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1.
生物进化论是生物科学的一门基本理论,它所研究的主要课题是:地球上的生命是如何发生的?形形色色的生物又是怎样进化而来的?人类能否通过实践和怎样通过实践控制生物的发展和进化?人民教育出版社出版的《生物进化论》(河北师范大学生物系遗传育种教研组编,1975年1月第一版)一书,对上述问题作了比较系统而简要的说明,是学习生  相似文献   

2.
生态进化论     
生态是生物与其物理环境的对立统一体,它和生物一样也存在着由低级到高级、由简单到复杂的进化历程,即生态进化(Ecological Evolution)。研究生态进化的理论称为生态进化论。生态进化的根本是生态系统的进化,即系统内部生物类别、营养结构、能量循环和物质循环的进化。生态演替(Ecological Succession)是生态进化的基础,它是一短时限的过程,主要有三个方面的内容:(1)它是群落发展有顺序的过程,包括物种组成和群落随时间的改变,有规律地向一定方向发展。(2)它是由群落引起物理环境改变的结果。也就是说,虽然物理环境决定演替类型、变化速度和延续时限,但演替是受群落  相似文献   

3.
刘培生 《化石》1993,(4):2-3
自达尔文与华莱士以来的每位生物学家都承认种间生态学作用对进化的意义。1964年,埃利希和雷文提出了协同进化理论。它反映了生态学相关的不同物种之间的相互作用引起的相互进化。这一理论引起了研究者的广泛重视。近年来,随着进化生态研究的深入发展,学者们对进化过程的生态机制以及生态特性与生态关系进化规律、种间生态学作用引起的物种形成有了进一步的认识。本文仅从协同物种形成的概念出发,对协同物种形成的生态机制以及生物学意义作一简要概述。协同物种形成的概念进化在本质上是一种生态过程,是生物与环境、生物与生物之间相互作用的结果。种群分化的生态机制和物种形成的本质在于对生存条件的逐步适应。按照协同进化理论,物种间的相互作用引起的协同适应  相似文献   

4.
浅谈“进化生态学”   总被引:1,自引:0,他引:1  
进化生态学是一门新兴学科。关于生态学、进化论以及进化生物学的著作汗牛充栋,而关于进化生态学的著作却如凤毛麟角,难以寻觅。为什么?因为进化生态学是结合进化生物学和生态学的边缘学科,前者是研究物种起源、演化的科学,后者是研究生物与环境之间关系的科学;一门...  相似文献   

5.
自1895年E.Warming的《植物生态学》一书的出版,标志着植物生态学萌芽时期的结束。随着20世纪生产的发展和科学新时期的来临,植物生态学在全世界范围内迅速地发展起来,特别是近代,由于数学、物理学和化学纷纷浸透到生态学领域中来,相继形成了数学生态学、生态物理学和化学生态学等等分支学科。我们要讨论的是生态生物化学的一个重要部分,即植物对环境的生物化学适应。生态学与生物化学似乎是截然不同的两个学科,但二者的结合在近年已得到了惊人的成果。为此,本文同时简要介绍1977年英国出版的啥鲍恩(J.B.Harborne)所著的《生态生物化学导论》,因为生态生物化学是近十多年才迅速发展起来的。  相似文献   

6.
现代生态学的中心就是探讨生物有机体在地球上的分布和数量规律,它既具有环境科学的特征,同时又具备进化生物学的特征。近二十年来,生态学中最重要的进展之一当推进化生态学的掘起。因为生物有机体的最基本特征之一就是在同环境的生存斗争中竭尽全力保持种的生存和繁衍,因此生物的适应、进化是生态学研究的核心问题之一。美国著名动物生态学家Paul Colinuaux教授编著的《生态学,(《Ecology》)一书就是以进化生态学为主线的一本优秀的普通生态学教科书,该书内容极为丰富,几乎涉及了现代生态学的所有领域,书中阐述的一些内容,如:生物能量学与生物适应性、生态系统与社会系统,生态系统能量学、  相似文献   

7.
试论达尔文进化论与协同进化论   总被引:11,自引:0,他引:11  
蓝盛芳 《生态科学》1995,(2):167-170
进化在本质上是一种生态过程,达尔文进化论是人类对生物界进化认识的巨大成就,但它不恰当地把生存斗争当作进化的主要动力和普遍的原则,当代基于生态多样性的协同进化论认为生物进化包括相互受益的相互制约机制,优胜劣汰的生存斗争只是制机制中的一种机制,人类必须维护生物多样性和生物圈的协同进化,同自然界和谐、协同发展。  相似文献   

8.
微生态学(microecology)这一术语,是德国学者沃尔克·鲁斯(Volker Rusch)博士于1977年首次提出,并于1985年给“微生态学”下定义为“微生态学是细胞水平或分子水平的生态学”。中国康白教授于1988年在《微生态学》一书中为“微生态学”下定义为“研究正常微生物群与其宿主相互关系的生命科学分支。”微生物与植物的关系,在微生态学中是最典型、最原始和最明显的微生态学关系。  相似文献   

9.
走近达尔文(1)--《物种起源》与达尔文的进化理论   总被引:1,自引:0,他引:1  
李征 《化石》2004,(4):7-8
1859年达尔《物种起源》一书首版面世,首次系统全面地论述了达尔自己的进化论思想,书中引用了很多古生物学、地质学和生物学等方面的证据,详实可信,使科学的进化理论第一次在宗教神学所包围的大的社会环境下旗帜鲜明地被确立下来,不再是以前较软弱、不够完善的理论假说或思想萌芽了。此后,越来越多的人了解、接受了达尔的进化思想,并使之不断发展、完善,产生了系统的进化理论体系——达尔主义。  相似文献   

10.
浅谈"协同进化"   总被引:1,自引:1,他引:0  
陈敏 《生物学通报》2003,38(4):31-31
“协同进化”(Coevolution)一词是 196 4年 Ehrhich和 Raven在《Evolution》(进化 )杂志上正式首次提出 ,用以阐述昆虫与植物 (蝴蝶及其采食植物之间 )进化历程中的相互关系。现已广泛用于描述自然界中相互之间有密切关系的物种 (甚至器官 )的进化模式 ,是进化生物学、系统学、生态学乃至发育生物学等学科的一个研究热点。援引《Biology》(Starr主编 ,1994 ,第 2版 )中的定义 ,协同进化是指自然生境中两个或多个物种 ,由于生态上的密切联系 ,其进化历程相互依赖 ,当一个物种进化时 ,物种间的选择压力发生改变 ,其他物种将发生与之相适应…  相似文献   

11.
Biophysicochemical approaches to the solution of nanotechnology problems associated with the design of functional biomimetic nanosystems, hybrid and composite nanobiomaterials and study of their structure-function relationships. The results of studies concerned with physicochemical mechanisms of the formation of organized biomimetic nanostructures and bioinorganic nanomaterials in systems involving a bulky liquid phase and the interface (gas-liquid, solid-liquid, liquid-liquid)during the synthesis and structure formation with the participation of the components of colloid systems, inorganic nanoparticles of various composition and clusters of metals, surfactants, polyelectrolytes and their complexes are discussed. In the development of the methods for the formation of composite bioinorganic nanosystems containing inorganic nanocomponents, two major approaches were used: adsorption and incorporation into the biomolecular matrix or colloid system of presynthesized inorganic nanoparticles, as well as the synthesis of the inorganic nanophase immediately in the biomolecular system. The methods of obtaining biomaterials and nanosystems are based on the principles of biomimetics, biomineralization, self-assembly and self-organization, combination and integration of a number of synthetic and physicochemical methods (physical and chemical adsorption, Langmuir technique, the formation of polycomplexes, chemical linking, competitive interactions, and substitution of ligands in supramolecular and coordination complexes) and nanocomponents of different nature. In particular, a novel approach to the preparation of highly organized nanofilm materials was developed, which is based on the effect of self-assembly and self-organization of colloid nanoparticles during the formation of their complexes with polyfunctional biogenic ligands in the volume of the liquid phase in the absence of any surfaces and interfaces. The physical and chemical factors responsible for the formation of structurally ordered biomolecular and composite nanosystems including nano-sized components of different nature and the possibilities to control the composition, structure, and properties of resulting nanomaterials and nanosystems are discussed. The experimental methods and approaches developed may be useful in studies of structure-property relationships and basic mechanisms of structural organization and transformation at the nanoscales level in biological, artificial, and hybrid nanosystems. The problems of practical application of the synthetic methods and the corresponding nanomaterials are discussed.  相似文献   

12.
The authors present the results of examination of tremor (hand and trunk) of the amplitude of H- and T-reflexes and of the H-reflex inhibition during the contraction of antagonistic muscles and of facilitattion of T- and H-reflexes during the Yendrassik maneuvre in 33 children with hyperfunction of the thyroid gland and 20 normal subjects. It was established that the amplitude of tremor was greater and the frequency was less in these patients than in normal subjects; the amplitude of the H- and T-reflexes was enhanced, and the intensity of reciprocal inhibition of the soleus muscle motor neurons was less in the patients. Comparison of the amplitude of the T- and H-reflexes indicated that against the background of the Yendrassik maneuvre facilitation of the T-reflex was less intense and facilitation of the H-reflex was more intense than in normal subjects. The authors supposed that the enhanced tremor in the patients was due to the motor neurons pool depolarization, to decrease the efficacy of reciprocal inhibition and to diminished suprasegmental influences spread to the gamma-motor neurons.  相似文献   

13.
为探究低温层积过程中桃儿七种子细胞壁代谢及种皮超微结构与休眠解除的内在联系,该研究通过低温层积解除桃儿七种子休眠,分析休眠解除过程中种子不同部位细胞壁组分及相关代谢酶的变化,同时利用扫描电镜对种皮的超微结构进行观察。结果表明,(1)桃儿七种皮主要由角质层、栅状石细胞层及海绵组织层3层构成,在层积过程中,种皮内部的海绵组织逐步疏松膨胀,种皮表面破损加剧;(2)种子不同部位的细胞壁组分具有明显差异,整个层积过程中,种胚、种皮和胚乳中的纤维素含量均在层积中期(45 d和60 d)降至最低,3个部位的纤维素酶活性在层积中期对应升高;种胚和种皮内的半纤维素含量均在层积中期显著下降,种皮中甘露聚糖酶活性和木糖苷酶活性在层积中期时相应达到最大;3个部位的果胶含量均在层积后期(75 d和90 d)时显著下降,而种皮和胚乳中多聚半乳糖醛缩酶活性也在层积后期相应升高;(3)种胚和胚乳内过氧化物酶活性在层积75 d和90 d时明显下降,而SOD活性在此时显著上升。(4)种子不同部位3种木质素单体的组成比例具有明显区别,同时3种木质素单体含量均随层积时间的延长而显著降低,且胚乳和种皮中的S-木质素含量对种子萌发存在显著的负向影响关系。研究认为,在低温层积过程中,桃儿七种子内细胞壁组分纤维素、半纤维素及木质素的逐步酶解,活性氧作用下的细胞壁松弛以及海绵组织层的疏松膨胀和种皮的破裂,破坏了细胞壁的刚性结构,促使种子机械束缚力降低,吸水性能提高、胚根生长能力增强,最终导致其休眠解除。  相似文献   

14.
The summarized results of original studies, carried out in 1988-2003 by scientists of the Gamaleya Research Institute of Epidemiology and Microbiology, are discussed. The part dealing with the regularity and mechanisms of the circulation of pathogenic bacteria in the biocenosis of soil and water reservoirs includes the following subjects: population and intracellular interactions with protozoa; the evaluation of different representatives of hydrobios as hosts and the transmission along trophic biocenotic chains; the effect of algae and their metabolic products on bacterial populations; the possibility of the colonization of higher plants from the soil and the subsequent infection of rodents; the variability and clonal structure of bacterial population in its interaction with protozoa and plants; the chain of Yersinia circulation in agrocenosis. The part dealing with the mechanisms of the prolonged reservation of causative agents includes such subjects as the reversible transition of bacteria into the latent (uncultivable) state in soils and water reservoirs, as well as the biological inductors of this process; the prolonged preservation of latent bacteria in the cysts of protozoa and blue-green algae; the indication of causative agents in the natural foci of plague and pseudotuberculosis. On the basis of the original investigations and the data of literature new theoretical review in the field of the natural foci and the epidemiology of sapronotic infections have been formulated.  相似文献   

15.
孔令桥  郑华  欧阳志云 《生态学报》2019,39(23):8903-8910
山水林田湖草系统保护与修复的重要目标是维护和提升区域生态系统服务。基于山水林田湖草生命共同体理念,以维护和提升人类福祉所需的重要生态系统服务为目标,提出生态系统服务视角下的山水林田湖草系统治理框架,以实现流域生态系统整体保护、质量提升和格局优化。基于该框架,以洞庭湖流域为例,通过流域生态系统格局、生态系统质量状况分析、流域生态系统服务重要性评估和生态问题识别,构建流域生态安全格局,为实现可持续的山水林田湖草生命共同体提出系统保护与修复布局建议。通过洞庭湖流域的分析案例为流域山水林田湖草生态保护与修复重要区域的识别提供了可借鉴的指标和定量分析方法,为流域尺度构建生态安全格局、实现山水林田湖草系统保护和修复提供思路和途径。  相似文献   

16.
Morita and Perkins' method was applied to the study of the stage of ingestion and destruction of an antigen (sheep erythrocytes) in the macrophages of peritoneal exudate of rabbits and rats and in the microphages of rabbit pleural exudate. Ingestion and intracellular destruction of the antigen were accompanied by intensified respiration and glycolysis of phagocytes. Respiration of the three types of phagocytes at two stages of phagocytosis and also the digestive capacity of microphages proved to be sensitive to cyanide and colchicine. The latter failed to influence the ingestion of the antigen by the three types of phagocytes and its digestion by macrophages. The differences in the metabolism routes of macro- and microphages in intracellular destruction of the antigen was postulated. An intensification of the phagocytic activity after the immunization was characteristic of rabbit and rat macrophages.  相似文献   

17.
化学除草剂对农田生物群落的影响   总被引:39,自引:0,他引:39  
从直接作用和间接作用两个方面,在个体、种群和群落3个水平上综述了化学除草剂对农田植物、动物和微生物群落的影响,并提出了今后需要加强研究的几个问题(1)残留在作物和杂草植株内的除草剂及其代谢产物通过食物链和生物富集作用对农田动物群落各级消费者造成的影响;(2)非作物生境使用化学除草剂对毗邻作物生境天敌群落的影响,以及作物生境使用除草剂对邻近非作物生境天敌群落的影响;(3)由除草剂长期使用引起的杂草群落演替、多样性下降、地表覆盖物和地下生物量减少对土壤动物和微生物群落的物种组成、分布、丰富度及其生态功能的影响;(4)化学除草剂与杀虫剂和化肥等其他农用化学品对农田生物群落的联合作用。  相似文献   

18.
口唇部是主要的面部形态区域之一,具有重要的生理功能。嘴唇保护口腔免受外部物质的渗透,维持口腔内部的湿度和温度,帮助咀嚼,同时也是外科美容整形手术中的主要部位之一,且在法医物证研究中唇纹也具有重要的鉴别价值。目前关于口唇部形态的研究主要包括以下几个方面:口唇部形态变异的性别、年龄、族群差异;影响口唇部形态变异的因素,如遗传基因、饮食结构、牙齿及颌骨形态和呼吸方式等;口唇部形态研究在医学、个人身份识别及法医刑侦领域的相关应用等。国内口唇部形态研究相对较少,尤其缺乏较为系统的口唇部形态生长发育及变异研究。本文通过梳理和归纳国内外相关文献的研究数据和结论,对口唇部形态相关研究作简要概述,并对国内口唇部生长发育及形态变异研究作了简要回顾和展望。  相似文献   

19.
S F Amakiri 《Acta anatomica》1979,103(4):434-444
Various histochemical and histological techniques were used to study the melanin and dopa-positive cell distribution in the skin of some tropical and temperate breeds of cattle in Nigeria. Melanin pigments were concentrated in the basal and lower spinous layers of the epidermis and in the hair cortex, follicle sheaths and papillae of the various breeds. In the White Fulani and N'Dama breeds, melanin pigments were however found in all layers of the epidermis. Dopa-positive cells (melanocytes) were observed in the epidermis, dermis and hair follicles; the distribution pattern varied among breeds, being copiously disposed in the basal epidermis and papillary dermis in the White Fulani and Muturu and, except in areas of thick epidermal ridges, scanty in the epidermis and dermis of the Friesian and N'Dama. Mast cell distribution pattern in the various breeds was similar to that of the dopa-positive cells. Peroxidase-positive cells were present in the basal epidermis and upper dermis of the Muturu, widespread in the subepidermal layer of the N'Dama and very scanty in the dermis of the White Fulani and Friesian. Acid phosphatase activity was intense in the granular layer of the Muturu and N'Dama breeds and also in the papillary dermis and hair follicles, whereas alkaline phosphatase-positive dendritic cells, and 'clear' cells were also observed in the basal and upper epidermis.  相似文献   

20.
Data were obtained on 1039 recoveries of embryos from beef cows of four breeds at two locations, in clinic and on farm. General linear models procedures were utilized to determine the effects of breed, location, age of donor, dosage of follicle stimulating hormone (FSH) and the interaction of age and FSH on the following dependent variables: 1) the mean number of ova (unfertilized oocytes and embryos) recovered; 2) the mean number and percentage of embryos (fertilized; live and dead) recovered; and 3) the mean number and percentage of transferable embryos recovered. The interaction of age of donor and dosage of FSH with breed and location prevented the pooling of data over breed and location. The mean number of ova recovered was affected by age of the donor (Charolais-in clinic), or the interaction between age of donor and dosage of FSH (Polled Hereford-in clinic and -on farm and Simmental -on farm). The mean number of embryos was affected by age of donor (Polled Hereford-in clinic), dosage of FSH (Simmental-in clinic) or their interaction (Angus-on farm). The mean number of transferable embryos was affected by age of donor (Polled Hereford-in clinic and -on farm, Simmental-in clinic and Angus-on farm). General linear models procedures were utilized to determine the effects of the embryo (stage of development and quality) and the recipient (synchrony with the donor) on the rate of pregnancy. Rate of pregnancy varied with embryo quality score and synchrony of the recipient and the embryo. In conclusion, the superovulatory response was found to be highly breed-specific, and most of the variability in embryos produced was attributed to the number of ova recovered. However, the number of ova, embryos and transferable embryos recovered was further influenced by age of the donor, dosage of FSH or their interaction.  相似文献   

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