Kevin Schafer / Rosy Periwinkle (Catharanthus roseus) leaves and flowers used for anti-cancer medicine, Madagascar

Ingo Arndt / Rosy Periwinkle (Catharanthus roseus) pair in bloom, plants are harvested for medicinal use, Madagascar

Ingo Arndt / Rosy Periwinkle (Catharanthus roseus) in bloom, plants are harvested for medicinal use, Madagascar

Pete Oxford / Rosy Periwinkle (Catharanthus roseus) a medicinal plant in bloom, Isalo Massif, Isalo National Park, Madagascar

Gerry Ellis / Rosy Periwinkle (Catharanthus roseus) in bloom, plants are harvested for medicinal use, Madagascar