TULSA, Okla. (AP) -- A University of Tulsa biology professor is
helping get to the root about how Earth's 1 million plant species
Mark Buchheim, who studies the evolution of green algae,
proposed a collaborative research project to fill gaps in the
world's knowledge and provide a more precise evolutionary tree of
the Earth's plants.
The findings were released recently and provide the most
complete "tree of life" to date, overturning many long-standing
theories about how the world's plant species are related to one
The group's research suggests that a small, rare shrub found
only on a few South Pacific islands is the closest living relative
of the Earth's first flowering plant. This means the shrub is the
most primitive flowering plant on earth, according to the research.
"It doesn't necessarily mean that this plant is a living
fossil, as some people have suggested," Buchheim warned.
But the find apparently solves Charles Darwin's "abominable
mystery," which was the question of which plant, or plants, began
flowering about 135 million years ago.
The research also suggests that a single, green "Eve" is the
mother of all the green land plants living today. This find
overturns the previous theory that today's plants have several
"I think it's a big deal," Buchheim said.
Buchheim got a government grant for the project and recruited
some plant specialists to work on it. Eventually, more than 200
scientists from 12 countries worked on the five-year project that
was named "Deep Green."
The study found that fungi -- including yeast and mushrooms -- are
more closely related to people than to the green plants. Although
it seems counterintuitive, the idea has been around for about six
The researchers found that plants did not go directly from the
sea to land as previously believed. Instead, plants spent millions
of years stewing around in fresh water, preparing for the dry,
harsh existence of life on land.
"This find contradicts what is taught in every text book in
America," Brent Mishler, a spokesman for the "Deep Green"
project, said in a news release.
The scientists concluded that there are at least three separate
plant kingdoms rather than one, again contradicting what is taught
from text books.
Buchheim said the study may help botanists who are looking for
medicinal compounds that occur in rare plants. By using the revised
"Tree of Life" scientists can find that plant's closest relatives
and see if they have the medicinal compound.