In the Teenage Mutant Ninja Turtles franchise, Donatello is a turtle before mutation.
Donatello is one of four ordinary young turtles transformed into an intelligent, humanoid mutant. He is typically portrayed as the team’s inventor, scientist, and technical expert, balancing the fighting skills of his brothers with engineering and problem-solving.
The exact turtle species is not always presented identically in every adaptation. He is commonly depicted as a snapping turtle or a box turtle, while franchise references and visual designs can differ. The broad, canonical answer to his pre-mutation animal identity is therefore turtle.
Donatello is usually recognized by his purple mask and bo staff. His name honors the Renaissance sculptor Donatello, continuing the naming pattern shared by all four turtles.