The giant panda holds potential for further evolution (8/22/2007)

Giant Panda still possesses high genetic diversity and evolutionary potential

Employing microsatellite and mitochondrial control region (CR) sequences as genetic markers, CAS researchers have obtained some key information about the giant panda (Ailuropoda melanoleuca) and depicted its recent evolution history. They discovered that the lovely species still possesses high genetic diversity and evolution potentials, putting an end to the hypothesis suggesting the giant panda is facing an "evolutionary dead-end". The research is reported in the volume 24:1801-1810 of Molecular Biology and Evolution by a team of scientists from China and the UK, led by Prof. WEI Fuwen of the CAS Institute of Zoology and Prof. Michael W. Bruford of Cardiff University.

The giant panda is currently threatened by habitat loss, fragmentation and human persecution. Its dietary specialization, habitat isolation and reproductive constraints have led to a perception that this is a species at an 'evolutionary dead-end', destined for deterministic extinction in the modern world. In order to better understand the evolutionary history of giant panda, a research group led by Prof. Fuwen Wei, collaborated by experts from Sichuan Forest administration, Cardiff University, UK and China West Normal University, they examined the genetic variation of mitochondrial DNA control region and nuclear DNA microsatellite, population structure, gene flow and population demography, with a plenty of genetic samples from its five extant mountain populations.

Surprisingly, they found that extant populations display average to high levels of CR and microsatellite diversity compared with other bear species. Genetic differentiation among populations was significant in most cases but was markedly higher between Qinling and the other mountain ranges, suggesting, minimally, that the Qinling population should comprise a separate management unit for conservation purposes. Recent demographic inference using microsatellite markers demonstrated a clear genetic signature for population decline starting several thousands years ago or even further back in the past, and being accelerated and enhanced by the expansion of human populations. Importantly, these data suggest that the panda is not a species at an evolutionary 'dead-end', but in common with other large carnivores, has suffered demographically at the hands of human pressure. Therefore, their finding revised the long-term public comprehension for the giant panda's future; they are not the remaining species close to its evolutionary dead-end, but the flourishing animal with evolutionary potential. The decline of giant panda populations was completely attributed to some external factors but themselves. Human being should take the responsibilities for their endangered situation!

Recently wild giant panda census show that companied with the improved habitats, the wild giant panda populations has recovered gradually. It ascribed to a series of effective conservation measures taken by the Chinese government, such as Giant panda Habitat Conservation Project, Natural Forest Conservation Project, Grain-to-Green Project, giant panda nature reserve network establishment and poaching forbidden. Obviously, these endeavors are gaining huge ecological benefits now. On the other hand, it also reflects the flourishing potential of current giant panda population, by no means close to the evolutionary dead-end!

We are confident that under the long-term and effective conservation endeavor, giant panda may have a significantly better chance of long-term viability; the beautiful species will own a brighter future!

The researchers include Baowei Zhang, Ming Li, Lifeng Zhu, Shanning Zhang and Fuwen Wei of the Institute of Zoology (IOZ), Chinese Academy of Sciences in Beijing, People's Republic of China; Zejun Zhang and Jinchu Hu of China West Normal University in Sichuan, People's Republic of China; Benoit Goossens and Michael Bruford of Cardiff University in Cardiff, United Kingdom.

Zhang et al.: "Genetic viability and population history of the giant panda, putting an end to the evolutionary dead-end?" Published in Molecular Biology and Evolution, 24(8):1801-1810, 2007, http://mbe.oxfordjournals.org/

Note: This story has been adapted from a news release issued by the Chinese Academy of Sciences

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