Chinese scientists recently discovered ginkgo (or the maidenhair tree) fossils in Northeast China's Yi County, Liaoning Province.
The fossils, bearing reproductive organs, are believed to belong to the early Cretaceous period (about 120 million years ago), and the founding has filled up as long the vacancy as over 100 million years in the history of Ginkgo evolution.
Billions of years have gone by and dinosaurs once dominant on the earth can now only be found in the depth of strata in the form of fossils. Yet the ginkgo, which is of the same age with dinosaurs, is nowadays still living on the surface of the earth. Therefore, the studies of the classification and evolution of the plant, the "living fossil", have always been drawing great attention of the people.
In 1989, Chinese scientists found ginkgo fossils of 170 million years ago (in the early Jurassic period), the oldest and most complete of its kind known to people. During the century that followed, the world reports on ginkgo fossil discoveries, although plenty in number, due to lack of classification and evolution significance, most of them failed to explain how the ancient ginkgo evolved into today's kind, leaving a "blank" in the whole chain of evolution history.
The latest discovery by Zhou Zhiyan, an academician of the Chinese Academy of Sciences (CAS) with the CAS Nanjing Institute of Geology and Paleontology, and Zheng Shaolin, a researcher from Shenyang Institute of Geology and Mineral Resources under the Ministry of National Land and Resources, presents people a clear, full picture of the evolution process of the precious plant.
In an article published in the June 19, 2003 issue of Nature, the researchers report their findings of well-preserved fossil leaves and reproductive organs of ancient ginkgo trees of 120 million years ago. They revealed that ginkgo's reproductive structures at that time were more like those of the present-day ginkgo rather than those of the primitive Jurassic type, indicating that their morphology has taken a little change during the 120 million years.
(People's Daily June 24, 2003)
