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The Chinese pangolin (Manis pentadactyla) is distributed in Nepal, Sikkim, Myanmar, northern Vietnam, and the area south of the Yangtze River in my country. Due to habitat loss, overexploitation, climate change and other factors, the population is in a critically endangered state and is listed in the national first-class key protected wild animal list. It is a flagship species for biodiversity conservation in my country. At present, conservation genetics research on this species is limited to populations in Yunnan, Guangdong, Taiwan and other places, which limits the scientific protection and management of the Chinese pangolin.

In order to solve the above scientific problems, the team led by Academician Wei Fuwen, director of the Jiangxi Provincial Key Laboratory of Conservation Biology at Jiangxi Agricultural University, collected 94 samples from 11 provinces or regions covering the main distribution areas of Chinese pangolins for genome resequencing analysis, and found that Chinese pangolins can be divided into three main genetic lineages , namely MPA, MPB and MPC. Among them, MPA is distributed in the southern Qinghai-Tibet Plateau, MPB is distributed in provinces south of the Yangtze River in China (including Hainan and Taiwan), and MPC is distributed in the northeast of Indochina (including Vietnam and Laos).

Combining the geographical distribution information of the samples and the simulation results of the distribution of suitable habitats for the species, it is inferred that the geographical boundary between MPA and MPB is the Hengduan Mountains, and the geographical boundary between MPB and MPC is the subtropical and tropical boundary. Further analysis found that the MPB lineage can be further divided into two genetic populations, namely MPB1 distributed in the Yunnan Plateau and MPB2 distributed in the rest of my country.

Fig. 1 Sampling information and population genetic structure of Chinese pangolin

Analysis of the history of Chinese pangolin populations found that the differentiation between populations was mainly affected by the climate fluctuations of the Pleistocene . The main manifestation was that the common ancestor of Chinese pangolins experienced a population bottleneck and differentiation about 200,000 years ago, which corresponds to the penultimate ice age of the Pleistocene. After that, the population declined and differentiated during the last glacial maximum 16,000 years ago, and the area of ​​suitable habitat also decreased significantly.

On the other hand, the research team comprehensively evaluated the genetic diversity, evolutionary history, inbreeding level and evolutionary potential of the four populations, and put forward corresponding protection and management recommendations . The MPA population has the lowest genetic diversity, the highest level of long-term inbreeding and the highest genetic load, indicating that the population is likely to be blocked by the high mountains of the Hengduan Mountains, resulting in a lack of gene exchange within the population, forming an isolated population with a high risk of extinction; while the introduction of new individuals from other populations does not lead to an increase in harmful mutation sites in the MPA population, so it is recommended to introduce new individuals from other areas to improve the evolutionary potential of the MPA population.

The MPB1 population has the highest genetic diversity, the largest effective population size, the smallest population decline and the lowest inbreeding level, and is an important germplasm resource of the Chinese pangolin. The MPB2 and MPC populations have the smallest effective population size and a high level of recent inbreeding; and their effective population size has dropped sharply in the past 50 years, which is related to the large increase in the population in the region, indicating that human activities have had a profound negative impact on them. Therefore, for the MPB2 and MPC populations, the current priority is to strengthen in situ protection and restore the population.

It is worth mentioning that there has been no significant increase in harmful mutations in the Chinese pangolin population, indicating that if effective protection and management measures are taken, there is still great hope for the recovery of the species population. It is not too late to protect the Chinese pangolin!

Figure 2 Evolutionary history of Chinese pangolin populations

This study systematically clarified the conservation genetic units, population history and evolutionary potential of the Chinese pangolin, and put forward targeted conservation and management recommendations. The research results provide important scientific guidance for the conservation and management of the Chinese pangolin, and serve the national needs for the protection of endangered flagship species such as the Chinese pangolin.

The research results were recently published online in Science China Life Sciences under the title “ Conservation genomics of the critically endangered Chinese pangolin ”.