@iraantlers the first few chapters she does a great job of explaining how it was considered a given that fathers/men were not biologically capable of caring for their offspring and so much was built on that foundation that turns out to be false. Science is not immune to believing things that turn out to be untrue and harmful (which is of course not news at all). This is also a poor summary of the first few chapters, I highly recommend reading it!
What’s fascinating about it is that, given the opportunity to be in close and prolonged contact with newborns, humans in general, including men, undergo the same hormonal changes that we normally associate with just mothers!