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Conservation Status Categories

Countries by Population Density

Global Recycling Symbols

Historical Climate Change Events

Key Geological Periods

Island Nations

Major Tectonic Plates

Ocean Currents and their Effects

Oceanography: Ocean Layers

Plate Tectonics: Types of Boundaries

Types of Biomes

World's Largest Lakes

World's Longest Mountain Ranges

Water Cycle Stages

Renewable and Non-renewable Resources

Significant Deserts of the World

Significant Coral Reefs