中国兽类多样性监测与研究网络建设:十年回顾与展望

兽类物种多样性高,分布广泛,与人类关系密切,对维持生态系统稳定平衡具有不可替代的作用。我国是世界上生态系统类型和兽类多样性最丰富的国家之一,但多数生态系统的兽类物种资源情况仍未完全掌握,许多区域缺乏调查记录或长期监测资料。面对全球生态环境的急剧变化,我国兽类动物资源保护面临严峻挑战。中国兽类多样性监测与研究网络(以下简称兽类网)于2011年启动建设,结合全球生物多样性保护背景下的国家重大需求,以陆生兽类及其栖息地为研究对象,先后建立了55个监测样区,逐渐形成覆盖全国的监测网络,发表有关论著180余篇(部),其中红外相机工作日累计超156万天,获得图像775余万张;同时,推动建立了我国兽类多样性监测标准化技术体系和公共数据服务平台,对兽类群落组成、种群动态和行为变化以及关键驱动因子开展长期监测研究,为我国重要兽类资源保护、有害生物管控提供先进技术和科学数据支撑。本文回顾了兽类网的发展历程,系统梳理了在监测技术方法、编目发现、行为生理、种群、种间关系、群落和保护管理方面的监测与研究进展。未来需加强技术和学科交叉,聚焦多尺度、多维度、多营养级的综合研究应用,为全面、深刻地理解生物多样性维持机制,应对生物多样性丧失的全球危机做好科技支撑与服务。

Conservation metagenomics: a new branch of conservation biology

Multifaceted approaches are required to monitor wildlife populations and improve conservation efforts. In the last decade,increasing evidence suggests that metagenomic analysis offers valuable perspectives and tools for identifying microbial communities and functions. It has become clear that gut microbiome plays a critical role in health, nutrition, and physiology of wildlife, including numerous endangered animals in the wild and in captivity. In this review, we first introduce the human microbiome and metagenomics, highlighting the importance of microbiome for host fitness. Then, for the first time, we propose the concept of conservation metagenomics, an emerging subdiscipline of conservation biology, which aims to understand the roles of the microbiota in evolution and conservation of endangered animals. We define what conservation metagenomics is along with current approaches, main scientific issues and significant implications in the study of host evolution, physiology,nutrition, ecology and conservation. We also discuss future research directions of conservation metagenomics. Although there is still a long way to go, conservation metagenomics has already shown a significant potential for improving the conservation and management of wildlife.

Seasonal and reproductive variation in chemical constituents of scent signals in wild giant pandas

Seasonally reproducing animals show many behavioral and physiological changes during the mating period, including increased signaling for intrasexual competition and mate attraction. We collected 102 anogenital gland secretions(AGS) from marking trees in Foping Nature Reserve, and used gas chromatography mass spectrometry to analyze these chemical composition. Of these marks, all but one were from males, confirmed with DNA analysis. We found that several chemical constituents, especially volatile compounds, were present only during the mating season and that the relative abundance of many compounds changed as a function of breeding season, whereas nonvolatile compounds were lower in the mating season. This seasonal variation in chemical composition of AGS most likely plays an important role in governing giant panda reproduction, including mate location, attraction, and male-male competition. The chemical properties of many of these putative chemosignals—such as volatility and longevity—are suggestive of these roles, and undoubtedly contribute to successful reproduction for this species with a characteristically sophisticated chemical communication system. We also found a number of important differences between the chemical constituents of AGS from wild pandas and those found in previous studies with captive pandas, suggesting that inappropriate chemosignal composition may contribute to poor reproductive success in captive breeding programs.

Diet drives convergent evolution of gut microbiomes in bamboo-eating species

Gut microbiota plays a critical role in host physiology and health.The coevolution between the host and its gut microbes facilitates animal adaptation to its specific ecological niche.Multiple factors such as host diet and phylogeny modulate the structure and function of gut microbiota.However,the relative contribution of each factor in shaping the structure of gut microbiota remains unclear.The giant(Ailuropoda melanoleuca)and red(Ailurus styani)pandas belong to different families of order Carnivora.They have evolved as obligate bamboo-feeders and can be used as a model system for studying the gut microbiome convergent evolution.Here,we compare the structure and function of gut microbiota of the two pandas with their carnivorous relatives using 16S rRNA and metagenome sequencing.We found that both panda species share more similarities in their gut microbiota structure with each other than each species shares with its carnivorous relatives.This indicates that the specialized herbivorous diet rather than host phylogeny is the dominant driver of gut microbiome convergence within Arctoidea.Metagenomic analysis revealed that the symbiotic gut microbiota of both pandas possesses a high level of starch and sucrose metabolism and vitamin B12 biosynthesis.These findings suggest a diet-driven convergence of gut microbiomes and provide new insight into host-microbiota coevolution of these endangered species.

Ecological scale and seasonal heterogeneity in the spatial behaviors of giant pandas

We report on the first study to track the spatial behaviors of wild giant pandas(Ailuropoda melanoleuca)using high-resolution global positioning system(GPS)telemetry.Between 2008 and 2009,4 pandas(2 male and 2 fe-male)were tracked in Foping Reserve,China for an average of 305 days(±54.8 SE).Panda home ranges were larger than those of previous very high frequency tracking studies,with a bimodal distribution of space-use and distinct winter and summer centers of activity.Home range sizes were larger in winter than in summer,although there was considerable individual variability.All tracked pandas exhibited individualistic,unoriented and multi-phasic movement paths,with a high level of tortuosity within seasonal core habitats and directed,linear,large-scale movements between habitats.Pandas moved from low elevation winter habitats to high elevation(>2000 m)summer habitats in May,when temperatures averaged 17.5°C(±0.3 SE),and these large-scale movements took<1 month to complete.The peak in panda mean elevation occurred in Jul,after which they began slow,large-scale movements back to winter habitats that were completed in Nov.An adult female panda made 2 long-distance movements during the mating season.Pandas remain close to rivers and streams during winter,possi-bly reflecting the elevated water requirements to digest their high-fiber food.Panda movement path tortuosity and first-passage-time as a function of spatial scale indicated a mean peak in habitat search effort and patch use of approximately 700 m.Despite a high degree of spatial overlap between panda home ranges,particularly in winter,we detected neither avoidance nor attraction behavior between conspecifics.

Conservation genetics and genomics of threatened vertebrates in China

Conservation genetics and genomics are two independent disciplines that focus on using new techniques in genetics and genomics to solve problems in conservation biology. During the past two decades,conservation genetics and genomics have experienced rapid progress. Here, we summarize the research advances in the conservation genetics and genomics of threatened vertebrates(e.g., carnivorans, primates, ungulates, cetaceans, avians, amphibians and reptiles) in China. First, we introduce the concepts of conservation genetics and genomics and their development. Second, we review the recent advances in conservation genetics research, including noninvasive genetics and landscape genetics. Third, we summarize the progress in conservation genomics research, which mainly focuses on resolving genetic problems relevant to conservation such as genetic diversity, genetic structure, demographic history, and genomic evolution and adaptation. Finally, we discuss the future directions of conservation genetics and genomics.

Noninvasive genetics provides insights into the population size and genetic diversity of an Amur tiger population in China

Understanding population size and genetic diversity is critical for effective conservation of endangered species.The Amur tiger(Panthera tigris altaica)is the largest felid and a flagship species for wildlife conservation.Due to habitat loss and human activities,available habitat and population size are continuously shrinking.However,little is known about the true population size and genetic diversity of wild tiger populations in China.In this study,we collected 55 fecal samples and 1 hair sample to investigate the population size and genetic diversity of wild Amur tigers in Hunchun National Nature Reserve,Jilin Province,China.From the samples,we determined that 23 fecal samples and 1 hair sample were from 7 Amur tigers:2 males,4 females and 1 individual of unknown sex.Interestingly,2 fecal samples that were presumed to be from tigers were from Amur leopards,highlighting the significant advantages of noninvasive genetics over traditional methods in studying rare and elusive animals.Analyses from this sample suggested that the genetic diversity of wild Amur tigers is much lower than that of Bengal tigers,consistent with previous findings.Furthermore,the genetic diversity of this Hunchun population in China was lower than that of the adjoining subpopulation in southwest Primorye Russia,likely due to sampling bias.Considering the small population size and relatively low genetic diversity,it is urgent to protect this endangered local subpopulation in China.

Distinctive diet-tissue isotopic discrimination factors derived from the exclusive bamboo-eating giant panda

Stable isotope analysis is very useful in animal ecology,especially in diet reconstruction and trophic studies.Differences in isotope ratios between consumers and their diet,termed discrimination factors,are essential for studies of stable isotope ecology and are species-specific and tissue-specific.Given the specialized bamboo diet and clear foraging behavior,here,we calculated discrimination factors for carbon and nitrogen isotopes from diet to tissues(tooth enamel,hair keratin and bone collagen)for the giant panda(Ailuropoda melanoleuca),a species derived from meat-eating ancestors.Our results showed that carbon discrimination factor obtained from giant panda tooth enamel(ε^(13)C_(diet-enamel)=10.0‰)and nitrogen discrimination factors from hair keratin(Δ^(15)N_(diet-hair)=2.2‰)and bone collagen(Δ^(15)N_(diet-collagen)=2.3‰)were lower,and carbon discrimination factors from hair ker­atin(Δ^(13)C_(diet-hair)=5.0‰)and bone collagen(Δ13Cdiet-collagen=6.1‰)were higher than those of other mammalian carnivores,omnivores and herbivores.Such distinctive values are likely the result of a low-nutrient and special­ized bamboo diet,carnivore-like digestive system and exceptionally low metabolism in giant pandas.