This ancient giant bear looks cute, but actually...

The River of Life exhibition area of ​​the Shanghai Natural History Museum is a grand gathering of ancient and modern celebrity creatures. Many living creatures can find their ancient relatives here, such as peacocks and dinosaurs facing each other in the air, cute lions and saber-toothed tigers looking at each other from a distance...

So, can the national treasure giant panda and even all the eight living bear species find their ancestors here?

There are 8 living bear species, 6 of which are displayed on Bear Island of Shanghai Natural History Museum. Photo credit: Photo by the author

The answer is yes! Their predecessors are the giant short-faced bear (not the ancient polar bear!) and the cave bear next to it!

Left: Cave bear skeleton, right: Giant short-faced bear model Image source: Photographed by the author

The extinct giant "cute" bear

The giant short-faced bear* (Arctodus simu*) is an extinct ancient bear that lived in North America during the Pleistocene. The species name, simus, means very large. Indeed, weighing 900 kg, standing 1.7 meters tall at the shoulder when walking on all fours and more than 3.4 meters tall when standing on its hind legs, the short-faced bear was one of the largest prehistoric bears .

The giant short-faced bear in the River of Life exhibition area Source: Shanghai Natural History Museum

Even the largest polar bear in existence, which looks somewhat like it, has to call itself "little brother" in front of the short-faced bear. Polar bears are a species of bear with a large difference in size between the two sexes. An adult male polar bear can stand up to about 2.5 meters tall and weigh up to 798 kilograms, while an adult female polar bear is much smaller.

Unlike the common bears today, the giant short-faced bear not only looks like it has been enlarged, but its limbs also seem to have been stretched. With its tall stature and long legs, it can walk more quickly and agilely. However, its limbs are more suitable for long-distance walking rather than fast running and hunting.

"Short-faced" bear

It's not that his face is really short! It's also super fierce!

There are two species in the genus Short-faced Bear, namely the giant short-faced bear with a huge body and the slightly smaller short-faced bear with a small body. The giant short-faced bear evolved from the short-faced bear with a small body.

They all have the word "short-faced" in their names, but the skull of the giant short-faced bear is not short. It can be up to 52 cm long, longer than any other living bear. It's just that their snout is deeper, their nasal bones are shorter, and their muzzle is smaller in proportion to the entire head , so their face looks short. (In layman's terms, the muzzle is shorter)

Don't think that it is easy to bully because of its short and cute snout. People have long believed that the giant short-faced bear was mainly carnivorous and could even actively hunt large herbivores such as bison . Subsequent fossil isotope testing also found that meat did account for a high proportion of the giant short-faced bear's diet.

But tooth fossils show that they are omnivores like most modern bears. In addition to eating meat, they also eat a lot of plants. Juniper seeds were also found in the feces of short-faced bears found in South Dakota and Yukon. In addition, the proportion of meat and vegetarian food of short-faced bears living in different areas may be different.

We can imagine the life of the short-faced bear on the North American continent: with its large body, long legs, developed sense of smell and thick molars, the giant short-faced bear might roam the wilderness of northern North America, snatching prey or looking for carrion, and eating vegetarian food if it couldn't find meat .

Ancient short-faced family

If the giant short-faced bear is the prehistoric "King of the North", then the title of "King of the South" must go to the narrow-toothed South American short-faced bear ( Arctotherium angustidens ), also known as the fine-toothed giant bear, which is a bear larger than the giant short-faced bear. It stands nearly 4 meters tall and weighs 1,100 to 1,600 kilograms.

Narrow-toothed South American short-faced bear restoration image source: tumblr

Both the giant short-faced bear and the South American short-faced bear belong to the subfamily of spectacled bears (also called short-faced bears), which once dominated the entire Americas in prehistoric times.

The short-faced bear can be said to be one of the most terrifying predators that humans have ever faced. Why did these short-faced giant bears become extinct? The reasons may be complicated, and scientists are still unsure. One possible reason is that the temperature dropped sharply due to the Younger Dryas event (a period of rapid climate cooling that lasted about 1,300 years). The short-faced bears could not adapt to this sudden climate change and gradually became extinct. However, more fossil evidence is needed to draw conclusions.

Surviving today: The last short-faced bear

Compared with the ancient times when bears were numerous, there are only a few members of the Ursidae family, including 3 subfamilies, 5 genera and 8 species . They are giant panda, spectacled bear, brown bear, polar bear, American black bear, Asiatic black bear, sloth bear and Malayan bear. Except for the giant panda, which belongs to the subfamily Ailuropodinae, and the spectacled bear, which belongs to the subfamily Ursidae, the other 6 species of bears all belong to the subfamily Ursidae.

Although the short-faced bear has similar appearance features to the brown bear, its closest living relative is the spectacled bear . If you look closely, you can see that the spectacled bear also has a shorter face, and it is the only remaining member of the short-faced bear family.

Close-up of spectacled bear head Source: wiki

The spectacled bear, also known as the Andean bear, is a species of bear endemic to South America and the only species of bear still found in South America. They usually have distinct beige or ginger markings around their eyes, which makes them look like they are wearing a pair of glasses, hence the name spectacled bear. But not all spectacled bears have "spectacles" markings, and the pattern and extent of the light-colored markings on each bear are slightly different.

Spectacled bears like to eat plants, and the most common foods are cacti, bromeliads and various fruits in the forest.

Conclusion

Bears occupy an important position in human life and culture, and there are myths and legends about bears all over the world. It is understood that the International Union for Conservation of Nature (IUCN) has listed 6 species of bears as vulnerable species. The spectacled bear subfamily has produced giants such as the narrow-toothed South American short-faced bear and the giant short-faced bear. Now there is only one small species left, the spectacled bear. I hope everyone can pay more attention to and protect them.

Planning and production

Source: Shanghai Natural History Museum (ID: snhm01)

Author: Yang Mengxia Shanghai Natural History Museum Exhibition and Education Center

Reviewer: Huang Chengming, Researcher at the Institute of Zoology, Chinese Academy of Sciences

Editor: Zhong Yanping

Proofread by Xu Lailinlin