Reversed sexual size dimorphism in microtines: Are females larger than males or are males smaller than females?

Summary We analysed sexual size dimorphism for 21 populations of microtine rodents. Female to male size ratio varied considerably among populations from females significantly larger than males (ratio=1.18) to males larger than females (ratio=0.78). In a multiple regression analysis female to male home range size ratio explained 94% of the total variation in body size dimorphism and was the only one of eight independent variables that was selected in a stepwise regression procedure. When females are the larger sex, males have home range sizes much larger than females. We suggest that the relationship between home range size ratio and body weight size dimorphism reflects different selection pressures on males and females in competition for resources and mates.     

绒属Caryomys（Thomas，1911）地位的恢复（啮齿目：仓鼠科：田鼠亚科）

绒属Ｃａｒｙｏｍｙｓ原为Ｔｈｏｍａｓ（１９１１）命名的Ｍｉｃｒｏｔｕｓ属中的一个新亚属,Ｈｉｎｔｏｎ（１９２３）将它升格为独立属,但很快又于１９２６年否定了此属的存在,从此各国学者或认为它是属Ｃｌｅｔｈｒｌｏｎｏｍｙｓ的同物异名,或认为它是绒鼠属Ｅｏｔｈｅｎｏｍｙｓ的亚属,近７０年间再无人承认此属名。本文通过对Ｃａｍｐｍｙｓ所包含的ｉｎｅｚ和ｅｖａ两种的形态学及染色体核型进行研究,并与绒鼠属Ｅｏｔｈｅｎｏｍｙｓ和属Ｃｌｅｔｈｒｉｏｎｏｍｙｓ代表种类的相关特征进行了比较分析,结果表明,ｉｎｅｚ和ｅｖａ除在形态上与绒鼠属及属种类有一些明显差异外,在染色体核型上也有显著不同,主要表现在：ｉｎｅｚ及ｅｖａ的染色体数目２ｎ＝５４,且在常染色体中,其最大的一对染色体均为亚端部着丝粒染色体;而绒鼠属和属的染色体数目则为２ｎ＝５６,且在常染色体中无此对端部着丝粒染色体。为此,作者认为应恢复Ｃａｒｙｏｍｘｓ属的分类地位。     

A comparison of hemoglobins in five species of Microtus

The composition of tryptic peptides was determined for Hb (major or fast electrophoretic component) from four additional species of Microtus; M. p. pennsylvanicus, M. abbreviatus, M. miurus, and M. oeconomus, The amino acids from the four Hb were compared with Hb from M. p. tananaensis, and, on the basis of the combination of analyses for the several Hb. Ca 95% of the overall amino acid composition was considered. The compositions of most of the homologous peptides were identical, and two deletions in the sequence of 21 amino acids β 41–61 are believed to characterize the Hb of all four species. From differences in peptide composition the following substitutions were inferred. In the β chain, M. pennsylvanicus (2 ssp) differed from other species at two positions, 8: Ser vs Thr and 12: Thr vs Ash. In the β chain M. pennsylvanicus (2 ssp) differed from other species at two positions, β45: Phe vs Leu, and β50: Ser-Glx vs Thr. M. p. pennsylvanicus differed from M. p. tananaensis at position β88: Val-Leu vs Leu. All species showed ambiguity among the amino acids Ala-Ser-Phe-Leu centred presumably in positions β129 and β130. On the basis of an incomplete examination, the slow electrophoretic component of M. abbreviatus Hb could not be seen to differ from the fast component in its peptide map or in the general composition of its and β peptides.     

中国棕背(鼠平)亚种分化的研究(啮齿目:仓鼠科:田鼠亚科)

本文对中国山西、河北、内蒙古南部、大、小兴安岭、长白山及新疆等地区的215号棕背(鼠平)(Clethrionomys rufocanus)标本的外形和头骨的形态进行了亚种分化研究,认为分布于山西、河北、内蒙古南部棕背(鼠平)的亚种为Clethrionomys rufocanus shanseius(Thomas);大、小兴安岭及新疆地区的亚种为Cl.r.irkutensis(Ognev);而将分布于长白山地区的亚种定为一新亚种——棕背(鼠平)长白山亚种(Clethrionomys rufocanus changbaishanensis)。     

The effect of diet quality on gut anatomy in British voles (Microtinae)

Three species of British voles, the bank vole Clethrionomys glareolus, the field vole Microtus agrestis and the water vole Arvicola terrestris were maintained on diets of seed and plant leaf material to investigate changes in gut anatomy. C. glareolus and M. agrestis showed significant changes in most regions of the gut; they developed longer and heavier tracts when on a highfibre diet. This response may be important in enabling these animals to withstand seasonal changes in diet quality.     

八种沙鼠亚科和田鼠亚科啮齿动物阴茎的比较研究

本文对我国仓鼠科沙鼠亚科和田鼠亚科8种啮齿动物的阴茎进行了比较解剖学研究。分析了两亚科的沙鼠属(Meriones)、大沙鼠属(Rhombomys)、田鼠属(Microtus)和绒鼠属(Eothenomys)4个属之间以及同属的种间异同。结果证明阴茎头(包括阴茎骨和软体结构)的形态结构具有属和种的稳定性和特异性,可以作为分类学研究的重要依据。     

绒鼠类系统学研究(啮齿目:仓鼠科:田鼠亚科)

在系统综述的基础上对绒鼠属Eothenomys的分类进行了探讨,认为Eothenomys属的典型特征应力;下颌骨臼齿咀嚼面左右两侧的三角形齿环均不呈交错排列,而是两两相对,彼此相融合;二倍染色体数2m=56,全部常染色体均为端部着丝粒（T）,东方绒鼠亚属Antheliomys5种中,至少玉龙绒鼠E.proditor不属于此属不能排除恢复Antheliomys属级分类地位的可能性,同意将Caryomys独立为绒Ping属;将Craseomys shanseius Thomas,1908(=E.shanseius)订正为棕背Ping的山西亚种C.r.shanseius。台湾绒鼠Eothenomys kanoi Tokuda,1937的染色体特征与Clethrionomys属相似,不应收入绒鼠属,其分类地位待定。Clethrionomys属和Eothenomys属化石种均最早出现于早更新世,目前还不能断定此二属究竟谁起源于谁,也许它们共同起源于第三者。     

洞庭湖日本血吸虫疫区东方田鼠生化与分子遗传学标记的初步研究

目的建立东方田鼠生化与分子遗传学标记检测法.方法参考近交系小鼠、大鼠生化遗传标记检测方法,对东方田鼠某些同功酶进行活性测定.根据东方田鼠特异DNA序列,合成引物,扩增东方田鼠基因组DNA,将PCR产物回收、序列分析并进行生物信息学分析.结果东方田鼠Trf、Es-3和Ce-2三个生化位点呈现遗传多态性,而Id1、Mod-1、Car-2、Gpd-1、Gpi-1、Hbb、Es-1七个生化位点无遗传多态性.用合成的特异引物扩增东方田鼠基因组DNA,得到了丰富的多态性资料.对其中的20只东方田鼠的扩增产物进行测序并进行多序列比较,发现10个等位基因以及16个单核苷酸多态性(SNP)位点.结论初步建立了东方田鼠生化及分子遗传学标记.分子遗传学标记与生化遗传标记相比,具有杂合率高、重复性好、易于操作等优点.这些结果为深入研究东方田鼠的遗传背景、生物进化规律积累了基础资料.