Dr. Marc van Roosmalen (born 23 June 1947, Tilburg) is a Brazilian primatologist of Dutch birth living in Manaus in Brazil. He was elected as one of the "Heroes of the Planet" by Time Magazine in 2000. His research has led to the identification of several new monkey species, as well as other animals and plants, although some of these identifications are challenged as dubious, unconvincing, or contradictory to the evidence. He is also an activist in the protection of the Brazilian rainforest.