General
RAFI: Seeds and Breeds for 21st Century Agriculture
UNDP/RAFI: Hope Shand: Agricultural Biodiversity and Farm-Based Food Security
Sustainable Table: Heritage and Heirloom Foods
Slow Foods USA: Ark of Taste List (Endangered Plants and Animals)
UNFAO: SD Dimensions: Special-Biodiversity for Food and Agriculture
PDF: Heritage Breeds & Heirloom Seeds: The past strengthening our future
Animals
UN FAO: The State of the World's Animal Genetic Resource for Food and Agriculture
UN FAO: Implementing the Global Plan of Action for Animal Genetic Resources
UN FAO: Animal Genetic Resources: First Global Assessment
UN FAO: Spotlight 2006: Farm Animal Diversity
American Livestock Breeds Conservancy: Watch List
Biology Online: Rare Breeds of Farm Animals Face Extinction
Sand Hill Preservation Center: Heirloom Seeds and Poultry
Society for Preservation of Poultry Antiquities
Oklahoma State University: Breeds of Livestock
Organic Agriculture Center of Canada: Heritage Breeds of livestock are in good hands across Canada
Plants
Imperial College: Crop Diversity at Risk: The Case for Sustaining Crop Collections
Gates Foundation: Agricultural Development Fact Sheet
Wikipedia: Heirloom Plants
Guardian: Could new varieties of wheat and barley save the planet from climate change?
Earth and Sky: Save Crop Diversity With Doomsday Vault
Crop Science Journal: The Future of Plant Breeding