Name: Project: Shadow
Nicknames: Shadow, The Ultimate Lifeform, The Black Blur
(He's also, in the past, been saddled a few nicknames which are nothing more than derogatory racial slurs. Needless to say, none of those are official.)
Race: Artificially-processed transgenic Black Arm hedgehog
(Speculation: If you choose to get technical, Shadow is most likely modeled after an African Pygmy Hedgehog, since that is the most common, well-known species of hedgehog, not to mention is the species of hedgehog shown in the US Sonic Adventure 2 and Sonic Adventure 2: Battle commercials.)
Age: N/A; Shadow does not age.
(If you wish to get technical, Shadow's chronological age may very well be about 50 as indicated by the Black Comet's presence by earth "50 years later" as stated by a newspaper in a Last Story cutscene of S