160 million-year-old petrified ginkgo wood, discovered by Wang Yongdong and his research group.[Photo: huanqiu.com/Wang Yongdong]
Petrified gingko wood that is at least 160 million years old has been discovered in the Beipiao area of Liaoning province in northeastern China.
The discovery was made by a group led by Wang Yongdong, a researcher from the Nanjing Intstitute of Geology and Palaeontology, Chinese Academy of Sciences.
"The cell structure of the 160 million-year-old ginkgo wood is nearly the same as it is now. It could be the oldest one among those which have been discovered." said Wang.
"The discovery could be meaningful to study the evolution of ginkgo plants and restore the Paleoenvironment of the Jurassic Period," he added.
Paleontologists have discovered many ginkgo leaf fossils which are 250 million years old. But fossils of ginkgo tree stalk, or petrified ginkgo wood, are rarely discovered and thus are very precious, according to Wang.
The oldest known petrified ginkgo wood discovered previously was dated at 120 million-year-old, or the early Cretaceous Period. Wang's discovery is 40 million years older.
Further, study shows that the leaf stomata density of ginkgo trees from the Jurassic Period is much smaller than it is now, which contributed to the extreme high levels of carbon dioxide during the Jurassic Period, quadrupling the present level.
Wang and his group first made their discovery six years ago. Findings have now been published in Scientific Reports, an online, open access journal from the publishers of Nature.