Historical clue formulations

• Capybara, for one — 2021-09-25
• Gopher, e.g. — 2020-04-05
• Woodchuck or chinchilla — 2015-03-12
• Squirrel, e.g. — 2014-05-04
• Porcupine, e.g. — 2011-04-06
• Porcupine or gopher — 2010-06-22
• Chinchilla, e.g. — 2009-02-22
• Maze participant — 2005-03-13
• Rat or squirrel — 2004-08-09
• Lab test taker — 2002-11-29
• Natural nibbler — 2002-01-06
• Chinchilla or beaver, e.g. — 2001-11-19
• Porcupine, for one — 2001-10-25
• Mouse or beaver, e.g. — 1998-02-16
• Bandicoot, e.g. — 1997-11-29
• Guinea pig or groundhog — 1994-09-05