rosy periwinkle

Although the rosy periwinkle stands only one foot tall, in the world of medicine it's a giant. In the 1950s, scientists figured out how to use chemicals from this plant to treat childhood leukemia and Hodgkin's disease. Before then, most people who got these diseases died. The rosy periwinkle is one of thousands of plants that produce chemicals that can help save human lives.

Scientific name: Catharanthus roseus
Size: one foot tall
Habitat: forests of Madagascar
Characteristics: shiny green leaves, a small pinkish flower
Significance: contains chemicals called vincristine and vinblastine, which help people with Hodgkin's disease and childhood leukemia (both are forms of cancer)

Image credits: main image: courtesy of James Manhart.