Historical clue formulations

• Black-and-white divers — 2024-12-21
• Puffins, e.g. — 2023-05-14
• Great ones are extinct — 2022-12-03
• Relatives of puffins — 2019-01-02
• Arctic fliers — 2017-01-08
• Dovekies, e.g. — 2016-10-29
• "Great" birds — 2014-05-18
• Arctic seabirds — 2012-08-01
• Razor-billed birds — 2011-10-25
• Diving seabirds — 2011-06-05
• "Great" birds — 2005-05-22
• Razor-billed birds — 2004-02-15
• Diving birds — 2003-04-13
• Web-footed birds — 1995-11-22