in tribal societies - people living in less dense populations, as per Morris’ theory - indicates striking variations in occurrence, prevalence, and normative reactions to homosexual practices as well as variations according to anatomical sex (Endleman, 1986).
Not to mention the three dozen stories of gay men from rural farms in the midwestern United States - again, people living in less dense populations - as documented by Will Fellows in his 1996 book Farm Boys.
Adaptationism in evolutionary biology, such as Morris' theories, was so prevalent at the time his book was released that it led to one of the most impactful criticisms of evolutionary biology; the "Spandrels paper" written by Gould and Lewontin in 1979.
And prompted British geneticist Adam Rutherford to write in his 2019 book Humanimal, Morris commits "the scientific sin of the 'just-so' story – speculation that sounds appealing but cannot be tested or is devoid of evidence."