Tag Archives: Pandas

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Europe’s last pandas were giant weaklings who couldn’t even eat bamboo

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An artist’s interpretation of the new species of European panda. (Image credit: © Velizar Simeonovski, Chicago)

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A pair of fossil teeth in a museum collection recently revealed when pandas last roamed Europe. 

When researchers examined the teeth, which had been kept in storage for around 40 years, they discovered that the fossils belonged to a never-before-seen species of ancient European panda. The newfound species, which is a close relative of modern giant pandas, roamed the continent around 6 million years ago and was likely the last of Europe’s pandas. 

The teeth — an upper canine and an upper molar — were originally unearthed during the late 1970s from a site in northwestern Bulgaria, but they ended up in storage at the Bulgarian National Museum of Natural History in Sofia. The teeth were never properly cataloged, and as a result they were left untouched for decades. But when museum staff recently stumbled upon the unusual teeth, they decided to investigate further.     

After analyzing the teeth, researchers realized that they belonged to an ancient European panda, but the fossils were unlike any other teeth from panda species previously identified in Europe. Most species of European pandas had smaller teeth than modern giant pandas (Ailuropoda melanoleuca), meaning they were probably much smaller than their modern-day cousins. But the new species, which has been named Agriarctos nikolovi, had much larger teeth than was usual for European pandas, so it was most likely similar in size to today’s giant pandas. The teeth also date to much more recently than other European panda fossils, some of which date back to more than 10 million years ago, suggesting that A. nikolovi was likely the last panda species to live on the continent.

“This discovery shows how little we still know about ancient nature,” study co-author Nikolai Spassov, a paleontologist at the Bulgarian National Museum of Natural History, said in a statement (opens in new tab). The fact that the newly described species came from a specimen found in the 1970s also  “demonstrates that historic discoveries in paleontology can lead to unexpected results, even today,” Spassov said.

Related: The oldest DNA from giant pandas was just discovered in a cave in China 

Despite the size similarities between A. nikolovi and living giant pandas, the newly described species “is not a direct ancestor of the modern genus,” Spassov said. But “it is a close relative.” However, the new species likely lived in a very different habitat to today’s pandas, he added. 

The fossilized teeth were originally found in coal deposits, which had partly tinted the bears’ chompers black. The composition of the coal at the site suggests that the area was once a swampy forest. This means that A. nikolovi may have had a much more varied diet than modern pandas do, feasting on a range of soft vegetation rather than exclusively on one type of plant, such as modern pandas’ food of choice: bamboo. 

Interestingly, giant pandas’ digestive systems appear to be capable of processing meat, like other bears do, but they nonetheless stick to a strictly vegetarian diet. Prior research has suggested that giant pandas switched to a diet of bamboo because they were outcompeted by other bears, according to the statement. The researchers think A. nikolovi may also have faced similar evolutionary pressures to adopt a vegetarian diet, as its teeth are much weaker than those of modern pandas, which means they could probably not even chomp through bamboo, let alone something as hard as animals bones. 

A. nikolovi likely had a vegetarian diet because its teeth were weaker than those of modern giant pandas, who eat only bamboo. (Image credit: Shutterstock)

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The study authors also suspect that A. nikolovi may have eventually been wiped out because climate change affected their habitat and diet.

“It is likely that climate change at the end of the Miocene epoch [23 million to 5.3 million years ago] in southern Europe had an adverse effect on the existence of the last European panda,” Spassov said. The researchers suggested that A. nikolovi may have been especially vulnerable to an event that unfolded around 6 million years ago: the “Messinian salinity crisis,” when the Mediterranean Sea almost completely dried up, which had serious repercussions for terrestrial ecosystems. The ancient panda’s swampy forests likely became much drier and warmer, making it harder for plants to grow and likely starving the pandas, according to the statement.  

The team remains uncertain about how exactly A. nikolovi and other extinct European pandas are related to giant pandas and ancient Asian pandas. It is currently unclear if pandas first originated in Asia and migrated to Europe, or vice versa. However, the researchers suspect that a European origin for pandas is more likely because fossil evidence shows that “the oldest members of this group of bears were found in Europe,” Spassov said. But as the new fossils belong to the youngest of Europe’s long-gone pandas, they will probably not shed light on this particular mystery, the scientists reported. 

The study was published online July 31 in the Journal of Vertebrate Paleontology (opens in new tab).

Originally published on Live Science.

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Giant Panda’s “Amazing” Feature Developed at Least Six Million Years Ago

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An artist reconstruction of Ailurarctos from Shuitangba. The grasping function of its false thumb (shown in the right individual) has reached to the level of modern pandas, whereas the radial sesamoid may have protruded slightly more than its modern counterpart during walking (seen in the left individual). Credit: Illustration by Mauricio Anton

Eating bamboo? It’s all in the wrist.

When is a thumb not really a thumb? When it’s an elongated wrist bone of the giant panda that is used to grasp bamboo. Through its lengthy evolutionary history, the panda’s hand has never developed a truly opposable thumb. Instead, it evolved a thumb-like digit from a wrist bone, the radial sesamoid. This unique adaptation helps these bears subsist entirely on bamboo despite being bears (members of the order Carnivora, or meat-eaters).

In a new paper published today (June 30, 2022), scientists report the discovery of the earliest bamboo-eating ancestral panda to have this “thumb.” Surprisingly, it’s longer than its modern descendants. The research was conducted by the Natural History Museum of Los Angeles County’s Curator of Vertebrate Paleontology Xiaoming Wang and colleagues. 

While the celebrated false thumb in contemporary giant pandas (Ailuropoda melanoleuca) has been known for more than 100 years, it was not understood how this wrist bone evolved due to a near-total absence of fossil records. A fossil false thumb from an ancestral giant panda, Ailurarctos, dating back 6–7 million years ago was uncovered at the Shuitangba site in the City of Zhaotong, Yunnan Province in south China. It gives scientists a first look at the early use of this extra (sixth) digit–and the earliest evidence of a bamboo diet in ancestral pandas–helping us better understanding the evolution of this unique structure.

Chengdu panda eating bamboo. Credit: Reproduction of photo by permission from Sharon Fisher

“Deep in the bamboo forest, giant pandas traded an omnivorous diet of meat and berries to quietly consuming bamboos, a plant plentiful in the subtropical forest but of low nutrient value,” says NHM Vertebrate Paleontology Curator Dr. Xiaoming Wang. “Tightly holding bamboo stems in order to crush them into bite sizes is perhaps the most crucial adaptation to consuming a prodigious quantity of bamboo.” 

How to Walk and Chew Bamboo at the Same Time

This discovery could also help solve an enduring panda mystery: why are their false thumbs so seemingly underdeveloped? As an ancestor to modern pandas, Ailurarctos might be expected to have even less well-developed false“thumbs,” but the fossil Wang and his colleagues discovered revealed a longer false thumb with a straighter end than its modern descendants’ shorter, hooked digit. So why did pandas’ false thumbs stop growing to achieve a longer digit?

“Panda’s false thumb must walk and ‘chew’,” says Wang. “Such a dual function serves as the limit on how big this ‘thumb’ can become.”

Panda gripping vs walking (white bone is the false thumb). Credit: Courtesy of the Natural History Museum of L.A. County

Wang and his colleagues think that modern panda’s shorter false thumbs are an evolutionary compromise between the need to manipulate bamboo and the need to walk. The hooked tip of a modern panda’s second thumb lets them manipulate bamboo while letting them carry their impressive weight to the next bamboo meal. After all, the “thumb” is doing double duty as the radial sesamoid–a bone in the animal’s wrist.

“Five to six million years should be enough time for the panda to develop longer false thumbs, but it seems that the evolutionary pressure of needing to travel and bear its weight kept the ‘thumb’  short–strong enough to be useful without being big enough to get in the way,” says Denise Su, associate professor at the School of Human Evolution and Social Change and research scientist at the Institute of Human Origins at Arizona State University, and co-leader of the project that recovered the panda specimens.

“Evolving from a carnivorous ancestor and becoming a pure bamboo-feeder, pandas must overcome many obstacles,” Wang says. “An opposable ‘thumb’ from a wrist bone may be the most amazing development against these hurdles.”

Reference: “Earliest giant panda false thumb suggests conflicting demands for locomotion and feeding” by Xiaoming Wang, Denise F. Su, Nina G. Jablonski, Xueping Ji, Jay Kelley, Lawrence J. Flynn and Tao Deng, 30 June 2022, Scientific Reports.
DOI: 10.1038/s41598-022-13402-y

The authors of this article are affiliated with the Natural History Museum of Los Angeles County, Los Angeles, CA, USA; Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China; Arizona State University, Tempe, Arizona, USA; Pennsylvania State University, University Park, Pennsylvania, USA; Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China; Yunnan Institute of Cultural Relics and Archaeology, Kunming, Yunnan, China; Harvard University, Cambridge, Massachusetts, USA.

Funding was provided by the U.S.A. National Science Foundation, Yunnan Natural Science Foundation, National Natural Science Foundation of China, the Governments of Zhaotong and Zhaoyang, Institute of Vertebrate Paleontology and Paleoanthropology.



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Pandas evolved their most perplexing feature at least 6 million years ago

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But their ancestors, like most bears, ate a much wider diet that included meat, and it was thought that modern pandas’ exclusive diet evolved relatively recently. However, a new study finds that pandas’ particular passion for bamboo may have originated at least 6 million years ago — possibly due to the plant’s wide, year-round availability.

To survive solely on low-nutrient bamboo, modern pandas (Ailuropoda melanoleuca) have developed a peculiar sixth finger, a thumb of sorts that allows them to easily grasp bamboo stalks and strip the leaves.

“Tightly holding bamboo stems in order to crush them into bite sizes is perhaps the most crucial adaptation to consuming a prodigious quantity of bamboo,” said study author Xiaoming Wang, curator of vertebrate paleontology at the Natural History Museum of Los Angeles County, in a statement.

Wang and his team identified much earlier proof of pandas having an extra finger — and thus an all-bamboo diet — in the form of a fossilized digit dating back 6 to 7 million years. The fossil, unearthed in Yunnan Province in southwest China, belonged to a panda ancestor known as Ailurarctos.

The new research published Thursday in the journal Scientific Reports.

While the giant panda’s sixth digit is not as elegant or dexterous as human thumbs, the persistence of this “distinctive morphology” over millions of years suggested that it plays an essential function for survival, the study noted.

Evolutionary compromise

But what was particularly puzzling to the scientists involved in the study was that this fossilized structure was longer than those of modern giant pandas, which have a shorter, hooked sixth finger.

Wang and his colleagues think modern pandas’ shorter sixth digit is an evolutionary compromise between the need to manipulate bamboo and the need to walk and carry their hefty bodies.

“Five to six million years should be enough time for the panda to develop longer false thumbs, but it seems that the evolutionary pressure of needing to travel and bear its weight kept the ‘thumb’ short — strong enough to be useful without being big enough to get in the way,” said study coauthor Denise Su, an associate professor at the School of Human Evolution and Social Change and research scientist at the Institute of Human Origins at Arizona State University, in a statement.

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