Robert Trivers is an American sociobiologist and anti-transgender activist. Trivers was a key figure within Jeffrey Epstein’s circle regarding Epstein’s interest in funding “research” about transgender people.
Background
Robert Ludlow “Bob” Trivers was born on February 19, 1943 in Washington, DC. Trivers earned a bachelor’s degree from Harvard University in 1965 followed by a doctorate there in 1972. Trivers taught at Harvard as an assistant professor before moving to the University of California, Santa Cruz.
Between 1971 and 1974, Trivers published a series of influential papers on evolutionary biology. In 1971, Trivers introduced the theory of reciprocal altruism, explaining how cooperation could evolve among unrelated individuals over time. In 1972, Trivers proposed the theory of parental investment, outlining how differences in reproductive costs influence mating behavior. Trivers’ 1973 paper on parent–offspring conflict further expanded understanding of family dynamics in evolutionary terms. Trivers’ 1974 work on self-deception suggested that the ability to deceive oneself may enhance the capacity to deceive others. In 1976, Trivers’ major papers were collected in the volume Social Evolution.
Trivers and mathematician Austin Burt co-authored Genes in Conflict in 2006. Trivers later joined Rutgers University as a professor of anthropology and biological sciences. Trivers was dismissed from Rutgers after refusing to teach an assigned course.
Trivers’ 2015 memoir Wild Life: Adventures of an Evolutionary Biologist describes episodes that Trivers later characterized as manic or psychotic, leading to periods of hospitalization.
Anti-trans activism
Trivers was a close associate of sex trafficker Jeffrey Epstein. The 2026 release of the Epstein Files revealed how close they were.
On October 5, 2009, Epstein invited Trivers to Florida.
On October 20, 2015, Epstein told Noam Chomsky about funding Trivers: “i am his major funder. he got thrown out of ru=gers for good this time.”
On February 6, 2016, Trivers thanked Epstein for an advisory position with Epstein’s foundation and for funding recently received. Trivers says it “will go entirely toward the theoretical work you have urged upon me.” Epstein responded, “i want to see you piece on transgender in the bio world.”
On March 29, 2016 request for additional funding, Trivers told Epstein:
i am getting to the end of ‘transsexuality’—need again only to choose venue and adjust style—have had a lot of fun with the attraction of the new morph(s)—have your cake and eat it too—a woman with a dick—i.e. if you as a heterosexual male and have a minor desire to suck a dick then what better organism to do it with than a transsexual? ‘she’ will smell like a woman, be softer and more hairless like a woman and may, to some degree, actually resemble one morphologically—leaving the dick for you to enjoy in a feminine setting.”
On October 20, 2016, Trivers spoke in Croatia at Simpozij O snazi evolucijske misli [Symposium On the Power of Evolutionary Thought]. One of Trivers’ talks was titled “An Evening on Evolutionary Biology: An overview concerning Feminism, Transgender, Homosexuality, and Honor Killings.” In a video that has since been taken private, the organizers wrote: “It was a great honor for us to invite you to the 2nd Symposium on the Power of Evolutionary Thought, which this year hosted Prof. Robert Trivers, one of the greatest and most influential biologists and evolutionary theorists of our time, on the first stop of his European tour. The man whom Steven Pinker considers one of the most significant thinkers in the history of Western thought, and whom Times included among the 100 greatest thinkers and scientists of the 20th century, presented some of his most influential ideas, his new projects, and also shared his extraordinary life experiences in four extremely interesting lectures in Zagreb from October 10th to 13th.”
In the lecture, Trivers rambles through a disorganized mishmash of beliefs about trans people and estimates prevalence at between 1 in 1,000 to 1 in 30,000. The actual prevalence is estimated to be about 1 in 100.
Trivers and Epstein stopped corresponding for a time while Trivers was employed at Chapman University. Based on references in a March 31, 2018 email to Chapman President Daniele Struppa and copied to Epstein, Gordon Getty, and Howard Crabtree, Trivers was apparently accused of indecent exposure by Struppa’s assistant.
On December 17, 2018, Trivers sent the following update to Epstein:
it is very simple—i will compare male to female with female to male
with greater molecular control over development we are increasingly capable of producing novel phenotypes—more feminine men, by blocking testosterone receptors (or castration) and, at the same time, increasing estrogen production—the one bocks male features, the second encourages female features more masculine women—heavy testosterone dosage—incredible external effects, heavily bearded men, you would never guess they had a female bone in their body
first kind—male -> female is 4 times more frequent than female -> male
the first is attractive—he is a woman with a cock, so that if your fantasy is to suck a man’s dick, otherwise you are completely heterosexual, it would be much nicer if the rest of the organism is female, then you get the best of both worlds so many transsexual women are very attractive and easily make money which in turn they assert promotes their prostitution since they have to pay hefty fees for injections every week, but they are sexually happy,–once you have reached manhood even castration does not prevent the sensation of organism contrast the poor female to male versions, they are unhappy and lonely—they are men with mum-pums, the worst of both worlds
if you like smelly masculine men, you want that hard cock that comes with the show—you do not want one of nature’s more complex and variable structures, the pum-purn—that is an acquired tasted—and not with a man there are 100’s of female Trans videos and websites, i have never seen a male one
BTW we are now pushing the intervention earlier–so you notice your 3-year old son has trans tendencies, so now you intervene with hormones—i would be frightened to do that—but who knows ?
In an excellent overview on Trivers, Ev Nichols noted, “He is clearly a chaser who wants to use his status as a researcher to naturalize his own sexual appetites.”
On March 16, 2019, Trivers complained to Epstein about Epstein’s recent lack of financial support: “after 7 years of continuous support, you seemed to flip, no support at all for past two years nor response to requests.” On March 16, 2019, Epstein responded to Trivers in part:
“I thought that you might want to focus on transgender biology . people would be interestsesd and i would fund. I am a true beileiver in your talents. my understanding and of course it could be incorrect. was that honor killing work was detrimental for you. as was the knee hip ratio in sprinters etc.. little public interest where the genetics of exceptional and transgender would be helpful.”
In June 2020, Trivers published a paper in the journal Evolutionary Psychological Science with John T. Manning and Bernhard Fink hypothesizing that “Transgendered belief—the conviction that one is the opposite gender to one’s natal gender—may be influenced by prenatal sex steroids.”
References
Nichols, Ev (February 3, 2026). How the pseudoscience is made: From dark money to an academic journal. Queer Science Lab https://queersciencelab.beehiiv.com/p/how-the-pseudoscience-is-made-from-dark-money-to-an-academic-journal
Serano, Julia (February 12, 2024). Why Are “Gender Critical” Activists So Fond of Gametes? Switch Hitter https://juliaserano.substack.com/p/why-are-gender-critical-activists
Selected writing by Trivers
Manning, J.T., Trivers, R. & Fink, B (2020). Digit Ratio (2D:4D), Transgendered Belief, and Transsexual Drug Therapy in the BBC Internet Study. Evolutionary Psychological Science 6, 380–388. https://doi.org/10.1007/s40806-020-00247-9
Manning, J. T., Fink, B., & Trivers, R. (2017). Biology of Human Gender, The. In Encyclopedia of Evolutionary Psychological Science (pp. 1–5). Springer International Publishing. https://doi.org/10.1007/978-3-319-16999-6_3827-1
Media
Simpozij O snazi evolucijske misli (October 20, 2016). An Evening on Evolutionary Biology: An overview concerning Feminism, Transgender, Homosexuality, and Honor Killings. https://www.youtube.com/watch?v=_ij__9Ff-u8 [taken private – archive – trans section starts at 28:00]
Resources
Robert Trivers (roberttrivers.com)
Wikipedia (en.wikipedia.org)
Google Scholar (scholar.google.com)
- Robert Trivers
- scholar.google.com/citations?user=lLppkZQAAAAJ