Marx Brothers made a guest appearance to introduce the "Tonight Show's" new host, Johnny Carson. Around 1960, the acclaimed director Billy Wilder considered writing and directing a new Marx Brothers film. Tentatively titled "A Day at the U.N.", it was to be a comedy of international intrigue set around the United Nations building in New York. Wilder had discussions with Groucho and Gummo, but the project was put on hold because of Harpo's ill-health and abandoned when Chico died in 1961. He was 74. Three years later, on September 28, 1964, Harpo died at the age of 75 of a heart attack
Influences on Karl Marx "when Darwin drew the conclusions from his research work and brought them to the knowledge of the public, we spoke of nothing else for months but Darwin and the enormous significance of his scientific discoveries". Historian Richard Weikart points out that Marx had started to attend "a series of lectures by Thomas Henry Huxley on evolution". In August 1866, Marx referred to Pierre Trémaux's "Origine et transformations de l'homme et des autres êtres" (1865) in another letter to Engels as "a very important advance over Darwin". He went further to claim that "in its historical and political application" the book