Maotianshan Mountain Shales has become one of the first national geological parks in China and a base of scientific study and travel.

帽天山动物化石群 Maotianshan Mountain Shales

Located in the east of Chengjiang County, 8 kilometers from the seat of the county, Maotianshan Mountain looks like a big hat, hence the name. The mountain is famous for the ancient fauna fossils discovered by two biologists of Chinese Academy of Science in 1984. The fossils here were proved to be the zeolites of the Cambrian Period, 5.3 hundreds million years ago. The discovery made a sensation in the international paleobiological circle because the intact and well-preserved fauna individuals in the fossils offered a lot of valuable materials for paleobiological research. Therefore, the discovery is acclaimed as “one of the greatest discoveries in the 20th century” and “one of the three wonders of the early organic evolution instances in the history of the earth” ( The other two wonders are Ediacaran Zeolites in Australia and the Burgess Zeolites in Canada.). At present, a fauna fossil museum has been established in Maotianshan Mountain for scientific research, science popularization, and sightseeing.

Basic Information

Geographic location: At the east coast of Fuxian Lake, Chengjiang County
Scenic status: Maotianshan Mountain Zeolites is regarded as the “Holy Land of Paleobiology” in international academic, and “the three wonders of the early organic evolution instance in the history of the earth”. It is the first national geological park in China
Tour time: 1 day

Key Points

The significance of the fossils in earth history, the overview of Maotianshan Paleozoic Fossil Site, life explosion, Fuxianhuia, Yunnanozoon, significance of the discovery

Maotianshan Paleozoic fossil zone (Maotianshan Fauna) is located on the east coast of Fuxian Lake, Chengjiang County of Yunnan Province. It is 70 kilometers from Kunming, the capital of Yunnan province, and it takes about 2 hours to drive there.

The whole Paleozoic fossil zone is in the shape of a snake, winding for about 20 kilometers long and 4.5 kilometers wide. The depth of covering layer is over 50 meters. The delineated protected area is 18 square kilometers and the core protected area 1.2 square kilometers.
So far, there are more than 30 fossil occurrences being discovered and over 30,000 fossil pieces sampled. Through study and identification, the scientists have found more than 100 kinds of Paleozoic fossils which belong to 40 categories, covering all kinds of the modern living beings. Furthermore, many kinds of extinct animals living in remote antiquity are also discovered. They are beyond the available animal classification system, and the naming of these animal fossils is made according to the discovering sites such as Fuxianhuia, Maotianshania, Yunnania and so on.

The scientific significance of the fossils in the earth history

Maotianshan animal fossil group of Chengjiang County in Yunnan Province is the most important link in the life explosion during Cambrian Period.

In most people’s eyes, these fossils are just some animal bones existing in the stones that human being can usually find in the stones of the house bases and tombs. They are not that special, but wait! What year were these fossil animals in the stone living? What did they look like? What is the scientific significance of these fossil animals in the history of the development of the earth?

The earth has a history of 4.6 billion years and it has experienced several geological periods. Generally, people divide the time of the earth evolution into several geological development eras such as Archaeozoic Era, Proterozoic Era, Paleozoic Era, Mesozoic Era and Cenozoic Era. The Cambrian Period is a geological time ranging from 540 million to 510 million years ago in the Paleozoic Era. Burgess Zeolites (animal fossil group) of the Mid Cambrian period discovered in Canada in 1909 caused a sensation throughout the world. In 1947, Ediacaran Zeolites (animal fossil group) of the late Precambrian period was discovered in Australia. There is a time interval of 10 million years between these 2 fossil groups and the (sudden changes) evolution of these 2 animal groups in 10 million years is hard to be proved by materials. The animal fossil group discovered at Maotianshan Mountain in Chengjiang County, Yunnan Province, is just between the 2 above-mentioned animal fossil groups and it becomes the most important link in the life explosion of Cambrian Period.

On April 17, 1987, Nanjing Geological Paleontology Institute of China Science Academy announced at the press conference in Nanjing a world shocking news —— the animal fossil group discovered in Chengjiang County of Yunnan Province is 530 million years old, the exquisiteness of the fossils and their category varieties are rare in modern paleontology research history of the whole world.

The study of the Paleozoic Fossils of the Cambrian Period in Yunnan covers a long history

In the 1950s, 1960s, and 1970s, several phosphate deposits were developed and mined around Kunming, such as Kunyang Phosphate Deposit, Anning Phosphate Deposit, Lufeng Yangjie Phosphate Deposit and Chengjiang Phosphate Deposit. Many Paleozoic fossils were discovered in these phosphate mine areas. The geological scientists of that time undertook a detailed study of these Paleozoic fossils. Scientists such as Mr. Li Xiji (former advanced geo-engineer of Yunnan Geology Research Institute, former general geo-engineer of Yunnan Geology and Minerals Administration and the former Vice Chairman of the Science Association of Yunnan Province), Mr. Luo Huilin (the then senior geo-engineer of Yunnan Geology Research Institute), Mr. Jiang Zhiwen (the then senior geoengineer and former director of Yunnan Geology Research Institute) and Mr. Chen Liangzhong (Senior geo-engineer of professor level), had made detailed and meticulous study of the Paleozoic fossils in Kunyang Phosphate Deposit and others in 60s, 70s and 80s, and many scientific achievements were made from their study.

Mr. Luo Huilin, Mr. Jiang Zhiwen and other geological scientists of Yunnan Province were invited to Russia, USA, Canada and other countries for international academic exchanges. Their research articles on The Cambrian Paleontology Study in Kunyang Group drew great attention from the world geological academic field and were highly appraised. The research achievement on the Cambrian Geological Standard Section in Kunyang Phosphate Deposit was their important contribution to the scientific research of Yunnan. The World Geological Association set up a gold nail on the Cambrian geological standard section in Kunyang Phosphate Deposit in 1982 to confirm its status in the world geological study. That has laid a foundation for further research on Paleozoic fossils in Kunyang Group.

Progress in the 1980s

In June 1984, Mr. Hou Xianguang, a graduate from Nanjing Geological Paleontology Institute of China Science Academy, Jiangsu Province, came to Maotianshan Mountain to search for the fossils from Cambrian Period.

About 3 pm on July 1st, 1984, Mr. Hou Xianguang was busy on exploration work. He suddenly trod on a piece of loosening stone formation and a piece of fossil appeared from the loose stone. It was in unique shape and well preserved. Mr. Hou Xianguang identified the fossil with his professional knowledge and knew that was a piece of invertebrate animal fossil in the early Cambrian period. He kept on searching and found 3 important fossils on that day. Further identification showed that the 3 fossils discovered were respectively Naraoia, Branchiocaris-yunnanensis (Yunnan Saixiachong) and Jianfengia fossils.

In the days followed, Mr. Hou Xianguang found a lot of Paleozoic fossils of the same period such as arthropod, medusa (jellyfish) and helminth (worm) and so on. After going back to Nanjing, Mr. Hou, in collaboration with his supervisor Professor Zhang Wentang, wrote a research article entitled “The Discovery of Naraoia in Asian Continent”. In this article, they named the animal fossils discovered in Chengjiang as “Chengjiang Animal Group (Chengjiang Fauna)”.

Trip to Maotianshan Paleozoic Fossil Site

One hour’s drive away from Chengjiang city proper is Maotianshan Mountain Cambrian Paleozoic Fossil Site ——“Chengjiang Maotianshan Museum of Cambrian Paleozoic Fossils”. The museum possesses a great collection of most Cambrian Paleozoic fossils discovered in this area. In the past 20 years or so, the geological scientists and paleontologists have found more than 180 kinds of Paleozoic fossils in Chengjiang through their meticulous and sustained efforts. Eighty percent of these fossils are newly discovered and more than 20 kinds of them are print fossils and excrement fossils. The Paleozoic fossils at the Maotianshan Mountain cover almost all kinds of modern oceanic animals. That is to say, almost all the modern oceanic animals could find their remote ancestors in this area.
Yunnanozoon, the remote ancestor of human being, was discovered for the first time in Chengjiang

Life explosion

Paleontology study shows that it has been 3.8 billion years since life appeared on the earth. Before Cambrian Period or 540 million years ago, life only existed in simple shapes of algae and bacterium in the ocean. Since Cambrian Period, many aquatic animals produced in the ocean, and they evolved especially fast from unicellular algae and bacterium to a multicellular organism in simply a little more than 10 million years. Chengjiang animal fossil group (Chengjiang Fauna) recorded the whole process of the life evolution of this special period. In comparison with 3.8 billion years, 10 million years is one minute in a single day. For this reason, scientists called this phenomenon of the quick life evolution “life explosion”.
In the museum, there are displays of the newest achievement of fossil restoration done by Prof. Chen Junyuan in recent years. They are vivid presentations of the passed away bodies only left in the fossil samples and those are the 530 million years old oceanic panoramic views which had disappeared early in the geological evolution. These living beings are with peculiar postures and gorgeous colors.

Fuxianhuia——The remote ancestor of insects

Fuxianhuia is the peculiar fossil in Chengjiang animal fossil group (Chengjiang Fauna). It belongs to the relatively primitive type of the real arthropod. The adult body is 10 centimeters long and with 31 body segments. The external skeleton is composed of 3 parts as head, thorax, and abdomen. The numbers of its segments are not the same on the back and abdomen. It is similar to the shrimp (zhixia) of the Devonian period; zhixia is the ancestor of the modern insect. This indirectly suggests that Fuxianhuia is the remote ancestor of insects.

Presumably Naraoia taijiangensis, Order Nectaspida, Family Naraoiidae, 12mm front to back, dorsal view.

Magical coelenterate —— Ctenophora (Medusa jellyfish)

Ctenophora (medusa jellyfish) is a carnivorous coelenterate. At present, the Ctenophora discovered in Chengjiang is only in a term of description and the research for its evolutionary significance is not clear yet. There are pleats on the body similar to ladders and the body radiates symmetrically. This is unique for animals in the ocean because it is very hard to keep balance for animals with symmetrical radiation. It is harder for them to catch food. A stony balance ball grew on the top of its body to keep balance. Modern medusa is called “Sea walnut” and it is the oldest invertebrate animal.

A Heliomedusa orienta lampshell, Order Paterinata, Family Mickwitziidae, 15mm across

Amplectobulua —— Anomalocaris saron in the Cambrian ocean

Anomalocaris is an exterminated big invertebrate animal. The fossil shows that its mouth had more than ten rows of teeth of 25 centimeters in diameter. Its excrement fossil is 10 centimeters long and 5 centimeters in diameter. From this, it can be inferred that its body can be over 2 meters long.

Anomalocaris was first discovered in Canada. The discovered part was only a piece of a fossil of the fore claw. It was mistakenly considered to be the tail. In 1994, Chinese scientists discovered the complete Anomalocaris fossil at Maotianshan Mountain and since then the mistake was corrected. The so-called “tail” is actually its claw.

The scientists found the remnants of the small shell animals from the excrement fossil of Anomalocaris fossil, and that is to say, it was a carnivorous animal in the Cambrian ocean and it was the lord of the ocean world and the final consumer of the ocean food. The discovery of Anomalocaris indicated the real existence of a complete food chain in the ocean.

Maotianshan Shales
Leanchoilia illecebrosa, Order Leanchoiliida, Family Leanchoiliidae, 19mm front to back, lateral view

Yunnanozoon: the remote ancestor of human being

Yunnanozoon has a body shape as a worm. It is usually 3 centimeters to 4 centimeters long, but the longest could be 6 centimeters. In 1995, Prof. Chen Junyuan and some other research fellows found that it had 7 pairs of gills with which it could breathe and keep food in its oral cavity. This is the important feature of the chordate and the idea that “Yunnanozoon is the chordate” was put forward.

The primitive notochord of Yunnanozoon is the predecessor of the vertebra. It was rather soft and easy to be harmed by outside forces. The primitive notochord of Yunnanozoon was similar to the soft material in vertebra today. The nerve unit of the body concentrated on the notochord and the sense of the limbs spread to the whole body through notochord. The emergence of the notochord raised the ability of the body control and the adaptation to the environment. The discovery of Yunnanozoon had proved the origin of the vertebrate in Chengjiang animal fossil group (Chengjiang Fauna) and this was a great breakthrough in the history of life evolution.

Chinese scholars have published several research articles in Nature about their research achievement on Yunnanozoon. In 1995, the article “A Way from Yunnanozoon to You” was published in New York Time. One quote from this article reads, “If Yunnanozoon had died young, the central nerve of the animals would have never been developed. Then the earth would be silent and cold like the moon in the remote space”.

Dreamlike organism: Hallucigenia Worm

Hallucigenia belongs to Labopodia. It has a large head and 7 pairs of strong long thorn growing obliquely on the back-side of the body. The first discovery was in Canada. It was the most famous animal of the Cambrian Period.

Because of the poor preservation of the original fossils, the British paleontologist Mr. Morris mistakenly took the 2 pairs of thorns as walking legs and took the walking legs as the ornaments when he saw the 2 pairs of thorns regularly distributed on the body in 1997. He thought such a weird organism “only can be dreamed of in a dream”, therefore, he named Hallucigenia “Weird Worm”.

A discovery that shocked the world

The discovery of Maotianshan Paleozoic fossil group (Chengjiang Fauna) and its study achievement surprised the whole world. On April 23, 1991, US New York Time introduced the discovery of Maotianshan Paleozoic Fossil group on the first page and pointed out that “The discovery of China Maotianshan is one of the most amazing discoveries of the century”.
In January 2001, Science published an article with a general introduction about the status of China paleontology study and said that Yunnan Chengjiang fossil has advanced the emergence of vertebrate for 60 million years. These fossils helped paleontologists to evidence the Cambrian life explosion 530 million years ago.

An academician of British Royal Science Academy thought that Chengjiang Fauna “is forever a high building of science” while New York Time claimed it “one of the most amazing discoveries of the 20th Century”.

US Science Press commented even more vividly: “the paleontologists are incomparably elated for these fossil evidence for they were probing the origin of the organism in the darkness of the early earth and working hard so long without explanation but despair”.

Fossils images:

Dwergenpaartje, https://en.wikipedia.org/wiki/Chengjiang_County