Evolution moulds phenotypes, where trade-offs exist at the structural and functional level. They can be considered playing an important role for those systems that are involved in different functions with potential conflicting demands for increased performance. This project focuses on the the buccal system in mouthbrooding cichild fishes, performing in feeding, respiration, agonistic display, nest building and mouthbrooding. We analyse structural, functional and physiological trade-offs in the buccel system of hapmochromine species of lake Victoria.