Go ahead and name 20. While I wait, here's an article by a left leaning media outlet that quotes multiple PhDs saying gender is not just a social construct. Furthermore they go on to shed light on the political pressure they feel when they study these phenomena and that its mostly left leaning groups that attack the objective science. Not a good look for liberals if we can't accept science.
"In other words, contrary to the popular progressive belief, gender is partly socially constructed—but it’s not
just a social construct."
“Many people are uncomfortable with the idea that gender is not purely a social construct,” says Todd, who notes that her work has faced “very critical attention.” There’s a political preference—especially on the left—Todd believes, for gender to be only a reflection of social factors and so entirely malleable."
"Eagly argues that policy should not influence science. “Science strives for valid findings, the truth of the findings, regardless of whether you like them or I like them. We strive to find out how the biology of people works. Would we close our minds as scientists because it might be politically incorrect?,” she says. How the evidence could influence policy is not up to her, she adds. “I’m not a social policy expert,” says Eagly."
“I don’t know any real researcher of human behavior who would say it’s all nature or all nurture.”
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There's 2 more PhDs, so take your time, 60 might take awhile..