55-million-year-old fossil bird shows how trogons evolved their unusual feet
A fossil of Daniatrogon kochi, discovered in Denmark, provides insights into the evolution of trogon feet. Researchers found that the trogons' unique foot morphology developed gradually over time. The fossil also shows changes in the shape of their beaks, which were narrower than those of modern species. Additionally, early trogoniforms displayed more varied beak and foot shapes, indicating a diverse ecology.

