矮岩羊行为生态的初步研究

2006年8月,在四川巴塘县竹巴笼自然保护区对矮岩羊的行为生态进行了研究。共发现矮岩羊7个集群33只,集群平均大小为4.71±1.60只;矮岩羊在夏季9:00~10:00内主要用于卧息,占该段活动时间的76.72%;因子分析显示:矮岩羊对生境的利用具有选择性,影响矮岩羊生境选择行为的主要因子为草因子、灌木因子、坡度和活动基底特征。     

论生物多样性发展史研究的现状及意义*

论生物多样性发展史研究的现状及意义李中明（中国科学院植物研究所,北京１０００４４）由于生物多样性对人类生存的重要性及目前所遭受的严重威胁,人们对生物多样性保护的研究正在日益受到重视,并从早期的对物种多样性研究扩展至生态系统多样性、遗传多样性、景观多样...     

矮岩羊

报道了矮岩羊种的分类、种群的分布、数量、种群行为生态等方面的研究状况以及今后的研究方向。     

岩羊和矮岩羊头骨形态特征比较

本文报道了岩羊和矮岩羊的头骨形态学资料,涉及头骨特征描述和一些形态学指标测定,被测定的指标主要有上颊齿列基长、眼窝长、乳突间距、眶间距、颧宽、枕颅高、枕髁宽、脑颅最大宽、眶下孔距、上颌臼齿外宽、角基最窄、最小角尖距、角尖距、最大角间距、角基周长、角基长径、角基短径、角外侧长,应用判别分析和单变量分析对岩羊和矮岩羊头骨的测量值进行统计与分析,以探讨这两个种头骨之间的形态差异。结果表明：（1）岩羊和矮岩羊头骨在形态上十分相似,但矮岩羊的头骨细长,脑颅狭窄,角直且朝上翘,角内侧具一明显角棱,亦较直,角基部狭窄,老年个体角基部愈合;岩羊的脑颅宽大,角粗大而长,向两侧分开,弯曲度较大,内侧角棱弯曲呈长S型,角尖朝向后方,角基部较宽,不愈合在一起。（2）岩羊和矮岩羊头骨的18项形态测量指标中乳突间距、眶间距、颧宽、脑颅最大宽、上颌臼齿外宽、角基周长、角基长径差异极显著（P〈0.01）,枕颅高、枕髁宽、眶下孔距、角尖距、最大角间距、角基短径、角外侧长差异显著（P〈0.05）;典型判别的正确率：岩羊为100%,矮岩羊为83.3%,交互验证法检验的结果,判别正确率：岩羊100%,矮岩羊为83.3%。这两个判别函数可以从角上区别岩羊和矮岩羊。     

四川省竹巴笼自然保护区矮岩羊的集群特征

2007 年7 ～12 月和2008 年4 ～6 月,采用样线法和定点观察法,在四川省竹巴笼自然保护区对矮岩羊集群行为进行了观察。2007 年观察到34 群共217 只矮岩羊,集群平均为6. 4 ± 4.9 只;2008 年观察到16 群共135只,集群平均为8.4 ± 7.7 只。集群分为雄性群(2007 年:8.8% ;2008 年:6.3% )、雌性群(2007 年:2. 9% ;2008 年:0)、混合群(2007 年:70.6% ;2008 年:81.2% )、母仔群(2007 年:8.8% ;2008 年:12. 5% )和孤羊(2007 年:8.8% ;2008 年:0)5 种类型。在不同季节,5 种集群类型比例都有所变化,差异显著(P <0.01)。集群大小间和集群类型间也有显著或极显著差异,其中2 ～ 10 只的集群在2007 年占73.5%,在2008 年占75.0% ,呈集小群特征。年龄组结构中,成体、亚成体和幼体个体数比为100∶ 26.4∶ 28. 6 (2007 年)和100∶24.7∶ 20. 4 (2008 年)。雌雄性比2007 年为100∶ 55.7,2008 年为100∶ 56.6,年间差异不显著(P > .05)。受集群收益、生物学特征、繁殖周期、资源竞争、生境地形地貌、捕食风险和人类活动等主要因素的影响,矮岩羊在集群类型、集群大小、年龄结构和性比上显示了其生存策略。     

春季岩羊种群生态学特征的初步研究

本文通过对贺兰山春季岩羊的研究得出,贺兰山的岩羊为晨昏性活动动物,两个活动高峰分别在５００～９００和１７００～２０００。在春季,岩羊群主要以小群为主,且主要是混合群,平均群大小为５．６头;整个贺兰山的岩羊密度为３．６头／ｋｍ２;岩羊的雌雄性比为１１．３６,并指出目前偷猎仍然影响着种群的性比;雄性岩羊的自然死亡年龄在６．５～１０．５岁,其中以９．５岁是其自然死亡的高峰时期。     

基于DNA条形码和微卫星标记分析矮岩羊的进化地位

岩羊Pseudois nayaur是目前岩羊属Pseudois中承认的唯一物种,主要分布在青藏高原及其周边山脉地区,是该地区代表性的大型有蹄类动物。岩羊种内存在矮岩羊这一个形态特异的种群,其分类地位一直处在争议当中。本次研究从岩羊分布区域内搜集到26个岩羊样品,其中包括5个矮岩羊样品,选取了COⅠ基因DNA条形码标准区域和8个微卫星标记位点探讨了矮岩羊与岩羊不同地理种群的系统进化关系,同时分析了矮岩羊的进化地位。结果表明矮岩羊和岩羊间目前处于基因交流半隔离状态,不应该被分为2个不同的物种或者亚种,而矮岩羊应该被作为岩羊四川亚种P.n.szechuanensis中一个形态变异的特殊分类群。另外,结合生境选择和生态观察的结果推测矮岩羊目前可能已经处于单独进化的早期阶段。     

冬春季矮岩羊集群特征比较

2007年10月至12月、2008年11月中旬至2009年1月中旬和2009年3月至5月,采用样线法对四川竹巴笼自然保护区矮岩羊冬春季的集群特征进行了研究,春季共观察到73群451只矮岩羊,冬季共观察到170群1036只矮岩羊。发现春季平均群大小为6.18±5.186,最大群34只;冬季平均集群大小为6.65±4.564,最大群24只;春冬两季矮岩羊集群大小季节性变化不显著(P0.05)。在观察到的矮岩羊中,冬春两季矮岩羊集群都以混合群为主,分别占57.20%和45.20%;与春季相比,冬季混合群和独羊出现频率增高,而春季雌性群和母仔群增多;2-8只的集群冬季109群,春季56群,分别占总群数的64.12%和76.71%;9只以上的集群冬季46群,春季15群,分别占总群数的20.06%和20.55%。说明矮岩羊主要以2-8只的小群为主。冬季雌雄比为1∶0.64;雌幼比为1∶0.77;春季雌雄比为1∶0.72;雌幼比为1∶0.81。     

四川省巴塘县矮岩羊与斑羚冬季生境比较

2007年10～12月,在四川省巴塘县竹巴笼自然保护区,采用样线调查法对矮岩羊和斑羚冬季生境进行研究,利用卡方检验和Mann-Whitey U检验分析其生境选择差异.结果表明,矮岩羊对17种生境因子有选择性,倾向选择中等以上避风性,石质或便石质活动基底,灌丛盖度10%～40%、种数>4种、高度>100 cm,草种数>5种、高度<20 cm或>40 cm,坡度>60°的南坡或西坡,隐蔽级<30%或>60%,水源距离>500 m,裸岩距离<2m,林缘距离1000～1 500 m,1级风,海拔高度2 600～2 800 m,人为干扰距离500～1 000 m,动物干扰距离80～150 m的生境.斑羚对15种生境因子有选择性,倾向选择上坡或山脊坡位,灌丛盖度10%～40%、种数>5种、高度>100 cm,草种数4～5种、高度>40 cm,坡度>60°的南坡或东南坡,南风,隐蔽级>60%,林缘距离<1 500 m,海拔高度>2 800 m,水源距离>1 000 m,人为干扰距离>1 000 m,动物干扰距离80～150 m的生境.因子分析表明,影响矮岩羊生境选择的主要因子为人为干扰距离、海拔高度、林缘距离、水源距离、灌丛高度、隐蔽级、风级和动物干扰距离等生境因子,而影响斑羚生境选择的主要因子为人为干扰距离、海拔高度、林缘距离、水源距离、坡位、灌丛盖度、灌丛高度、隐蔽级、坡向和风向生境因子.虽然两物种在资源生态位上存在部分重叠,但在生境选择利用和空间生态位上皆存在很大差异.     

Molecular evidence for the subspecific differentiation of blue sheep (Pseudois nayaur) and polyphyletic origin of dwarf blue sheep (Pseudois schaeferi)

Blue sheep (Pseudois nayaur), a Central Asian ungulate with restricted geographic distribution, exhibits unclear variation in morphology and phylogeographic structure. The composition of species and subspecies in the genus Pseudois is controversial, particularly with respect to the taxonomic designation of geographically restricted populations. Here, 26 specimens including 5 dwarf blue sheep (Pseudois schaeferi), which were collected from a broad geographic region in China, were analyzed for 2 mitochondrial DNA fragments (cytochrome b and control region sequences). In a pattern consistent with geographically defined subspecies, we found three deeply divergent mitochondrial lineages restricted to different geographic regions. The currently designated two subspecies of blue sheep, Pseudois nayaur nayaur and Pseudois nayaur szechuanensis, were recognized in the phylogenetic trees. In addition, the Helan Mountain population showed distinct genetic characteristics from other geographic populations, and thus should be classified as a new subspecies. In contrast, dwarf blue sheep clustered closely with some blue sheep from Sichuan Province in the phylogenetic trees. Therefore, dwarf blue sheep appear to be a subset of Pseudois nayaur szechuanensis. After considering both population genetic information and molecular clock analysis, we obtained some relevant molecular phylogeographic information concerning the historical biogeography of blue sheep. These results also indicate that western Sichuan was a potential refugium for blue sheep during the Quaternary period.     

矮岩羊(Pseudois schaeferi)行为谱及PAE编码系统

2007年3～12月,对四川竹巴笼自然保护区的矮岩羊（Pseudois schaeferi）进行了行为谱工作的研究,建立了矮岩羊行为谱及其PAE（posture,act and environment）编码系统。研究分辨和记录了矮岩羊的11种姿势,83种动作和118种行为,还区别了各种行为在雄性、雌性和幼体之间的相对发生频次以及发生季节。     

贺兰山岩羊（Pseudois nayaur）集群特征的季节变化

2004年11月～2005年10月,在贺兰山对岩羊(Pseudois nayaur)的集群行为进行了研究,将其集群类型划分为雌性群、雄性群、雌雄群、母仔群、混合群和独羊6种类型.共观察到岩羊1 023群次,计4 866只次,平均群大小为(4.86±2.54)只,最大的群为51只,最小的为独羊.其中,母仔群459群(44.87%)为最多的集群类型,其余为混合群(20.72%)、雄性群(14.86%)、独羊(9.09%)、雌雄群(5.57%)、雌性群(4.89%).母仔群出现的频次在4个季节均最高,除母仔群外,春季雄性群出现的频次最高,而夏、秋、冬季都是混合群出现的频次最高,不同类型集群出现频次的季节间差异极显著.在4个季节中都以2～5只的群居多,其出现的频次占各季节群数50%以上,不同季节群大小差异极显著,而不同集群类型群大小季节间不存在显著差异.除独羊外,不同季节混合群大小差异极显著,母仔群、雌性群大小差异显著,而雄性群、雌雄群大小无显著差异.研究结果显示,贺兰山岩羊集小群是其显著特点,随着季节的变化,其集群类型、集群大小均会发生一定的变化.     

Feeding habitats of blue sheep (Pseudois nayaur) during winter and spring in Helan Mountains, China

The feeding habitat selection of blue sheep (Pseudois nayaur)was studied by direct observation method in the Helan Mountains,China during winter (from November to December)and spring (from April to June)from 2003 to 2004.We established 25 line transects to collect information on feeding habitats used by blue sheep.Blue sheep in the study area preferred mountain savanna forests,a habitat dominated by Ulmus glaucescens,with medium tree density (＜4 individuals/400 m2),moderate tree height (4-6 m),higher shrub density (＞5 individuals/100 m2),higher shrub (＞1.3 m),higher food abundance (＞50 g),moderate distance to human disturbance (＜500 m),and mild distance to bare rock (＜2 m).Such habitats characterized by 12 ecological factors were preferred as feeding areas by blue sheep during winter.Similar to habitat selection by the species during winter,blue sheep also showed a preference for mountain savanna with tree dominated by Ulmus glaucescens and medium tree density (＜4 individuals/400 m2)during spring.Nevertheless,blue sheep preferred medium tree height (＜6 m),moderate tree density (5-10 individuals/100 m2),medium shrub height (1.3-1.7 m),higher food abundance (＞100 g),moderate altitude (＜2 000 m),moderate distance to water resource (＜500 m),and medium hiding cover (50%-75%)during spring.Selection of the feeding habitats by sheep showed a significant difference in vegetation type,landform feature,dominant tree,tree height,shrub density,distance to the nearest shrub,food abundance,slope direction,slope degree,distance to water resource,and hiding cover between winter and spring.Results of principal components analysis indicated that the first principal component accounted for 24.493%of the total variance among feeding habitat variance during winter,with higher loadings for vegetation type,dominant tree,tree height,distance to the nearest tree,shrub density,shrub height,altitude,distance to water resource,and distance to human disturbance.In spring,the first principal components explained 28.777%of the variance,with higher loadings for vegetation type,distance to the nearest tree,shrub height,distance to the nearest shrub,food abundance,altitude,and distance to human disturbance.     

Genetic distinctiveness of endangered dwarf blue sheep (Pseudois nayaur schaeferi): evidence from mitochondrial control region and Y-linked ZFY intron sequences

To elucidate the controversial systematic relationship of blue sheep (Pseudois nayaur) and endangered dwarf blue sheep, we sequenced part of the mtDNA control region and Y-linked ZFY intron, and carried out phylogenetic analyses. Mitochondrial results revealed that the dwarf blue sheep is a strongly supported monophyletic group, with an average of 12.21% sequence divergence from the blue sheep. This is the first genetic evidence for the distinctness of the dwarf blue sheep. ZFY intron results showed an average of 0.51% sequence divergence, and one shared haplotype between the dwarf blue sheep and blue sheep. By analyzing an expanded data set that incorporated ZFY intron sequences of two additional Ovis (sheep) species-O. nivicola and O. ammon--we demonstrated that ZFY intron provides good resolution at the species and genus levels. The ZFY intron sequence divergence between dwarf blue sheep and blue sheep was comparable to that within the two Ovis species. Moreover, we found intraspecific sequence variation in ZFY intron for all three species examined. We propose that dwarf blue sheep be designated as a subspecies of blue sheep, P. n. schaeferi.