Her big book was Darwin and the Darwinian Revolution (1959) available online as well.
Flannery sets the cultural scene pretty well, in his #10 of the Top Ten stories at ENST:
It is comforting to know that Himmelfarb never lost her intellectual acuity or her moral passion on the subject. When asked to review E.O. Wilson’s edits of Darwin’s four great works in From So Simple a Beginning and James D. Watson’s Darwin: The Indelible Stampfor The New Republic (December 12, 2005) she wrote an insightful essay, “Monkeys and Morals,” and was reminded of being introduced to Julian Huxley (grandson of Darwin’s bulldog, Thomas Henry Huxley, then Darwin’s faithful puppy) in 1958 at a cocktail party on the eve of her book’s publication. When Gertrude suggested to Julian that her book might shed new light on Darwinian evolution, he immediately protested, “New! There is nothing new to say about evolution. Everything that needs saying has already been said. The theory is incontrovertible.” She says that abruptly ended the conversation. Huxley marched off for better company. How little things have changed! And indeed Dr. Himmelfarb must have had déjà vu as she reviewed Wilson and Watson’s books. She wrote:
“The editors of these new editions of Darwin may have taught us more than they know. A non-scientist may well stand in awe of the enormous achievements that they as individuals, and scientists in general, have to their credit. They have learned a great deal, and we have learned a great deal from them. But what they have evidently not learned is humility — an appreciation of the limits of science, of what science does not know and cannot know.”
She concluded her review warning of our rapid descent into scientism, “for it is not only science that is now presumed to be the only access to truth, but also the subcategory of science known as Darwinism.”
Michael Flannery, “#10 Story of 2020: Farewell to Gertrude Himmelfarb” at Evolution News and Science Today:
It’s not even clear any more whether Darwinism is a subcategory of science, as such. It seems to be more of a cultural argument today.
It doesn’t solve any problems in science but it enables pop psychology to come up with any number of creative explanations for human behavior. = “The evolutionary psychologist knows why you vote — and shop, and tip at restaurants” That’s enough for a certain sort of intellectual culture.