In the Super Mario World & Yoshi's Island Developer Interview with Nintendo, Takashi Tezuka stated that Mario was originally going to ride a horse instead of Yoshi. However, it felt out of place for a "reptile" world, and was changed to look both like a crocodile and a turtle. A similar concept was almost given to Mario in Super Mario 64, but was later given to Link in Ocarina of Time as Epona.
Contributed by GamerBen144
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