A recent study published in the Journal of Vertebrate Paleontology reveals the origins of the global panda species and the reasons for its extinction.
When researchers examined teeth that had been preserved for about 40 years, they discovered that this fossil belonged to an ancient panda species never before seen in Europe. The newly identified species, a close relative of the modern giant panda, roamed the continent around 6 million years ago and may represent the last of the European panda lineage.
The last giant pandas of Europe could not chew bamboo.
The teeth—a single upper canine and an upper molar—were originally excavated in the late 1970s from a site in northwestern Bulgaria, but they were eventually stored at the National Museum of Natural History in Sofia. Typically, researchers overlook teeth, so they were “forgotten” for over 40 years. However, when museum staff recently stumbled upon the unusual teeth, they decided to investigate further.
After analyzing the teeth, the researchers realized they belonged to an ancient European panda, but the fossil did not resemble any previously identified panda teeth in Europe. Most European panda species had smaller teeth than the modern giant panda (Ailuropoda melanoleuca), indicating that they could have been much smaller than their modern relatives.
However, the new species, named Agriarctos nikolovi, had much larger teeth than typical European pandas, suggesting it could have been similar in size to today’s giant pandas. The teeth also date much more recently than other European panda fossils, some of which are over 10 million years old, indicating that A. nikolovi may have been the last panda species to inhabit the continent.
Co-author Nikolai Spassov, a paleontologist at the National Museum of Natural History in Bulgaria, stated: “This discovery shows how little we know about ancient nature. The fact that a new species has emerged from a specimen found in the 1970s demonstrates that historical discoveries in paleontology can lead to surprising results, even to this day.”
Despite the size similarities between A. nikolovi and living giant pandas, the newly described species is not a direct ancestor of the modern genus, but rather a distant relative. However, this new species may have lived in a very different habitat compared to today’s pandas.
The fossilized teeth were initially found in coal mines, which somewhat stained the teeth of this panda species black. The coal composition in the area suggests it was once a swampy forest. This means that A. nikolovi may have had a much more varied diet than modern pandas, consuming a wider range of soft vegetation rather than just one type, such as bamboo, which modern pandas typically eat.
Interestingly, the digestive system of giant pandas appears capable of processing meat, similar to other bear species, yet they adhere to a strict herbivorous diet.
Previous research has suggested that giant pandas shifted to a bamboo diet due to competition from other bear species. Researchers believe that A. nikolovi may have also faced similar evolutionary pressures to adopt a vegetarian diet, as its teeth were much weaker than those of modern pandas, meaning they may not have been able to chew bamboo, let alone something hard like animal bones.
The study authors also suspect that A. nikolovi may have ultimately gone extinct due to climate change affecting their habitat and diet.
Spassov remarked: “It is likely that climate change at the end of the Miocene (23 million to 5.3 million years ago) in southern Europe negatively impacted the survival of the last European panda species.” Researchers suggest that A. nikolovi may have been particularly vulnerable to an event that occurred about 6 million years ago: the Messinian salinity crisis, when the Mediterranean Sea nearly dried up completely, causing severe consequences for terrestrial ecosystems. The swampy forests of the ancient panda may have become much drier and warmer, making it difficult for plants to grow and potentially leading to starvation for the pandas.
The research team remains uncertain about how A. nikolovi and other extinct European panda species are related to the giant panda and ancient Asian pandas.
It is still unclear whether pandas originated in Asia and migrated to Europe or vice versa. However, researchers suspect that pandas originated in Europe, as fossil evidence indicates that the oldest members of this bear group were found in Europe.
