“Naoto Ohshima is a Japanese artist and former Sega employee who is best known for his original character designs of Sonic The Hedgehog and Dr.Eggman.”
https://en.wikipedia.org/wiki/Naoto_Ohshima
Naoto Ohshima was born in Japan February 26th, 1964 and is currently age 53. When Sega was creating a new platformer at the time, programmer (Yuji Naka) had already created the original tech demo in which Sonic was based, they still had a problem in that there was no exact character that they had which would be the mascot for the game and so at the time the mascot was just a ball with no specific features. The Sonic Team considered numerous animals that they could use as the game’s mascot. They wanted to use an animal that was known for rolling into enemies with its spikes and naturally, the top choices were between an armadillo and a hedgehog.
Naoto Ohshima clearly liked the hedgehog idea a lot more and the picture below shows the original ideas for Sonic ( From the time he was known as Mr.NeedleMouse) all the way up until the final design.
Sonic’s earliest stage (At the time known as Mr.Needlemouse)
Sonic at his rough concept art stage
Sonic’s final rendering
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