同种竞争压力对小泡巨鼠贮藏油茶种子行为的作用分析

2002年11～12月,在四川省都江堰地区的亚热带常绿阔叶林内利用人工修建的半自然状态围栏进行实验,研究了小泡巨鼠在有同种竞争存在条件下对油茶种子的埋藏行为。结果表明,小泡巨鼠在有竞争存在条件下,显增加了埋藏油茶种子的量。这一结果支持了“竞争的存在刺激鼠类埋藏”的假说。同时,研究结果表明,小泡巨鼠在有竞争存在条件下,显增加了对埋藏种子的搬运距离,每个贮藏点埋藏种子的数量也有所增加,同时埋藏的生境更多地偏向于遮蔽较好的微生境(草丛底层、灌丛下层)中。这些行为策略有可能有利于种子被埋藏植物的种群扩散。在讨论中,我们还通过比较鸟类和兽类在感觉器官上的差别,分析它们在有竞争存在条件下所采取的不同贮食策略。     

小泡巨鼠(Edwards'rat)一新亚种——海南小泡巨鼠

海南岛中南部山地林区产的小泡巨鼠(Rattus edwardsi)与分布于华南地区的模式亚种(R.e.edwardsi)、分布于四川的亚种(R.e.gigas)明显不同,与国外产的马来半岛亚种(R.e.ciliatus)、苏门答腊亚种(R.e.setiger)及苏门答腊西部亚种(R.e.siporanus)亦有明显的差别,经研究为一新亚种,定名为小泡巨鼠海南亚种Rattus edwardsi hainanensis Xu et Yu subsp.nov.。     

小泡巨鼠对森林种子选择和贮藏的观察

小泡巨鼠是四川省都江堰林区一种占优势的鼠种,取食多种林木种子和果实,可能影响这些树种的更新。于2001年秋季,调查了小泡巨鼠对栓皮栎、袍树、栲树、石栎、青冈和油茶等6种重要林木种子的选择和贮藏,并初步探讨了其对森林更新的影响。结果表明,小泡巨鼠对上述6种林木种子有很强的选择性,种子的营养价值和单宁含量是影响其选择和贮藏的主要因素。小泡巨鼠喜好取食和贮藏单宁含量较低的栲树、油茶和石栎种子,而不喜好取食和贮藏单宁含量较高的袍树、青冈和栓皮栎种子。小泡巨鼠在围栏内分散贮藏了部分种子(特别是石栎和油茶种子),且绝大部分贮藏点仅有1粒种子。小泡巨鼠对种子的选择和贮藏可能对有关林木的更新产生积极影响。     

金华北山三种啮齿动物身体热值、脂肪和水分含量的研究

研究了浙江金华３种啮齿动物的身体热值,脂肪含量和水分含量。成年社鼠、褐家鼠和白腹巨鼠生物量热值季节变动范围分别为６．２０９７－７．６５７ＫＪ／ｇ,６．１５３－７．０９６ＫＪ／ｇ,６．１９９－１２．０３３ＫＪ／ｇ;水分含量为６６．６４％－６９．７５％,６７．４８％－７０．１９％,５４．６４％－７２．３７％;灰分含量不存在季节差异,年平均值分别为１２．５０％,１２．２３％,１０．４９％。神鼠脂肪含量春     

Volatile components of lemur scent secretions vary throughout the year

Olfactory signals can communicate a wide variety of information and are very important in many mammalian species. However, little is known about the olfactory communication of primates. This study used gas chromatography to examine the volatile components of the anogenital gland secretions of wild Milne-Edward's sifaka, Propithecus edwardsi (Primates, Indriidae) (n = 17), captured in Ranomafana National Park, Madagascar. We compared scent swabs of animals and examined differences between social group, age class, sex, and season. The only identified differences in the volatiles were between swabs from the different seasons; all other categories were statistically indistinguishable.     

Isolation of sixteen autosomal loci and a sex-linked polymorphic microsatellite locus from the Milne-Edwards' sportive lemur (Lepilemur edwardsi)

We isolated 21 microsatellites from the Milne-Edwards' sportive lemur, Lepilemur edwardsi. Eighteen microsatellite sequences possessed sufficient flanking DNA for primer design. Seventeen loci amplified and were found to be polymorphic displaying two to 17 alleles in 32 unrelated individuals from a population from the National Park of Ankarafantsika in northwest Madagascar. One locus (Led-12) was found to be sex linked located on the X chromosome and can be used to sex-type 40% of female L. edwardsi lemurs. These 17 loci were characterized to investigate family structure and the phylogeography of L. edwardsi.     

Lemur habitat and dental senescence in Ranomafana National Park, Madagascar

Not only can teeth provide clues about diet, but they also can be indicators of habitat quality. Conspecific groups living in different habitats with different kinds of foods may exhibit different rates of dental attrition because their teeth are less well adapted to some foods than to others. Ecological disequilibrium describes the situation in which animals live in habitats to which they are relatively poorly adapted. We test whether dental senescence, the wear-related decrease in dental functionality that is associated with decreased survival of infants born to older Propithecus edwardsi females, can be explained by ecological disequilibrium. Specifically, we compare the rates of dental wear in sifaka groups living in nearby habitats that differ in the degree of anthropogenically induced disturbance. We hypothesize that sifakas living in disturbed areas have an unusual rate of tooth wear compared to those living in a more pristine area, and that dental senescence is a consequence of an atypically high wear rate in a degraded habitat. To test whether habitat quality affects tooth wear more generally, we compare rates of use-wear in two subsets of Microcebus rufus living in either relatively undisturbed or disturbed habitats. Contrary to our predictions, we did not detect different rates of tooth wear in disturbed versus undisturbed habitats for either species and consider that reproductively detrimental dental senescence in P. edwardsi females is unlikely to be a pathological consequence of ecological disequilibrium.     

种子类别和埋藏深度对雌性小泡巨鼠发现种子的影响

2001年9～12月,在四川省都江堰林区实验围栏内研究了栓皮栎、袍树、栲树、石栎、青冈和油茶种子与6种埋藏深度对小泡巨鼠雌性成体发现埋藏种子的影响。结果表明：1)由于不同种子在种子大小、营养价值和单宁含量等存在差异,雌性小泡巨鼠对个体最大的石栎种子发现率最高,油茶(脂肪含量高)和栲树(单宁含量低)次之,单宁含量较高的袍树、青冈和栓皮栎则较低;2)埋藏深度与雌性小泡巨鼠发现栓皮栎种子的比例呈显负相关,即随着埋藏深度增加,小泡巨鼠发现埋藏种子的比例则减少。     

The volatile organic compounds of introduced and native dung and carrion and their role in dung beetle foraging behaviour

1. The decomposition of biological material produces a plethora of volatile organic compounds (VOCs), which are implicated in the foraging behaviour of coprophagous and necrophagous insects. Dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) have an acute olfactory system used to locate food resources. Accordingly, identification of food resource VOCs potentially used in food location is integral to understanding dung beetle foraging ecology. 2. In this study, volatile emissions from dung and carrion of native and introduced animals in New Zealand were analysed using solid‐phase microextraction (SPME) and gas chromatography‐mass spectrometry (GC‐MS). Volatile profiles were compared via principal component analyses (PCAs) and cluster solutions based on attractiveness using canonical discriminant analysis (CDA). 3. A total of 115 compounds were detected from 21 food types. Statistical analyses showed that dung and carrion volatile profiles clustered according to attractiveness to the dung beetle Saphobius edwardsi, and that different dung types formed distinct clusters and grouped separately from carrion. 4. This study suggests that volatile profiles emitted by food resources used by dung beetles are complex, producing distinct odours, which potentially mediate foraging decisions.