Records of an Explosion and a Whimper
The Nanjing Institute of Geology and Palaeontology (NIGPAS) is a primary caretaker for fossils from two of the most significant moments in Earth's history. The institute's collections hold definitive records of life's explosive beginnings and its most devastating collapse. Researchers here study the Chengjiang biota, a fossil deposit from Yunnan province dated to 518 million years ago. These fossils record the Cambrian explosion, a period when nearly all major animal body plans appeared in a geologically short time.
The preservation at Chengjiang is so exceptional that it includes soft tissues, which are rarely fossilized. This allows for detailed study of creatures that seem alien today. The collection includes specimens of Anomalocaris, a large swimming predator with spiny appendages, and early vertebrates like Haikouichthys. The fossils document a complete marine community, showing the complex ecosystem that emerged during this burst of evolution. The discovery of the Chengjiang fossils in 1984 by a NIGPAS paleontologist was a significant finds of the 20th century. The institute's work on this fauna earned a National Natural Science Award in 2003.
The Great Dying's Ground Zero
The institute also curates research on the Permian-Triassic extinction, the most severe mass extinction event known. This cataclysm, which occurred about 252 million years ago, eliminated over 90% of marine species and 70% of terrestrial vertebrate species. The official global benchmark for this event, the Global Stratotype Section and Point (GSSP), is located at a site in Meishan, not far from Nanjing.
Research on this section allows scientists to pinpoint the exact boundary in the rock layer between the Permian and Triassic periods. The prime marker for the boundary is the first appearance of a tiny tooth-like fossil from a conodont animal called Hindeodus parvus. Studies of the Meishan section, supported by NIGPAS, confirm the extinction was a sudden event, coinciding with a sharp change in carbon isotopes in the rock. This evidence shows massive volcanic eruptions in the Siberian Traps as the likely cause, which triggered catastrophic climate change and oceanic anoxia. Despite the global devastation, recent research from the institute has identified a "life oasis" in China's Turpan-Hami Basin, where a terrestrial plant community survived the extinction event largely intact, a refuge for life.