permaculture

[mIEKAL aND <dtv@mwt.net>]

Fossilized plant may have been first flower

Thrived 125 million to 144 million years ago

May 3, 2002 Posted: 9:16 AM EDT (1316 GMT)

WASHINGTON (AP) -- The ancestor of all the grains, fruits and blossoms
of the modern world may have been a fragile water plant that lived in a
Chinese lake 125 million years ago.

The plant, called Archaefructus sinensis for "ancient fruit from China,"
is of a species never before seen and carries the clear characteristics
of the most primitive of flowering plants, said David Dilcher of the
Florida Museum of Natural History and the University of Florida.

"It is like the mother of all flowering plants," said Dilcher, co-author
of a study appearing Friday in the journal Science. "It changes our
whole impression of what is the oldest of all flowering plants."

 Botanists had long considered a woody plant from New Caledonia as the
most  ancient of flowering plants. Dilcher said the new discovery
precedes that magnolia-like species.

The discovery also suggests that flowering plants got their start as
herbs growing in shallow pools and were able to reproduce quickly, a
distinct advantage for survival, said Dilcher.

Archaefructus "was not a flashy flower," he said. The plant's flowering
part had no real petals, but acted only as a reproductive unit.

 "The reason we can say it is a flowering plant is that the seed is
enclosed inside of carpels of the fruit," said Dilcher. "That is primary
key." A carpel is the female part of a flower.

It is believed that flowering plants later developed colored petals and
fragrance and tasty fruits to help in reproduction. The showy,
good-smelling flowers attract insects to help in pollination and animals
eat the fleshy fruit of plants and help spread the seeds.

Dilcher said that Archaefructus apparently lived in clear, shallow
pools, with its  flowers and seeds extending above the water surface.
Its leaves probably  were submerged, he said, and the limbs were
partially supported by the water. The plant  rooted in the floor of the
lake.

Preserved by volcanic ash The best evidence of its waterlogged lifestyle
is that fossils of nine fish were found among the branches of the plant
in the slab of stone dug from the ancient lake, he said.

"The closest modern relative is probably the water lily," said Dilcher.

At the time the plant thrived, 125 million to 144 million years ago,
dinosaurs roamed the Earth and the early ancestors of mammals were tiny
creatures skittering among the rocks.

Dilcher said the lake where the plant lived was near erupting volcanoes.
The plant  was buried and preserved by a heavy fall of volcanic ash.

Finding the most ancient of flowering plants also sheds light on the
evolution of  humans, Dilcher said. "We co-evolved with flowering
plants," he said. "We depend today on flowering  plants  for our
survival, for food and fiber and building materials. The wheat, rice,
corn and all of the fruits that we enjoy are all flowering plants" that
may  have evolved from Archaefructus, Dilcher said.

Other experts in Science said it will require more examination of
before it is generally accepted as the most ancient of flowering plants,
but Peter Raven of the Missouri Botanical Garden in St. Louis said it
"may be the most significant flowering plant ever found."