- The Washington Times - Friday, May 3, 2002

AGENCE FRANCE-PRESSE

The earliest flower fossil ever discovered, in northeastern China, is at least 125 million years old and suggests that modern flowers have their origins under water, according to a study published today.

The fossils were of underwater flowers and provided the first clue as to how flowering plants evolved, said David Dilcher, a paleobotanist at the University of Florida who published his discovery in Science magazine.

Collected from a sandy-colored slab in a fossil-rich area northeast of Beijing, the compressed plant was about 20 inches high with thin stems stretching upward and its seed organs extending above the water.

Its seeds probably were carried by the currents to shallow waters, where they germinated, Mr. Dilcher said.

The flowering plant probably grew in a shallow, sweet-water lake shared by dinosaurs and other creatures of the lower Cretaceous Period (63 million to 136 million years ago), but its origins could go as far back as the Jurassic Period (205 million years ago).

"The mysteries of the origin and radiation of the flowering plants remain among the greatest dilemmas facing paleontology and evolutionary biology," said William Crepet, head of the department of plant biology at Cornell University.

"This fossil represents the first evidence of an angiosperm that is basal to all other angiosperms, yet that does not fit within any modern taxonomic group of angiosperms. This makes it one of, if not the most, important fossil flowering plant ever reported," he added.

Angiosperms are flowering plants having seeds produced within a closed pod or ovary such as a fruit.

The fossil was discovered by Chinese farmers who gave it to one of the co-authors of the research paper. It is more complete than an earlier flower fossil found in the same region four years ago that Mr. Dilcher also studied.

"After having only a fragment and trying to imagine what the whole plant was like, it was a great surprise to find leaves typical of a plant that lived underwater with characteristics very unique to flowering plants at such an early age in their history," Mr. Dilcher said.

"This raises the question of whether flowering plant evolution happened on water or on land," he stressed.

Fish fossils mixed with the plant fossils in the slab provided other clues about the flower's underwater habitat. The flower fossil represents a new family of plants, the researcher said.

Mr. Dilcher, his colleague Ge Sun, a geologist at Jilin University in Changchun, China, and other researchers have proposed "Archaefructaceae" as the new basal angiosperm family for this ancient specimen.

"What's spectacular about these fossils is that all parts of the plant are present, including the roots, leaves and reproductive organs," Mr. Dilcher said.

LOAD COMMENTS ()

 

Click to Read More

Click to Hide