Though only 1,500 exist in the wild and despite the fact they've been on the endangered species list since the early 1990s, giant pandas are more naturally protected against extinction than previously predicted, according to a study published in Bio Med Central on Tuesday.
All wild pandas are dispersed among six mountain ranges in south China, according to the study. Since those groups don't interact or breed with each other, scientists worried that a lack of genetic diversity would ultimately doom the species. If, for example, the environment dramatically changed against pandas, the prevailing thought was that the species wouldn't have enough genetic options to adapt.
"The assumption is that a decrease in genetic variation and a lack of exchange between isolated populations increase the likelihood of extinction by reducing the population's ability to adapt to changing environments," study co-authors Ying Zhu, Qiu-Hong Wan, Bin Yu, Yun-Fa Ge and Sheng-Guo Fang wrote.
To test their suspicions, researchers analyzed a section of genome called the major histocompatibility complex (MHC), which is most directly related to environmental adaptation and the immune system. Comparing panda DNA to the brown bear (not endangered), researchers found less genetic diversity in pandas. Comparing their DNA to other endangered species such as Bengal tigers and Namibia cheetahs, however, revealed greater levels of genetic diversity.
The genetic diversity varied between the six groups, so much so that researchers felt one group could have been considered a separate subspecies. But that feeling wasn't strong enough; ultimately, researchers recommended the group known as QLI, whose skulls were smaller and molars larger, be "monitored and managed separately" from the other groups.
The group known as XXL had the highest genetic diversity and the smallest number of pandas (32). Researchers believe this group had "risen from an ancestral population with higher levels of genetic diversity."
Knowing that pandas have more natural genetic options and which subgroups have the most will be important for conservationists and protectors of the panda population. Researchers in this study recommend that breeders generally use pandas with the most diverse genetics.
"If you need to capture 10 pandas for a captive breeding program, then you choose those 10 to encompass the most diversity," biologist Paul Hohenlohe told Live Science. "You can do that by getting them from multiple populations, or one population that has the most diversity."
