Let's see... I do think Hitler died in '45, though I'm familiar with theories to the contrary. Hirohito, Mao, and Stalin were certainly responsible for a great deal of death and suffering; as were Harry Truman and (to a lesser extent perhaos) FDR. The evolutionary theories of Darwin are nearly irrefutable in their broad strokes, though scientists have corrected and filled in a lot of details in the intervening years. Margaret Sanger was for the most part an activist for women's rights whose interest in eugenics has been exaggerated by the anti-abortion crowd - MLK, as just one example, cited her as one of the major inspirations for his work in the civil rights movement. There is no Margaret Sanger extermination plan. None of this has much of anything to do with global warming, which I intuit is what you're addressing in your last two sentences.