The African lungfish, Protopterus dolloi, has a unique ability to maintain low blood plasma ammonia levels despite exposure to high environmental ammonia concentrations. This is achieved through a combination of ammonia excretion and detoxification mechanisms. The lungfish's ability to synthesize urea from ammonia is a key factor in its detoxification process. This study highlights the importance of urea synthesis in the African lungfish's ability to cope with environmental ammonia toxicity.