Chinese researchers have found the much-sought missing link between the ancient and modern plants from the 121-million-year-old stratum of the Yixian formation in northeast China.
Ginkgo, or the maidenhair tree, is considered a living fossil, as it was found to have existed early in the Jurassic period about 170 million years ago. However, a more than 100 million-year gap in the fossil record since the Jurassic period has hindered a full understanding of its evolution.
Recently ZHOU Zhiyan, a CAS member with the CAS Nanjing Institute of Geology and Palaeontology, and ZHENG Shaolin, a researcher from Shenyang Institute of Geology and Mineral Resources under the Ministry of National Land and Resources, found the much-sought missing link between the ancient and modern plants from the 121-million-year-old stratum of the Yixian formation in northeast China.
In an article published in the 19 June 2003 issue of
Nature, the researchers report their findings of well-preserved fossil leaves and reproductive organs of ancient Ginkgo trees 120 million years ago. They reveal that Ginkgo's reproductive structures at that time were more like those of the present-day Ginkgo biloba than those of the primitive Jurassic type, indicating that their morphology has changed little for over 100 million years ago.