Cuvier taught him — noted ichthyologists both. He acted as artist and naturalist on Baudin’s voyage to Australia, having signed up as a gunner: Péron was his colleague, and became a friend for life. Lesueur Met Maclure in Paris, and travelled extensively with him on scientific expeditions, joining his and Owen’s celebrated ‘Boatload of Knowledge’ from Pittsburgh to the utopian community of New Harmony (“more learning than ever was contained in a boat” was Owen’s description). Say, part of the same community, became a lifelong friend. Bodmer struck up a friendship with Lesueur and Say on a visit to New Harmony.