Einstein Science Reporting for Kids
[ E-mail Share Share ]
11-Jan-2007

Contact: Science Press Package
scipak@aaas.org
202-326-6440
American Association for the Advancement of Science

Family found for giant, stinking flower



First discovered nearly 200 years ago in the Sumatran rain forest, an unusual flowering plant with the largest single flower - typically a full meter across and weighs up to 15 pounds - has finally found its home in the botanical tree of life.

About the plant

The large flowering plant is named rafflesiaceae after one of the men who discovered it. It is the queen of parasitic plants and lives off of a plant in the grapevine family. The plant's flower is blood red and stinks of rotting flesh, which, according to one of the researchers, Charles C. Davis, attracts the carrion flies that pollinate them. Some of the plants can even generate heat to attract flies, he said. The plant lives in the understory rain forest in Southeast Asia.



Botanist Charles C. Davis collects plants in Cameroon, West Africa to study later in his laboratory.

Finding a family

Botanists place plants in families that share similar traits - much like a human family does. But this plant was a challenge because it is a parasite so it does not have vegetative structures such as leaves and stems. And because it is a parasite, it has adopted some of the grapevine's genetic material making it even harder to determine which family to place it in. The fact that the flower of the plant is so unusual adds another challenge to finding its family.

Researchers have worked for decades to find a place for this unusual plant. Using the latest DNA techniques, researchers used a variety of type of DNA molecule markers, and matched the plant to family named Euphorbiaceae. These plants' flowers are hundreds of times smaller than rafflesiaceae!

"We were surprised that rafflesiaceae belongs to this family because we thought we knew and understood a lot about them," said Davis. This family of plants has much smaller flowers and includes Irish bells and poinsettias. The family also has some important crops - including the rubber tree, castor oil plant and the cassava shrub, which is used throughout much of the world as an important part of their diet like many people eat a lot of rice or beans.

There is still more to know about rafflesiaceae. Researchers want to know how it became such a giant. "When we look at its most recent ancestor, this flower is 79 times larger," said Davis. "That would be like an adult human (about 2 meters) compared to the Great Pyramid of Giza, which is 146 meters tall! It is so weird, it makes your head spin and it is hard to know where to begin studying.

About the researcher

Davis works at Harvard University's Herbarium which is a museum of plant specimens. "I spend half the year in out-of-the-way places in tropical countries collecting plants like Indiana Jones and then I come back to my modern molecular genetics laboratory."

In college he spent seven months in Northern Borneo collecting plants and learning about plant diversity. "That was the first time I saw the giant rafflesiaceae. I thought they were cool, but I never thought that I would end up studying them."

###