• 13 Natural history
• 10 Animals
• 8 Ecology
• 5 Earth sciences
• 4 Climatic changes
• 2 Biotic communities
• 2 Desert ecology
• 2 Forests and forestry
• 2 Global warming
• 2 Habitat (Ecology)
• 2 Marine animals
• 2 Marine ecology
• 2 Ocean
• 1 Aquatic ecology
• 1 Atmosphere
• 1 Caves
• 1 Coral reefs and islands
• 1 Deserts
• 1 Forest ecology
• 1 Fresh water
• 1 Geology
• 1 Glaciers
• 1 Grasslands
• 1 Hydrologic cycle

• 12 Attenborough, David, 1926-
• 12 Discovery Channel (Firm)
• 12 Fothergill, Alastair
• 12 Nihon Hōsō Kyōkai
• 11 BBC Worldwide Americas, Inc.
• 5 BBC Worldwide Ltd.
• 5 Lawrie, Ben
• 5 National Geographic Channel (Television station : Washington, D.C.)
• 5 Renouf, Jonathan
• 5 Stewart, Iain S.
• 4 Cordey, Huw
• 3 Berlowitz, Vanessa
• 3 Brownlow, Mark
• 3 Linfield, Mark
• 2 Byatt, Andrew
• 2 Keeling, Jonny
• 1 Allen, Penny
• 1 Allen, Penny, Dr
• 1 BBC Worldwide Americas, Inc
• 1 Canadian Broadcasting Corporation
• 1 Gillings, Annabel
• 1 Gyves, Matthew
• 1 Harris, Sophie Elwin
• 1 Olding, Paul, 1973-

• 17 English

• 1 Cold regions
• 1 Eastern Hemisphere
• 1 Everest, Mount (China and Nepal)
• 1 Himalaya Mountains
• 1 Northern Hemisphere
• 1 Polar regions
• 1 Solar system
• 1 Southern Hemisphere
• 1 Tropics
• 1 Western Hemisphere

• 17 Documentary television programs
• 15 Science television programs
• 11 Nature television programs
• 1 Documentary
• 1 Television mini-series
• 1 Television programs
• 1 Television special
• 1 Video recordings for the hearing impaired

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