Desor studied law at Giessen and Heidelberg, was compromised in the republican movements of 1832/3 (see, for example, Hambach Festival and Frankfurter Wachensturm), and escaped to Paris.

He made excursions with Élie de Beaumont, and in 1837 met Louis Agassiz at a meeting of naturalists in Neufchâtel.

With Gressli and Vogt, Desor became an active collaborator with Agassiz, studying palaeontology and glacial phenomena, and contributing the essays for vol.

He spent a few years in the north of Europe, especially in Scandinavia, investigating the erratic phenomena peculiar to that region, From strata he examined in Denmark he introduced the term Danian in 1847, to characterize the oldest stage of the Paleogene.

He also investigated the old lake-habitations of Switzerland, and made important observations on the physical features of the Sahara.