[3] He also undertook several hybridization experiments at the zoo, including a blackbuck × Dorcas gazelle cross, as well as among varieties of leopards or jackals.
[3] In 1930, de Beaux published "Biological ethics: an attempt to arouse a naturalistic conscience", which Pedrotti called "his most important study.
In one paper on the European bison, he argued that "man is not in the world to destroy or exploit nature, but to preserve it and increase its value".
Pedrotti stated that de Beaux's biological ethic could be summed up as "take care that no animal or plant species disappears from the face of the earth, that is, respect every expression of life, which encloses within itself its own solution to the immense problem of existence".
[1] De Beaux also emphasized the role of education in conservation, highlighting the importance of facilities such as zoos, aquaria, natural history museums, and botanical gardens.