Plant pathologists sequenced the genome of 19th century potato specimens like this one from London's Kew Gardens herbarium, collected during the height of the Irish famine in 1847. Marco Thines/Senckenberg Gesellschaft für Naturforschung hide caption

itoggle caption Marco Thines/Senckenberg Gesellschaft für Naturforschung

Potatoes come in all colors, like these Red Erik, Snowball, Cariboo, Purple Peruvian, Caribe and French Red varieties. David Cavagnaro/Corbis hide caption

itoggle caption David Cavagnaro/Corbis