There is something in male biology and juices that masks or overtakes normal defensive behavior when faced by a female enemy

Nobel Prize Winner Daniel Kahneman writes the following on loss aversion (in his epic book "Thinking fast and Slow"

"..... Animals including people, fight harder to prevent losses than to achieve gain. In the world of territorial animals, this principle explains the success of defenders. A biologist observed that "when a territory holder is challenged by a rival, the owner almost always wins the contest - usually within a matter of seconds.... " 

My question : How did men, who were supposed to be born defenders give up so much of their "matrimonial" and democratic territory when faced by radical feminists and their ilk ?

My conclusion : There is something in male biology and juices that masks or overtakes normal defensive behavior when faced by a female enemy. Probably that is why the great Acharyas in history, refused to fight women and shikandis (transgenders)

I'd be grateful to all those who can share their thoughts as comments below