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1.
  1. Analyses of the distributions of northern Melanesia's avifauna have helped researchers formulate major theories of evolution, speciation, and biogeography. In comparison, the region's mammalian fauna has been the subject of few empirical analyses of biogeography. Knowledge of mammalian biogeography is needed to formulate sound conservation strategies for mammals in the region and will help further advance these theories.
  2. We aim to assess the relative importance of biogeographic variables to mammalian zoogeography in northern Melanesia and empirically describe patterns of species richness.
  3. Using published literature, museum data bases and our own surveys, we compiled mammal inventories for 75 islands found within northern Melanesia (comprising the Admiralty, Bismarck, D‘Entrecasteaux, Louisiade, Solomon, and Trobriand Archipelagos). We used direct comparisons of family compositions and Ochiai and endemism indices to compare mammal assemblages between island groups and a defined New Guinea source pool region. Generalised linear models and non‐parametric multivariate analyses were used to identify, and rank, the importance of local and regional scale abiotic variables for mammalian species richness.
  4. Northern Melanesia's islands are depauperate in marsupials and have a moderate diversity of insectivorous bats and a diversity of pteropodid bats that exceeds that known to occur in the adjacent northeastern area of New Guinea. The Solomon Islands are conspicuous for their outstandingly high mammalian endemism.
  5. The mammalian fauna of northern Melanesia's islands was related primarily to island size and secondarily to isolation. Island size best explained inter‐island variation in total mammal species richness and bat species richness. The linear distance to New Guinea best explained the species richness of non‐volant mammals. Our results reveal islands that are in need of survey focus because their mammal inventories are lower than expected for their size, and we highlight areas of endemism where conservation actions might be prioritised to prevent species extinctions.
  相似文献   
2.
Towards a generalized biogeography of the Southern Ocean benthos   总被引:1,自引:0,他引:1  
Aim To investigate whether the biogeographical regions proposed by J. W. Hedgpeth and widely adopted by other authors hold true, are an oversimplification or with further data might show a unified Antarctic province. Location Southern Hemisphere. Methods The distributions of 1318 species of bivalves, 4656 species of gastropods, 1465 species of cheilostome and 167 species of cyclostome bryozoans were analysed for 29 regions in the Southern Hemisphere, including South American, South African, Tasmanian, New Zealand, sub‐Antarctic and Antarctic regions. We present data on species richness, rates of endemism, patterns of radiation, faunal similarities and multivariate biogeographical analyses. Results The most striking pattern to emerge from our data set of species counts per region was a strong east–west hemispheric asymmetry, with high species numbers in New Zealand, Tasmania and South Africa and low numbers in South America. In contrast, no difference was found in richness between the east and west parts of the Southern Ocean. We compared findings in our model taxa with published data on ascidians, cephalopods and pycnogonids. Further evidence of strong faunal links between the Antarctic and South America is reported in this study, although we found little evidence for a biogeographical relationship between the Antarctic or South America and New Zealand/Tasmania. Strong evidence exists for a long‐term influence of the Antarctic Circumpolar Current upon the distribution of Southern Ocean benthos. This is demonstrated by the reduced prevalence of South American species in the Antarctic and sub‐Antarctic with increasing distance from South America in the direction of the current. Three of our four study taxa (bivalves, cheilostomes and cyclostomes) show the Southern Ocean as a ‘single functional unit’ with no evidence for a biogeographical split between east and west. Main conclusions Unlike the biogeographical schemes previously proposed, we show that biogeographical regions in the Southern Ocean differ depending upon the class of animals being considered. Despite this we suggest that some general rules are viable, including species endemism rates of around 50%, a single Antarctic province and a definite distinction between the sub‐Antarctic islands influenced by South America and those of New Zealand.  相似文献   
3.
Most megadiversity regions lack basic wild animal diversity information such as species lists. This absence of basic knowledge restricts the development and effectiveness of conservation action plans, which are urgently needed for animal groups such as amphibians, the most threatened vertebrate group in the world. In this study, we estimated Brazilian anuran diversity based on species range distribution shapes and evaluated factors that likely affect species lists, such as current taxonomy knowledge, current number of specimens collected in each region, biome characteristics, and anuran size (snout–vent length). We were able to demonstrate differences among the distributional patterns of species within each biome and each Brazilian federative state and among certain factors that influence their diversity, such as latitudinal variation. In this integrative study, we provide zoogeographic information about the richest (in terms of anuran biodiversity) country in the world (at least 849 described species, about 60% of which are endemic), which may be fundamental to future conservation actions in Brazil.  相似文献   
4.
Rotifers of the Antarctic and Subantarctic   总被引:3,自引:2,他引:1  
An assessment of the distribution of rotifers in the Antarctic and Subantarctic is attempted.  相似文献   
5.
Soh  Ho Young  Suh  Hae-Lip  Yu  Ok Hwan  Ohtsuka  Susumu 《Hydrobiologia》2001,448(1-3):203-215
The demersal calanoid copepods Pseudodiaptomus nihonkaiensis Hirakawa, 1983 and P. poplesia (Shen, 1955) are redescribed from Korean waters. Using scanning electron microscopy, we examine the morphology of the female genital systems of four species of Pseudodiaptomus (P. inopinus, P. marinus, P. nihonkaiensis and P. poplesia), revealing interspecific differences. The zoogeography of these four species is discussed.  相似文献   
6.
7.
中国不同地理区域鸟兽物种丰富度的相关性   总被引:9,自引:0,他引:9  
生物类群之间物种丰富度的相关性研究是当前物种多样性研究中的热点问题之一,目前,中国尚无相关的研究报道。我们收集了中国三种区域类型:动物地理亚区、行政区和保护区的鸟兽名录,分析了行政区与保护区、动物地理区和经纬度带中鸟兽物种数比值及其相关性。 结果表明:不同区域、动物地理区和经纬度带中鸟兽物种数都显著相关。保护区尺度鸟兽物种 数的相关系数为0.818和动物地理区中的华北区为0.768,其他所有区域和地理区域的鸟兽物 种数的相关系数都高于0.850。因此,鸟兽物种数的相关关系在一定程度上具有预测价值。我们发现不同区域鸟兽物种数比值无显著性差异;但是,不同区域间鸟兽物种数 比值差异显著。该比值在中国呈中间低四周高的分布趋势,其中东北地区最高。我们还利用历史累积调查数据与非历史累积调查数据进行了鸟兽物种数比值及其相关性分析,发现利用累积数据计算的相关性低于非累积数据计算的相关性,但利用累积数据计算的鸟兽物 种数比值高于非累积数据计算的比值。最后,探讨了为什么鸟类与兽类的物种数目会相关。我们根据物种-面积公式,S=CAZ,导出了两个生物类群物种丰富度的相关关 系式。利用全国不同区域数据拟合,得到Z1/Z2=0.913,Z1/Z2接近于1。于是 ,C1/C2可视为近似等于Ram。本研究可推广到其他不同生物类群物种。物种数量的相关关系为快速评估区域的物种多样性提供了一条途径。  相似文献   
8.
R. C. Hart 《Hydrobiologia》1994,272(1-3):163-183
The temperature-dependence of development was studied in two ecologically divergent freshwater calanoids, Metadiaptomus meridianus (Douwe) and Tropodiaptomus spectabilis (Kiefer). Egg durations were determined between 10 and 35 °C, and food satiated post-embryonic development times between 12 and 32 °C. All responses were basically inverse monotonic functions of temperature, adequately described by Blehrádek's equation. M. meridianus generally developed faster than T. spectabilis. Its egg development was faster at all temperatures, and while its naupliar durations were shorter only up to ± 15 °C, its overall post-embryonic development was more rapid up to ± 24 °C in females and ± 28 °C in males. Relatively speaking, however, T. spectabilis is clearly more warm-adapted than M. meridianus. The respective distributions (warm subtropical lowlands vs cooler uplands) of these copepods in the southern African subcontinent, as well as reversible switches between these species observed in two Natal impoundments are consistent with their contrasting thermal responses, although additional considerations apply in respect of the species alternations. T. spectabilis was replaced by M. meridianus in L. Midmar in spring 1981 and 1989, and in L. Albert Falls in spring 1990. Reciprocal replacements occurred in Midmar in autumn 1984, and in Albert Falls in late summer 1991. Both spring switches in Midmar coincided with cool spring temperatures, although the consequent shifts in growth rate advantage predicted from the measured temperature-duration responses only partly explain the switches in this warm-temperate reservoir. Parasitism of T. spectabilis by an ellobiopsid was observed during both switching events in Midmar, and perhaps augmented the change, although its effects on the host are indeterminate. Both species showed exactly parallel temporal changes in fecundity during the recent switches in both reservoirs, indicating closely similar trophic niches in the adults at least, and mitigating the possibility of trophic influences as determinants of the replacement. A dramatic but inexplicable increase (around 50% at 20 °C) in the development time of T. spectabilis was noted between 1988 and 1990, and perhaps contributed too.The protracted historical dominance of T. spectabilis in thermally suboptimal conditions in Midmar is ascribed to a general competitive superiority presumed from its K-selected attributes, in contrast to the r-selection evident in M. meridianus. This alternation between species with contrasting life styles is of fundamental ecological interest. Studies on Albert Falls, commenced in 1989, suggest an even greater competitive superiority of T. spectabilis, in keeping with the warmer conditions in this larger sister reservoir below Midmar.  相似文献   
9.
10.
谭恩光 《生态学报》2008,28(12):6272-6281
综述中国蛭类研究如下内容:(1)生态学.山蛭生态学,包括山蛭的生态分布,海南山蛭(H. hainana)的种群动态,对温度、土壤湿度和pH值的适应,以及对温、光、湿的综合反应和人类经济活动对其种群数量的影响;山蛭行为生态学,山蛭的运动包括慢缩短、快缩短、身体摆动和转动、洗刷运动、亲吻运动、觅食行为6程序,影响山蛭行为的一些因素以及对环境因素刺激的生态学意义;淡水水蛭生态学,包括浙江水田蛭类生活习性、广州水生光润金线蛭种群数量动态与水体化学因子关系、广州水田吸血菲牛蛭生活水体化学环境;山蛭和水生吸血菲牛蛭的觅食、生长动态、生命周期和生殖生物学;(2)形态学、分类学和动物地理学.形态学包括山蛭机能组织学、山蛭器官系统解剖;分类学,中国蛭类动物有2亚纲(蛭蚓亚纲、真蛭亚纲)、3目(蛭蚓目、吻蛭目、无吻目)、9科、33属、111种,占世界蛭类物种数约1/6;动物地理学,包括世界山蛭科属动物地理,中国山蛭科动物地理、中国医蛭科动物地理.(3)蛭类的防治和驱避,淡水吸血蛭类防治所用农药种类,不同农药对海南山蛭的毒力( LD50、LD95)及使用,并比较了12种驱避剂对海南山蛭的驱避效果.(4)蛭类的医学利用,蛭素是蛭类唾液腺分泌的一种抗凝物质,蛭素有水蛭素(Hirudin)、山蛭素(Haemadin)和吻蛭素(Hementin).记述了蛭素的分离、纯化和功能以及有关分子生物学内容.  相似文献   
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