9- At the crossroads of science and art, this catalogue compares the main milestones of scientific discoveries with their parallels in the collective imagination- Featuring 300 works which testify on the influence of scientific discoveries on the imagination and art of the 19th century- Accompanies an exhibition at Musée d'Orsay in Paris: December 2020 - May 2021. The exhibition has been organized with the Montréal Museum of Fine Arts, Canada, which will take place from June - 27 September 2021The 19th century saw an unprecedented development of the natural sciences. Darwinian theory questions the origins of man, his place in Nature, his links with animals and his own animality in a world now understood as an ecosystem. This upheaval in the sciences, as well as the public debates throughout the century, deeply influenced the artists. The Musée d'Orsay and the Musée des Beaux-Arts de Montréal are devoting an exhibition to the intersection of science and the arts for the first time, in partnership with the National Museum of Natural History in Paris, which will retrace the themes of this questioning and will confront the main milestones of scientific discoveries with their parallel in the art.