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1.
江西省鄱阳湖自然保护区昆虫区系初探   总被引:6,自引:2,他引:4  
据对有较详细分布资料的220种昆虫的分析,鄱阳湖自然保护区昆虫属东洋界范畴,但已接近古北界南缘;昆虫种类形成了古北,东洋两大区系成分交叉重叠现象.亦是两大区系交叉过渡地带。在我国东部地区,与鄱阳湖共有种的分布规律为随着纬度的增高而递减。本文论述了鄱阳湖33种昆虫在我国东半部分布的南北限。  相似文献   

2.
本文就(虫+责)科昆虫的起源,各亚科、族及属的分布特点进行了分析和总结;并根据各属的世界分布情况,将其分为8种类型。文中还就中国(虫+责)科昆虫的地理分布及特点作了初步的探讨,结果表明:在我国已知的2亚科4族20个属中,东洋区分布的有10个属,其中有3个属仅分布于我国;古北区分布的有1个属;东洋-古北区分布的有3个属;东洋-新北区分布的有1个属;东洋-古北-新北区分布的有4个属;东洋-古北-新北-非洲区分布的有1个属。此外,(虫+责)科昆虫在中国的一个主要分布特点就是多数种类集中分布于华中区、华南区和西南区;而华中区则很可能是(虫+责)科种类的分化中心,并以此为中心向其他区扩散。  相似文献   

3.
横断山区昆虫区系初探   总被引:19,自引:0,他引:19  
王书永 《昆虫学报》1990,33(1):94-101
1981—1984年,中国科学院青藏高原科学考察队在我国西南部的横断山区进行了大规模的多学科综合考察,收集昆虫标本17万多号.横断山区特殊的自然地理条件孕育着独特的昆虫区系.种类繁庶、成分复杂,特有种,尤其高山特有种相当丰富,物种分化显著,并具有地域上的狭布性,构成本区昆虫区系特征.作者根据古北、东洋、高山特有三种主要成分的分布,试提出古北、东洋两大区系在本区的分异界线.典型东洋区系成分一般限于海拔2,800—3,000m以下地区,约与亚热带常绿阔叶林分布上线一致.  相似文献   

4.
珠江的鱼类区系及其动物地理区划的讨论   总被引:34,自引:7,他引:27  
本文根据珠江水系实地调查的结果,对珠江淡水鱼类区系的组成、形成原因及其在动物地理区划中的位置进行了讨论,否定了前人将南岭山脉作为东洋区和古北区在东亚的分界线的观点,认为这两个大区的界线应向北推移到秦岭山脉,并且指出珠江水系的鱼类区系元大部分隶属于东洋区的南东亚亚区,而其西江上源的一小部分应划归南亚亚区。  相似文献   

5.
陕西秦岭太白山北坡食蚜蝇科昆虫区系调查   总被引:4,自引:1,他引:3  
霍科科  任国栋 《昆虫知识》2006,43(5):700-705
鉴定出秦岭太白山北坡食蚜蝇科昆虫2亚科,10族,35属,61种,包括中国新记录种3种:亮黄斑食蚜蝇Xanthogramma laetum(Fabricius)、无饰缩颜蚜蝇Pipiza inornataMatsumura和阿尔泰颜突蚜蝇Portevinia altaica(Stackelberg),陕西省新记录种16种。太白山北坡食蚜蝇科昆虫的区系成分以古北、东洋区共有种为主体,古北区成分略占优,东洋区成分占有一定比例;从属的分布类型看,多区属比例高达57.14%,单区属均为古北区成分,所占比例最低。太白山北坡食蚜蝇科昆虫区系具有明显的过渡性,混杂性和复杂性。  相似文献   

6.
横断山区蚜虫区系的特异性与历史渊源   总被引:4,自引:1,他引:3  
文章系统分析了横断山区蚜虫区系的特异性,主要表现在:区系成分的复杂性、古北与东洋成分的交融性、区系组成的特有性和物种分布的间断性.进一步结合地质历史事件对横断山区蚜虫区系的历史渊源及其特异性演化进行了初步讨论.根据蚜虫类分布特点,建议古北区和东洋区在横断山区的分界线南移至丽江一线;横断山区蚜虫和其他地区的间隔分布可能是由地质历史上板块运动和青藏高原的隆升及第四纪冰期-间冰期的循环往复造成的;横断山区蚜虫区系是一个复合区系,同其他动物地理区划如新北区、澳洲区、非洲区等的蚜虫区系都有密切的历史渊源,青藏高原和横断山区的隆起及第四纪冰期-间冰期的循环往复又使得本区蚜虫区系有着独特的演化历程,从而造成了本区蚜虫区系的特有性.  相似文献   

7.
湖北大巴山东部蚤类区系组成及垂直分布   总被引:5,自引:0,他引:5  
采用常规与沿雪线调查方法,对大巴山东部具代表性的7个不同海拔梯度及6个不同生境类型,连续进行了11年调查和研究。结果表明:1)在所获得的8科28属51种9 974只蚤类中,有25种隶属于古北界,占49.02%,21种属于东洋界,占41.18%,5种广布,占9.80%; 经个体数量区系处理,古北和东洋两界蚤类区系数量(37.97%,50.30%)并不完全与物种区系相吻合,但东洋蚤类区系数量与古北物种区系相当;2)大巴山东部蚤类垂直分布的区系特点是,1 500 m以下东洋成分占绝对优势,1 600~2 300 m古北成分达44.82%~56.41%,但个体区系数量却在33.47%~60.16%之间,物种区系成分与数量区系分布并不完全一致; 一些东洋界特有指示性质的巴山盲鼠蚤和它的寄主猪尾鼠,仍可分布到这一地带;当海拔上升到2 600 m,古北成分已稳定达55.00%,此地带已不见东洋界特有指示性质的巴山盲鼠蚤和它的寄主猪尾鼠的踪迹,当海拔上升到2 800~2 980 m,古北成分和个体数量分别已达65.00%和89.51%;3)在大巴山东部51种蚤类中,有24种在秦岭有分布,占秦岭已知34种的70.58%,两座山系古北成分也相当,分别为49.02%及52.94%。最后按区系、宿主动物、植被带谱和地理状况相近原则,对张金桐等(1989)对秦岭南坡的蚤类海拔高度划线1 000~2 000 m进行修订,并上移至2 600 m左右地带,修订后的划线,其具体位置及走向大体与暗针叶林的下限保持一致。此线以上,无论蚤种或是数量都以古北界成分为主,低于此线,古北、东洋成分和一些特有指示性质的种类相互渗透。  相似文献   

8.
中国南方第四纪哺乳动物群所反映的自然环境变迁   总被引:5,自引:1,他引:4  
<正> 现代哺乳动物的地理分布,显示出世界各大陆的动物区系同地球上气候分带是密切相关,根据我国现代动物区划(郑作新、张荣祖,1959),可将全国分二界,七个基本区,最主要是东洋与古北二界。南方地区可以划分为西南、华中及华南三亚区,这三亚区基本上是属于东洋界。一些属于东洋界的属种,仅分布于长江以南地区,而华北地区分布很少或  相似文献   

9.
章士美 《昆虫学报》1965,(4):411-419
本文系以某些主要农业害虫的分布资料为依据,来讨论古北、东洋两地区在我国秦岭以东的分界线问题。 全文分为四个部分,第一部分着重介绍中外学者对于这条界线摆法的几种不同意见。第二部分将194种农业昆虫在我国秦岭以东的交杂渗透情况,依长城、黄河、淮河、长江、南岭等五条界线,列举它们分布区(或为害区)的南限或北限。第三部分讨论了古北、东洋两地区在豫鄂一带的分界线,提出应摆在淮河以南,即将河南南部的南阳盆地及信阳专区,亦划入东洋区中。第四部分进一步讨论了两地区在江、浙一带的分界线问题,则主张划在长江北岸,比较妥当。  相似文献   

10.
为揭示四川鞍子河国家级自然保护区及邻近地区蚂蚁区系特征,2016年6—7月采用样地调查法研究了该区域的蚂蚁区系。结果显示:共采集蚂蚁6亚科32属62种;在世界动物地理界中,分布于东洋界的共32属,东洋界分布种最多(62种),新热带界种最少(3种);在中国动物地理区中,西南区种最多(62种),蒙新区种最少(4种);在种的分布型中,东洋-古北界共有种最丰富(36种,58.1%),东洋-古北-新北界共有种等3个分布型物种贫乏(1种,1.6%)。保护区及邻近地区蚂蚁区系具有东洋界向古北界过渡的特征,同时具有西南区、华南区、华中区、华北区成分汇聚特点,具有典型西南区特征。  相似文献   

11.
1. The isozymes of lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and glucose-phosphate isomerase (GPI) of three species of Italian ictalurids: Ictalurus sp., I. nebulosus marmoratus, and I. punctatus, were analyzed. 2. Isoelectric focusing (IEF) was applied to polyacrylamide gel plates, and the isozymes revealed by means of specific histochemical staining. 3. Species-specific monomorphic patterns were found for LDH. 4. In contrast, MDH and GPI have the same patterns in I. sp. and I. nebulosus marmoratus and different patterns in I. punctatus. 5. Comparison of the isozymatic patterns of the three species clearly showed the close relationship between I. sp. and I. nebulosus marmoratus and the relative taxonomic distance of I. punctatus, and thus the early detachment of this last species from a presumptive common ancestral lineage.  相似文献   

12.
Electrophoretic and isoelectrophoretic behaviour of the hemoglobins of Italian freshwater Ictalurids was analysed. Multiple and polymorphic hemoglobin patterns were found in Ictalurus sp. (I. nebulosus nebulosus?, I. melas?); multiple and monomorphic patterns in I. n. marmoratus and I. punctatus. Hypotheses are advanced for further investigation of the question.  相似文献   

13.
Understanding the origins of species richness patterns is a fundamental goal in ecology and evolutionary biology. Much research has focused on explaining two kinds of species richness patterns: (i) spatial species richness patterns (e.g. the latitudinal diversity gradient), and (ii) clade-based species richness patterns (e.g. the predominance of angiosperm species among plants). Here, I highlight a third kind of richness pattern: trait-based species richness (e.g. the number of species with each state of a character, such as diet or body size). Trait-based richness patterns are relevant to many topics in ecology and evolution, from ecosystem function to adaptive radiation to the paradox of sex. Although many studies have described particular trait-based richness patterns, the origins of these patterns remain far less understood, and trait-based richness has not been emphasised as a general category of richness patterns. Here, I describe a conceptual framework for how trait-based richness patterns arise compared to other richness patterns. A systematic review suggests that trait-based richness patterns are most often explained by when each state originates within a group (i.e. older states generally have higher richness), and not by differences in transition rates among states or faster diversification of species with certain states. This latter result contrasts with the widespread emphasis on diversification rates in species-richness research. I show that many recent studies of spatial richness patterns are actually studies of trait-based richness patterns, potentially confounding the causes of these patterns. Finally, I describe a plethora of unanswered questions related to trait-based richness patterns.  相似文献   

14.
Low-angle X-ray diffraction patterns of peripheral nerve myelin after modification by either rehydration in various solutions or by chemical treatment have been recorded. These X-ray patterns and the previously reported modified nerve myelin patterns demonstrate that nerve myelin has at least five different states: the normal state, condensed state I and II and separated state I and II. There are two membranes per unit cell in the normal state and in states II whereas there is one membrane per unit cell in states I. Under certain conditions normal nerve can go reversibly into either of states II. With continued treatment the nerve myelin structure moves irreversibly from state II to state I and, once in state I, the nerve myelin layers cannot return to the normal state. Our results demonstrate that there is a reversible transformation between condensed state I and separated state I. Fourier profiles of nerve myelin in the normal state, condensed state I and separated state I are presented.  相似文献   

15.
The surface protein array of Aeromonas salmonicida (or A-layer) appears, in negatively stained preparations, as two distinct patterns, type I and type II. Type I patterns were restricted to, and predominated in, darkly stained areas, whereas lighter staining regions exclusively displayed type II patterns. The type I morphology was faithfully reproduced in computer-simulated superimpositions of type II patterns, as was the intermediate transition zone frequently seen between the two patterns. Variations in the lattice constant of both patterns, presumably due to artifactual flattening, demonstrated that these patterns could not be distinguished on this basis. The conceptual model presented points to the type II pattern as the only single A-layer structural type. We propose the use of the terms type 1/type II to exclusively describe the morphological patterns that appear upon negative staining and the open/closed nomenclature to describe the conformations that a single structural type can adopt.  相似文献   

16.
Photosystem I fragments were prepared from thylakoid membranes of a blue-green alga (Anabaena variabilis) and spinach by treatment with a detergent, Triton X-100. Equatorial X-ray diffraction patterns were recorded on films for oriented specimens of thylakoid membranes and photosystem I fragments. The thylakoid membranes and photosystem I fragments gave essentially the same equatorial diffraction patterns in both Anabaena variabilis and spinach, indicating that the major X-ray scatterers in these thylakoid membranes are the molecular assembly of photosystem I. The equatorial X-ray diffraction from the photosystem I fragments of Anabaena variabilis and spinach extends to the reciprocal space of 1/7 A-1. The diffraction pattern exhibits six to nine distinct maxima though they are diffuse, indicating that the arrangement of the constituent molecules in photosystem I has a definite geometrical regularity. The radial autocorrelation functions indicate that the maximal sizes of photosystem I in these thylakoid membranes are about 100 A, and the geometrical regularity does not correspond to a crystalline order. The X-ray diffraction patterns from photosystem I fragments from Anabaena variabilis and spinach are quite similar to each other, suggesting the possibility that the molecular structures of photosystem I in Anabaena variabilis and spinach have a fundamental similarity. These diffraction patterns, however, are different from that of the chromatophore obtained from a photosynthetic bacterium, Rhodospirillum rubrum.  相似文献   

17.
The patterns of major histocompatibility complex (MHC) evolution involve duplications, deletions, and independent divergence of loci during episodes punctuated by natural selection. Major differences in MHC evolution among taxa have previously been attributed to variation in linkage patterns of class I and class II MHC genes. Here we characterize patterns of evolution in the MHC class Ia gene of Xenopus laevis in terms of polymorphism, recombination, and extent of transspecies polymorphism. We also compare these patterns to see if a correlation exists with linkage or separation of the MHC class I and class II regions as seen in amphibians and teleost fishes. In X. laevis, we find high levels of polymorphism. Also, genetic exchange is relatively frequent and occurs in intron II, reshuffling allelic forms of exons 2 and 3. Evolutionary relationships among class I alleles show an intermingling of alleles from divergent Xenopus species rather than a species-specific clustering. Results indicate that the patterns of evolution are similar to those found in salmonid fishes and are different from the mode of evolution seen in primates. Similar patterns of class Ia evolution in salmonid fishes and X. laevis suggest that nonlinkage of class I and class II regions alone is insufficient to explain some patterns of MHC evolution in salmonids.  相似文献   

18.
Myocardial ischemia/reperfusion (I/R) is the most common cause of myocardial inflammation, which is primarily a manifestation of the innate immune responses. Innate immunity is activated when pattern recognition receptors (PRRs) respond to molecular patterns common to microbes and to danger signals expressed by injured or infected cells, so called pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). The expression of various PRRs in cardiomyocytes and the release of DAMPs from cardiomyocytes subjected to I/R injury, through active mechanisms as well as passive processes, enable cardiomyocytes to generate innate immune responses. Studies in isolated heart and cardiomyocytes have confirmed the inflammatory and functional effects of cardiac PRRs especially Toll-like receptors in response to I/R-derived DAMPs, such as heat shock proteins. This review addresses the active role of cardiomyocytes in mediating innate inflammatory responses to myocardial I/R. We propose that cardiomyocytes act as innate immune cells in myocardial I/R injury.  相似文献   

19.
The stochastic firing patterns are simulated near saddle-node bifurcation on an invariant cycle corresponding to type I excitability in stochastic Morris–Lecar model. In absence of external periodic signal, the stochastic firing manifests continuous distribution in ISI histogram (ISIH), whose amplitude at first increases sharply and then decreases exponentially. In presence of the external periodic signal, stochastic firing patterns appear as two cases of integer multiple firing with multiple discrete peaks in ISIH. One manifests perfect exponential decay in all peaks and the other imperfect exponential decay except a lower first peak. These stochastic firing patterns simulated with or without external periodic signal can be demonstrated in the experiments on rat hippocampal CA1 pyramidal neurons. The exponential decay laws in the multiple peaks are also acquired using probability analysis method. The perfect decay law is determined by the independent characteristic within the firing while the imperfect decay law is from the inhibitory effect. In addition, the stochastic firing patterns corresponding to type I excitability are compared to those of type II excitability. The results not only reveal the dynamics of stochastic firing patterns with or without external signal corresponding to type I excitability, but also provide practical indicators to availably identify type I excitability.  相似文献   

20.
This article briefly reviews and provides discussion on the evidence for, and nature of, density-dependence patterns in r and K-selected species. In this review, I discuss how life-history strategies cause different nonlinear density-dependence patterns and I provide a simple modeling recommendation to incorporate nonlinear density dependence in population growth equations. Second, I discuss the importance of incorporation of environmental stochasticity and local extinction associated with nonlinear density dependence associated with life-history patterns through a novel modeling exercise. Last, I discuss the importance of considering how life-history nonlinear density dependence could affect optimal harvest yields. Though these topics are extensive, this review should spur wildlife biologists and managers to consider more inclusive population models that incorporate life-history strategies and stochasticity in their decision-making processes. © 2012 The Wildlife Society.  相似文献   

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