Pandas are NOT all black and white - and now scientists know why some are different colours

Hailing from forests nestled within mountain ranges across China, the iconic giant panda has long captivated the world with its distinctive black and white coat. 

Yet, amidst the sea of monochrome fur, a rare sight occasionally emerges - a panda adorned in rich shades of brown.

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 captivating phenomenon, uncovering the genetic underpinnings behind the existence of brown pandas and dispelling the notion of inbreeding as the cause.

After examining the genetics of pandas in the wild and in captivity, scientists at the Chinese Academy of Sciences' Institute of Zoology in Beijing have suggested that pandas with brown-and-white coats are the result of natural variation.

Hailing from forests nestled within mountain ranges across China , the iconic giant panda has long captivated the world with its distinctive black and white coat (stock image)

For years, the origins of rare pandas with brown-and-white coats have puzzled scientists and conservationists alike - but scientists have now shed light on this captivating phenomenon

Senior author Dr. Fuwen Wei, a professor of wildlife ecology and conservation biology at the institute, has said that gaining a better understanding of the mutation could help inform efforts to breed brown-and-white pandas in captivity.

The first brown panda known to science was a female named Dan Dan, an ailing bear found by a local ranger in Foping County in Shaanxi province's Qinling Mountains in 1985. 

The panda was held in captivity at Xi'an Zoo until her death in 2000 - but, shockingly, since her discovery nearly four decades ago, there have only been 11 sightings of brown pandas, according to CNN. 

Each sighting has either been have been documented through official news reports and or through personal accounts shared with the authors of the latest study that appeared in the journal PNAS on March 4. 

Led by a team of geneticists and conservationists, the study delved into the intricate DNA of both brown and black-and-white pandas, including analysing hair samples from bears across various regions of China. 

The researchers studied Qizai, a male brown panda rescued as a cub in 2009 from Foping National Nature Reserve in Hanzhong. He is currently the only brown panda in captivity. 

When compared under a microscope with hair samples from three black-and-white pandas, Qizai's brownish fur had fewer and smaller melanosomes, tiny structures found in cells that are responsible for skin and hair pigment in mammals. 

Piecing together his family tree, researchers found 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 rescued as a cub in 2009 from Foping National Nature Reserve in Hanzhong

Researchers were able to show that Qizai's parents and son all had one copy of the recessive trait on a gene known as Bace2, while Qizai had two copies 

Findings have also shown that the first discovered brown bear, Dan Dan, had the same recessive trait

Dr. Fuwen Wei has said that gaining a better understanding of the mutation could help inform efforts to breed brown-and-white pandas, such as Qizai (pictured, left) in captivity

The scientists studied genetic information - such as scat and blood samples - from Qizai's family members 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.

While none of Qizai's immediate family members had brown fur, the researchers were able to show that his parents and son all had one copy of the recessive trait on a gene known as Bace2, while Qizai had two copies. 

Thanks to an analysis of a tissue sample stored for more than two decades in ethanol, scientists also were able to study the genome of Dan Dan - and findings have shown that the first discovered brown bear had the same recessive trait.

However, it is not clear what causes the genetic mutation, with Dr. Wei suggesting it could be linked 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 rather than inbreeding. Our kinship analysis indicates that Qizai's parents are not closely related.'

In 2022, Qizai, who is now 15-years-old, mated naturally with a partner for the first time at a Chinese breeding centre.