Small animals (so called 'minimals' in the file system of Sonic Adventure 2,1 doubtles a portmanteau of 'mini' and 'animal') are small, relatively non-anthropomorphic animals that have appeared in the Sonic series ever since the very first game.2
Given the name, 'small animals' probably isn't a catch-all term for non-anthropomorphic animals in Sonic's world, since many of these are, in fact, large.3 I wonder if the big chunguses in Superstars count...
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