List of PLANET EARTH groups contest now going on.

PLANET EARTH OUR HOME

http://www.flickr.com/groups/744944@N20/

PLANET EARTH TRANSPORTATION

http://www.flickr.com/groups/1296231@N25/

PLANET EARTH ANIMALS/BIRDS

http://www.flickr.com/groups/939028@N23/

PLANET EARTH FLOWERS

http://www.flickr.com/groups/1328471@N22/

PLANET EARTH ARCHITECTURE

http://www.flickr.com/groups/966432@N21/

PLANET EARTH IN BLACK AND WHITE

http://www.flickr.com/groups/1060854@N24/