大熊猫是全球最濒危的哺乳动物之一。据资料记载,从1938年到1988年近50年时间里,由于受栖息地丧失、大规模竹子开花死亡以及猎捕等生态和人为事件的影响,野生大熊猫种群数量急剧下降,在当时引起全世界对大熊猫命运的关注,并认为该种群数量下降将对其种群生存力造成严重影响。
中国科学院动物研究所魏辅文研究员领导的动物生态与保护遗传学研究组以1988年《野生动物保护法》颁布实施和1988年最后一次竹子开花为时间节点,比较分析了1988年前后大熊猫历史和现生种群线粒体DNA和微卫星变异,发现其遗传多样性和有效种群大小在历史和现生种群间没有显著差异,说明现生大熊猫种群仍维持较高的遗传多样性及进化潜力。但是,通过模拟未来200年大熊猫遗传多样性变化趋势时显示,如果其栖息地破碎化现状及隔离种群间有限的基因流得不到有效的改善,其遗传多样性将在未来缓慢丧失,会对大熊猫种群生存力产生不利影响。他们建议,进一步加大大熊猫栖息地恢复力度并增加栖息地连接度,以促进隔离种群间的基因流,维持其遗传多样性及进化潜力。研究结果在Ecology上发表。
该项目得到国家自然科学基金委员会重点项目(31230011)和中国科学院知识创新工程项目(KSCX2-EW-Z-4)的资助。(生物谷 Bioon.com)
生物谷推荐的英文摘要
Ecology doi.org/10.1890/12-1451.1
Genetic consequences of historical anthropogenic and ecological events on giant pandas
Lifeng Zhu 1, Yibo Hu 2, Dunwu Qi 3, Hua Wu 4, Xiangjiang Zhan 5, Zhejun Zhang 6, Michael Bruford 7, Jinliang Wang 8, Xuyu Yang 9, Xiaodong Gu 10, Lei Zhang 11, Baowei Zhang 12, Shanning Zhang 13, and Fuwen Wei 14,*
The giant panda (Ailuropoda melanoleuca) was taken to the brink of extinction in the 1980s through a combination of deforestation, large-scale loss of bamboo in the core of its range, poaching, and zoo collection, causing over 1,000 deaths from the 1950s. It was thought that the drastic population decline was likely to impose a severe impact on population viability. Here, based on temporal genotyping of individuals we show that this rapid decline did not significantly reduce the overall effective population size and genetic variation of this species, or of the two focal populations (Minshan and Qionglai) that declined the most. These results are contrary to previously assumptions, probably because the population decline has not produced the expected negative impact because of the short time scale involved (at most 10 generations), or because previous surveys underestimated the population size at the time of decline. However, if present-day habitat fragmentation and limited migration of giant pandas remains, we predict a loss of genetic diversity across the giant pandas' range in the near future. Thus, our findings highlight the substantial resilience of this species when facing demographic and environmental stochasticity, but key conservation strategies, such as enhancing habitat connectivity and habitat restoration should be immediately implemented to retain the extant genetic variation and maintain long-term evolutionary potential of this endangered species.