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1.
达尔文进化论强调了"物竞天择,适者生存"的理念与逻辑,对动物起源与进化提供了重要解释;然而,为什么会有动物、以及为什么会进化出人类等问题,却仍无答案。在我们实验室近年来从事肥胖及相关慢病研究中发现"饥饿源于菌群"并发展出可通过控制肠道菌群向人体传递的饥饿感的生物技术之后,提出科学假说认为,和人类同样具有消化道结构的动物,很有可能也是受到肠道菌群摄食的胁迫压力而进化的,即动物和人体的消化道以"中空"的拓扑学结构为基础,形成可容纳与相应动物种类相适应的肠道菌群微生态系统。这些肠道菌群终生共生于肠道,通过向动物传递饥饿感而迫使动物摄食而生存,同时肠道菌群也通过动物摄食的营养物质繁殖自己的后代,从而提出了以肠道菌群为中心、动物受肠道菌群胁迫而协同进化的"菌心进化论",是对"宿主进化论"的重要补充和完善,有利于我们从新的角度来理解和诠释动物的起源、进化和发展过程,乃至促进我们逐渐理解自然界从动物进化到人类之后,有可能是在实现从菌群主导的以食物为代表的"物质需求"向人类智慧主导的"精神需求"的新跃迁。  相似文献   

2.
《生理通讯》2009,28(2)
英国杰出的生物学家、进化论的主要奠基人达尔文诞辰200周年前夕,复旦大学生命科学院教授钟扬表示,现代分子生物学正从分子进化的角度提供支持进化论的论据,同时也在推动进化论理论进一步完善。  相似文献   

3.
奇云 《生命世界》2006,(3):58-63
尽管美国是科技最发达的国家之一,但多数公众仍不接受达尔文的进化论。美国哥伦比亚广播公司2005年10月的民意测验显示,51%的美国人相信人是上帝制造的,30%的人认为上帝参与了人的进化。面对进化论反对者的不断挑战,捍卫进化论的科学家们做了些什么呢?  相似文献   

4.
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   

5.
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   

6.
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   

7.
达尔文-科学进化论的奠基者   总被引:1,自引:0,他引:1       下载免费PDF全文
梁前进  邴杰  张根发 《遗传》2009,31(12):1171-1176
2009年, 时逢英国博物学家查尔斯·罗伯特·达尔文(Charles Robert Darwin,1809-1882)诞辰200周年, 进化论光辉著作《物种起源》发表150周年。历史的发展不断认证达尔文的《物种起源》一书是生物学史上不朽的经典著作, 如今《物种起源》所提及的许多观点已成为人尽皆知的常识, 并且还在不断地发展、完善, 为人类认识自然和自身发展指点方向。文章追忆了先贤的卓越科学贡献和科学探索精神, 并对百年来科学进步和进化论的发展重要成果进行了简要的评述, 指出了进化论未来研究的重点问题。  相似文献   

8.
马纲 《生物学通报》1995,30(5):18-19
动物界具有共同的祖先,由于环境条件的变动,引起动物适应性变动或迁移到别的地方以利生存,出现了动物的多样化。因此,动物的进化经历了由低级向高级,由简单向复杂的发展过程,通过对动物进化论中几个相关概念的辨析,讨论了不同等级动物类群之间的相互关系。  相似文献   

9.
达尔文进化论的挑战分子进化的中性学说   总被引:2,自引:0,他引:2  
十九世纪中叶以前,弥漫在科学界上空的是特创论和物种不变论,首先打破这种阴霾空气的伟人当推英国生物学家达尔文。达尔文经过历时四载的航海考察,于1859年发表了创世之作《物种起源》,其核心进化论对科学界影响之巨大,被革命导师恩格斯将其与能量守恒定律和细胞学说一起,赞誉为十九世纪自然科学的三大发现。进化论在经过一个多世纪的风风雨雨之后,除被不断的补充、修正与完善之外,也遇到过强有力的挑战。本文在对达尔文主义和新达尔文主义作简短回顾的基础上,着重介绍非达尔文主义——分子进化的中性学说的形成、特点及对学术界的影响。  相似文献   

10.
王一 《化石》2005,(2):40-40
生物进化论是生命科学中的哲学,它以各个具体的生命学科的研究成果为基础,从中总结、概括而来;同时,它又从更高的角度指导着生命科学的发展。  相似文献   

11.
The cybernetic definition of a living individual proposed previously (Korzeniewski, 2001) is very abstract and therefore describes the essence of life in a very formal and general way. In the present article this definition is reformulated in order to determine clearly the relation between life in general and a living individual in particular, and it is further explained and defended. Next, the cybernetic definition of a living individual is confronted with the real world. It is demonstrated that numerous restrictions imposed on the cybernetic definition of life by physical reality imply a number of particular properties of life that characterize present life on Earth, namely: (1) a living individual must be a dissipative structure (and therefore a low-entropy thermodynamic system out of the state of equilibrium); (2) spontaneously-originated life must be based on organic compounds; (3) evolutionarily stable self-dependent, free-living individuals must have some minimal level of complexity of structure and function; (4) a living individual must have a record of identity separated from an executive machinery; (5) the identity of living individuals must mutate and may evolve; (6) living individuals may collect and accumulate information in subsequent generations over very long periods of time; (7) the degree of complexity of a living individual reflects the degree of complexity of its environment (ecological niche) and (8) living individuals are capable of supple adaptation to varying environmental conditions. Thus, the cybernetic definition of a living individual, when confronted with the real physical world, generates most of the general properties of the present life on Earth.  相似文献   

12.
The aim of this work was to prove if a Bordetella bronchiseptica living vaccine is able to induce humoral and local antibodies in pigs. The living vaccine was compared with a killed Bordetella bronchiseptica adjuvans vaccine. The results show that piglets of sows vaccinated parenterally with living vaccine and killed adjuvans vaccine develop a stronger humoral immune reaction than piglets vaccinated locally with living vaccine. Sows immunized parenterally with living vaccine permint their piglets in the first three weeks colostral antibodies like sows immunized with killed adjuvans vaccine. The living vaccine induces especially local antibodies.  相似文献   

13.
This paper formulates some taboos relating to living systems and cognition of these systems: in nature, there exist no two identical living complex multicellular organisms; there is no way to create an exact copy of a multicellular organism; there is no way to obtain two identical clones of a unicellular organism if they contain a sufficiently large number of cells; based on comparing present-day organisms, it is impossible to restore the structure of the first living cell and the processes that have led to its emergence; it is impossible to create a living cell from its separate simple constituents; the mechanisms determining cell vitality are essentially incognizable.  相似文献   

14.
Based on fieldwork among the Sa'dan Toraja of Indonesia, this article examines a specific relationship between the living and the dead. It is a relationship which is usually described in terms of intimacy. Within this intimacy, the living and the dead are described as sharing the same desires. Furthermore, as far as the living are concerned, these desires have to be expressed in words and acted out in the form of mortuary sacrifices. In this way, the living are said to remember the dead. My discussion focuses on the implications of this memory.  相似文献   

15.
Bionics, Biological Systems and the Principle of Optimal Design   总被引:1,自引:0,他引:1  
The living world is an exciting and inexhaustible source of high performance solutions to the multitude of biological problems, which were attained as a result of a natural selection, during the millions and millions years evolution of life on Earth. This work presents and comments some examples of high performances of living beings, in the light of the universal principle governing the realm of living matter: Optimal Design Principle. At the same time, the transfer of these optimal solutions, from living matter to the technologies, is also discussed. This transfer is offering new and fertile perspectives to future technologies, which must be more efficient, cheaper and in perfect harmony with the biosphere.  相似文献   

16.
Squatter dwellers are found in almost all the Third World countries. Poor living conditions are the characteristic features of all the squatter settlements. Again, poor living conditions are also associated with the health condition of the squatter dwellers. In the present study an attempt has been made to compare and contrast the living condition of two social groups (Hindu and Muslim) inhabiting a squatter settlement in Calcutta, India. The results show that the overall living condition of the Muslim is worse than that of the Hindu. The morbidity pattern is also worse in the Muslim than in the Hindu.  相似文献   

17.
应用计算机辅助形态测量系统,对我国青海高原贵南县(海拔3100m)、玛多县(海拔4300m)6-7岁小儿红细胞形态进行了定量分析。与北京市儿童(平原地区)相比,高原正常儿童细胞平均周长、面积、直径较平原对照组大,而红细胞平均厚度减小(P<0.01)。且红细胞平均周长、面积、直径与海拔高度呈正相关。红细胞平均厚度与海拔高度呈负相关(P<0.0001)。在高原低氧状态下,红细胞形态的这种改变使红细胞比表面代偿性增加,这将更利于红细胞与周围的气体交换。红细胞形态的这种适应性改变具有重要的生理学意义。  相似文献   

18.
Assemblages of living benthic invertebrates (predominantly bivalve molluscs) from the sand-channel habitat of two Southern California (U.S.A.) lagoons were sampled on ten occasions over a 37-month period. A one-time sampling of the corresponding assemblages of accumulating dead remains made possible a contrast of living and dead assemblages designed to assess the biasing effects of post-mortem transportation, shell dissolution, and time-averaging. Species-by-species comparisons of the living and dead molluscs found together in the same samples strongly suggested that post-mortem transportation is insignificant within this high-energy habitat. A similar conclusion arose from contrasting the pattern of spatial heterogeneity of the living community with that of the dead assemblage. Species presence-and-absence comparisons were generally more reliable than comparisons of relative abundances. Adjustments for experimentally determined rates of post-mortem shell dissolution proved significant and further decreased the correspondence in relative abundances between living and dead assemblages. Greater temporal variability of living populations at Mugu Lagoon, probably caused by a more harsh physical environment, increased the differences in composition between living and dead assemblages, which suggests that correspondence in relative abundances between living and dead assemblages generally should be expected to decrease as the life environment becomes more harsh.  相似文献   

19.
Small-scale group living for elderly with dementia: a clarification This article discusses the results of a Concept Mapping, held to clarify the concept of small-scale group living for elderly with dementia. Seventeen experts from different backgrounds formulated 91 statements about small-scale group living. These were subsequently depicted on a concept map with two dimensions: care versus living and individual versus context. The statements were then divided into six clusters by hierarchical clusteranalysis. Five of these clusters centred around the arrangements of the individual lives of the residents and the collective lives of residents and staff, while only one held statements about the physical characteristics of small-scale group living. Therefore, it can be concluded from this Concept Map that small-scale group living is not so much determined by the physical characteristics but by the organisational features of the care context.  相似文献   

20.
Dutch GP's (General Practitioners) take care of people living in homes for the elderly. The population of these homes is selected on the basis of poor functioning on ADL (activities of daily living). We expected to find a group of elderly people within these homes that need more complex primary care. We describe the characteristics of care for an institutionalized elderly population and compare these to the care provided to their independently living peers. The design of this study is a matched case-control study in a Dutch General Practice in the study period 1/1/1998 to 1/7/2004. Our main results show that the rate of cognitive problems is two times, the prevalence of depression even three times higher in older people living in a home for the elderly than in those who live independently. Locomotory problems are a frequent problem in homes for the elderly. Rates of chronic pulmonary problems, atherosclerosis-related diseases and urinary tract infection are higher, whereas no significant differences for CVA, diabetes and cancer were found. Institutionalized older patients use more different types of medication. GP's do not have more contacts with people living in a home for the elderly than with older people living independently. We conclude that people living in homes for the elderly have complex problems, and need special attention for their specific vulnerability. Differences in care are not primarily explained by chronic disease but by problems with mobility, confusion, depression and cognition.  相似文献   

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