Originating from forests nestled in mountain ranges throughout China, the iconic giant panda has long fascinated the world with its distinctive black and white fur.
But amid the sea of black and white fur, a rare sight occasionally emerges: a panda decorated in rich brown tones.
For years, the origins of these unconventional pandas have puzzled scientists and conservationists alike, with experts previously attributing their mutation to inbreeding or environmental factors.
Now, a groundbreaking study conducted by researchers in Beijing, China, has shed light on this fascinating phenomenon, uncovering the genetic underpinnings behind the existence of brown pandas and dispelling the idea that inbreeding is the cause.
After examining the genetics of pandas in the wild and in captivity, scientists at the Institute of Zoology of the Chinese Academy of Sciences in Beijing have suggested that pandas with brown and white coats are the result of natural variation.
Originating from forests nestled in mountain ranges throughout China, the iconic giant panda has long fascinated the world with its distinctive black and white fur (stock image)
For years, the origin of rare pandas with brown-and-white coats has puzzled scientists and conservationists alike – but scientists have now shed light on this fascinating phenomenon
Senior author Dr. Fuwen Wei, professor of wildlife ecology and conservation biology at the institute, has said that gaining a better understanding of the mutation could aid efforts to breed brown-and-white pandas in captivity.
The first brown panda known to science was a female named Dan Dan, a sick bear found in 1985 by a local forest ranger in Foping County in the Qinling Mountains of Shaanxi Province.
The panda was kept in captivity at the Xi’an Zoo until her death in 2000 – but shockingly, there have been only eleven sightings of brown pandas since her discovery almost four decades ago, according to CNN.
Each sighting has been documented through official news reports and/or through personal accounts shared with the authors of the latest study appearing in the journal PNAS on March 4.
Led by a team of geneticists and conservationists, the research delved into the intricate DNA of both brown and black and white pandas, including analyzing hair samples from bears in different regions of China.
The researchers studied Qizai, a male brown panda who was rescued as a cub from the Foping National Nature Reserve in Hanzhong in 2009. He is currently the only brown panda in captivity.
Compared under a microscope to hair samples from three black and white pandas, Qizai’s brownish fur had fewer and smaller melanosomes, small structures found in cells responsible for skin and hair pigment in mammals.
While piecing together his family tree, researchers discovered that Qizai’s mother and father were black and white pandas, while Qizai’s son, born in captivity in 2020, was also born with a black and white coat.
The researchers studied Qizai (pictured), a male brown panda who was rescued as a cub from the Foping National Nature Reserve in Hanzhong in 2009
Researchers were able to show that Qizai’s parents and son each had one copy of the recessive trait of a gene known as Bace2, while Qizai had two copies.
Findings have also shown that the first brown bear discovered, Dan Dan, had the same recessive trait
Dr. Fuwen Wei has said that gaining a better understanding of the mutation could aid efforts to breed brown-and-white pandas such as Qizai (pictured, left) in captivity.
The scientists studied genetic information – such as feces and blood samples – from Qizai’s relatives and compared it with that of 12 black-and-white pandas from the Qinling Mountains and 17 black-and-white pandas from other regions in China.
Although none of Qizai’s immediate relatives had brown fur, the researchers were able to show that his parents and son each had one copy of the recessive trait of a gene known as Bace2, while Qizai had two copies.
An analysis of a tissue sample preserved in ethanol for more than twenty years also allowed scientists to study Dan Dan’s genome – and the findings have shown that the first brown bear discovered had the same recessive trait.
However, it is not clear what causes the genetic mutation. Dr. Wei suggests that this could be related to the specific environment of the Qinling Mountains, which has a different climate than Sichuan.
He added: ‘It is more likely to be a result of natural variation than inbreeding. Our kinship analysis shows that Qizai’s parents are not closely related.’
In 2022, Qizai, who is now 15 years old, mated naturally for the first time with a partner at a Chinese breeding center.