From being raised in the palace to being on the verge of extinction today, what has the rhino family experienced?

Produced by: Science Popularization China

Author: Lv Zelong (Student at Institute of Zoology, Chinese Academy of Sciences)

Producer: China Science Expo

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In October 2024, new fossil material from the Late Miocene (eight to nine million years ago) was unearthed in Myanmar, including rhinoceros fossils that were closely related to the now critically endangered Sumatran rhinoceros ( Dicerorhinus sumatrensis ) and Javan rhinoceros.

Some of the fossils found in this study

(Image source: Reference 1)

Javan rhinoceros

(Photo source: WWF official website)

Some friends may not be familiar with the names of these two rhinos, and may think that they are special products of Sumatra and Java. But in fact, the ancestors of these two rhinos may have originated from the Asian continent. They are recorded in ancient Chinese documents. "Without the wings of a phoenix, we have a spiritual connection" and "Holding a Wu spear and wearing a rhinoceros armor" are talking about them. They also appear in stories such as "Journey to the West" and poems by Tang people.

What is the relationship between these newly discovered rhino fossils and today's Javan and Sumatran rhinos? What evolutionary relationships do they reveal? How do today's rhinos live?

Indian rhinoceros and Asian elephant specimens

(Photo source: taken by the author at Tianjin Natural History Museum)

Family tree and some relatives

All extant rhinoceroses belong to the family Rhinocerotidae of the order Perissodactyla, but at the genus level, the Javan rhino and the Indian rhino ( Rhinoceros unicornis ) are both from the genus Rhinoceros, while the Sumatran rhino is from the genus Dicerorhinus.

Some of the fossils found this time were classified as Dicera based on morphological observations, such as a fossil of the talus (equivalent to the ankle bone) of a relative of the Sumatran rhino. The fossils of the Unicornus rhino include a large number of forelimb bones, from the humerus to the basal bone. In addition, there is a fossil of the talus that is similar to the Javan rhino.

Note: The Indian rhino and Javan rhino are also known as the Greater One-Horned Rhino and Lesser One-Horned Rhino, respectively. The Sumatran rhino is also known as the Asian Two-Horned Rhino. The other two existing rhinos, the Black Rhino ( Diceros bicornis ) and the White Rhino ( Ceratotherium simum ), are also from different genera.

Some localities of the Dicera fossil record during the Miocene and later Pliocene and Pleistocene

(Image source: Reference 1)

Indian rhinoceros

(Image source: theethicalist official website)

After the end of the late Miocene, members of the two genera, One-horned Rhinoceros and Two-horned Rhinoceros, continued to exist and continue to occupy the warm areas of Asia, at this time several of their other distant relatives belonging to the True Rhinoceros family also became active.

Three to four million years ago, the Tibetan woolly rhinoceros ( Coelodonta thibetana ) appeared on the Qinghai-Tibet Plateau and differentiated into the Nihewan woolly rhinoceros and the last woolly rhinoceros ( Coelodonta antiquitatis ) in northern Eurasia. Based on the corresponding genome research, it was found that they are related to the existing Sumatran rhinoceros and have relatively long red hair on their bodies.

Tibetan woolly rhinoceros fossil

(Photo source: taken by the author at the China Paleozoological Museum)

Sumatran rhinoceros

(Photo source: natureworldnews official website)

When the woolly rhinoceros finally occupied the northern border of the Pleistocene, a group of Elasmotherium with huge horns and weights comparable to today's white rhinoceros also appeared in Siberia and other places. Their relationship with all existing rhinoceroses and woolly rhinoceroses is relatively distant, but they are also members of the family Rhinoceros. The ancestors of these "unicorns" originally had very small or no horns, that is, early members of the Elasmotherium. Later, during the evolution process, relatively large nose horns appeared, and then the nose horn and the frontal horn gradually merged into one, the head became thicker, and the body size gradually increased.

The old version of the restoration of the Eurytherium, some studies also believe that their horns were not so long

(Image source: newdinosaurs official website)

At the junction of the south and the north, there is another relative of the Sumatran rhino, the Stephanorhino, whose long legs facilitated feeding on relatively tall shrubs and leaves. Fossil records in China show that Stephanorhino was widely distributed, including the three northeastern provinces, Beijing, and many places in the south of the Yangtze River Basin. Nesorhinus rhinoceros lived in the Philippines and Taiwan Province of China.

Restoration of the Stephanorhinus kirchbergensis

(Image source: dinosaurhome official website)

Insular rhinoceros fossils from Taiwan

(Photo source: Nanyang Technological University official website)

Life in the Pleistocene

The Pleistocene was a period of active glaciation, the longer of the two Quaternary glacial epochs that make up Earth's history. During this period, various species of rhinoceros flourished in different regions, including the one-horned and two-horned rhinoceros. Meanwhile, animals such as giant pandas and giant apes roamed the southern lands. The Fusui one-horned rhinoceros was one of the species that appeared during this period.

The fossils of Fusui rhinoceros ( Rhinoceros fusuieneis ) were discovered in Fusui, Guangxi and other places, and were officially named in 2014. In the summer of 2024, new fossil materials of Sumatran rhinoceros were discovered in Zunyi, Guizhou—a fossil with obvious skull and teeth. Although Sumatran rhinoceros fossils have been found in many places before, such as Kaiyuan, Yunnan and Liucheng, Guangxi, the fossil record of Sumatran rhinoceros is still relatively scattered compared with woolly rhinoceros.

Javan rhinoceros-like fossils from Guangxi

(Image source: Reference 6)

New Sumatran rhinoceros fossil

(Photo source: WeChat Live Zunyi)

Javan rhinoceros fossils have been found in Chongqing and other places, and there are also records in Chongzuo, Guangxi and other places. Some people speculate that today's Javan rhinoceros may be the descendants of Fusui rhinoceros. Indian rhinoceros fossils are relatively rare in China, but based on the morphological identification of fossil teeth, some people speculate that they may be distributed in Xichou, Yunnan and other places. The academic community speculates that the Indian rhinoceros may be the descendant of the Sivalensis rhinoceros family, whose evolutionary center is actually in the Indian subcontinent.

Note: The Chinese rhinoceros ( Rhinoceros sinensis ) of the genus Rhinoceros has also been discovered in southern China and other places, with many fossil specimens, but some scholars believe that it is an invalid species, and those fossils considered to be "Chinese rhinoceros" are likely to be other members of the genus Rhinoceros.

Fossils believed to be from the Chinese rhinoceros

(Image source: Reference 6)

The three rhinos have slightly different eating habits. Today, the Sumatran and Javan rhinos prefer to eat leaves, while the Sumatran rhinos also eat fruits such as mangosteen. The Javan rhinos also use their flexible upper lips to grab branches and small trees when eating young leaves, while the Indian rhinos eat more grass. The main difference between the Indian rhinos and the Javan rhinos is that the latter has a saddle-shaped ring on the back of its neck.

Javan rhino painting (note its neck)

(Image source: Britannica)

Conflict and Protection in the Age of Civilization

After the end of the Pleistocene, woolly rhinoceros and other members became extinct, while Indian rhinoceros, Javan rhinoceros and Sumatran rhinoceros survived and were preserved in ancient documents and relics. When Mozi visited the State of Chu, he mentioned the herds of elk and rhinoceros in the area. Qu Yuan described the Chu soldiers using rhinoceros leather armor for defense. The "Wu Yue Chunqiu" also recorded that King Goujian of Yue defeated King Fuchai of Wu with an army wearing rhinoceros armor. Rhinoceros skin is considered an excellent defensive material because of its thick keratin layer.

As the climate in China changed during the Zhou Dynasty and thereafter and human hunting activities increased, the distribution and number of the three rhinoceroses decreased significantly. Mencius recorded that King Wu of Zhou "drove away tigers, leopards, rhinos, and elephants."

Sumatran rhinoceros

(Photo source: taken by the author at the National Museum)

During the Tang Dynasty, there were still rhinos south of the Yangtze River, and some were even domesticated in the palace. Bai Juyi's poems recorded that rhinos from Southeast Asian countries were sent to Guanzhong and died of cold. In the Song Dynasty and later, with the increase in population and the shift of economic center to the south, the development of mountains also put rhinos at risk. During the Ming and Qing Dynasties, the climate became colder, and there was even a small ice age. With "all the mountains barren", rhinos in China only existed in parts of Yunnan Province.

Artifacts carved from rhino horns

(Image source: bidamount official website)

In the mid-20th century, wild rhinos disappeared in the Red River region of Yunnan Province, China. In the following decades, Javan rhinos and Sumatran rhinos in Asia, such as Vietnam and Thailand, also faced a crisis. In 2010, the last Javan rhinoceros in Asia became extinct in Vietnam, and in recent years, the Sumatran rhinoceros in Malaysia has also disappeared. Indonesia has become the last habitat of the Sumatran rhinoceros and Javan rhinoceros, while the Indian rhinoceros only exists in India and Nepal.

Javan rhinoceros distribution range, light green is the historical distribution area, dark green dots are the current distribution area on Java Island

(Image source: WWF)

The Indian rhinoceros, which is heavily protected in its habitat in northeastern India and Nepal, where thousands remain, has been particularly lucky in its recovery, from fewer than 200 to nearly 4,000.

Protected Indian rhinoceros

(Image source: WWF)

Sumatran rhinoceros

(Photo source: destepti.ro)

The Javan rhino is in a tough situation. Its population has dropped sharply, with less than 100 left. It lives in Ujung Kulon National Park, and more than 20 were reported lost this spring. This is attributed to the madness of poachers for rhino horns. But in fact, the main component of rhino horns is keratin, the same as hair and nails, and there is no special component. People nowadays do not need rhino horns for medicine. The Sumatran rhino is also endangered, with less than 100 left. The status of its population in the eastern part of Borneo Island in Indonesia is still unclear.

Javan rhinoceros in the wild

(Photo source: CBS News)

The good news is that some zoos and Sumatran rhino sanctuaries are working hard to promote the breeding of Sumatran rhinos, and the poaching of Javan rhinos mentioned above has also been discovered and controlled by the Indonesian police. The monitoring and conservation of rhino populations is also ongoing. The public should stop being crazy about rhino horn medicines, get familiar with and understand these creatures that once roamed the land of China, and don't wait until they are lost before cherishing the "rhinos".

(Note: Latin parts in the text should be italicized)

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