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Why do tuatara use uric acid as waste?
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tuatara
The species is the sole living member of the reptile order Rhynchocephalia.
Tuatara, like many other terrestrial reptiles, excrete uric acid as a primary nitrogenous waste product to conserve body water.12
Unlike ammonia or urea, which are highly soluble in water and require significant amounts of fluid to be excreted, uric acid is insoluble and relatively harmless. By converting nitrogenous wastes into an insoluble, solid, or semisolid mass, tuatara can eliminate these substances with minimal water loss. This physiological adaptation is essential for maintaining water balance in their terrestrial environment. These wastes are passed into the cloaca, where they are mixed with fecal material before being expelled from the body.1324