Historical clue formulations

• Habitat for [circled letters] — 2026-06-21
• Habitat for giraffes — 2023-03-11
• Tropical grassland — 2015-06-15
• Zebra zone — 2010-10-23
• Tropical grassland — 2009-10-25
• Grassland dotted with trees — 2006-05-20
• Treeless plain — 2004-12-19
• Where zebras and giraffes graze — 1997-09-07