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1.
In the series of previous publications by the author (2000, 2002, 2005), a genetic model explaining the phenomenon of evolutionary progress was presented. In the present paper, this model is described in general terms. The model is based on views on regular changes of ecological potential of organisms on a macroevolutionary time scale. According to these views, macroevolution has its own pattern, which cannot be seen in the microevolutionary process. Hence, the statement of the synthetic theory of evolution that “macroevolution proceeds via microevolution” is incorrect.  相似文献   

2.
The comparative analysis of scientific heritage of Richard Goldschmidt and Julian Huxley shows convincingly the resemblance of these two scientists' views over the core problems of evolutionary theory, genetics and development biology. They both contributed to developing a triad "genetics--development--evolution". The problem of a relative growth of animals was the central point in both Goldschmidt's and Huxley's works. Huxley developed a formula of the allometric growth (law of constant differential growth) while Goldschmidt was the first to draw up the broad interpretation of the consequences of that phenomenon. Both scientists belonged to initiators of development genetics and used the "non-morganian" genetics in their efforts of solving problems of macroevolution. Goldschmidt tended toward an idea of an important role of macromutation in the process of macroevolution, though Huxley adhered to more moderate views. But at the same time the concept of preadaptive mutations proposed by Huxley was close to Goldschmidt's idea of macromutants. It is shown that both scientists analyzed profoundly the changes in early stages of embryogenesis in respect to macroevolution. It is not likely to be reasonable to oppose firmly Goldschmidt's saltationism to the evolutionary synthesis of Huxley. They developed the larger biological problems in a similar way, and undoubtedly their works in the field helped to enrich the development of the views over genetics and evolution. The open-minded analysis of Goldschmidt's and Huxley's concepts leads to creating modern and up-to-date views over the theory of evolution where seemingly incompatible things go together rather well and supplement each other. Evo-Devo rediscovered Goldshmidt's Biology and Huxley's Synthesis.  相似文献   

3.
The study of biodiversity started as a single unified field that spanned both ecology and evolution and both macro and micro phenomena. But over the 20th century, major trends drove ecology and evolution apart and pushed an emphasis towards the micro perspective in both disciplines. Macroecology and macroevolution re‐emerged as self‐consciously distinct fields in the 1970s and 1980s, but they remain largely separated from each other. Here, we argue that despite the challenges, it is worth working to combine macroecology and macroevolution. We present 25 fundamental questions about biodiversity that are answerable only with a mixture of the views and tools of both macroecology and macroevolution.  相似文献   

4.
Although contemporary high school and college textbooks of biologygenerally cover the principles and data of microevolution (geneticand populational change) and speciation rather well, coverageof what is known of the major changes in evolution (macroevolution),and how the evidence is understood is generally poor to nonexistent.It is critical to improve this because acceptance of evolutionby the American public rests on the understanding of how weknow what we know about the emergence of major new taxonomicgroups, and about their adaptations, behaviors, and ecologiesin geologic time. An efficient approach to this problem is toimprove the illustrations in college textbooks to show the consilienceof different lines of fossil, morphological, and molecular evidencemapped on phylogenies. Such "evograms" will markedly improvetraditional illustrations of phylogenies, "menageries," and"companatomies." If "evograms" are installed at the collegelevel, the basic principles and evidence of macroevolution willbe more likely taught in K-12, thus providing an essential missingpiece in biological education.  相似文献   

5.
Contemporary evolutionary biology comprises a plural landscape of multiple co-existent conceptual frameworks and strenuous voices that disagree on the nature and scope of evolutionary theory. Since the mid-eighties, some of these conceptual frameworks have denounced the ontologies of the Modern Synthesis and of the updated Standard Theory of Evolution as unfinished or even flawed. In this paper, we analyze and compare two of those conceptual frameworks, namely Niles Eldredge’s Hierarchy Theory of Evolution (with its extended ontology of evolutionary entities) and the Extended Evolutionary Synthesis (with its proposal of an extended ontology of evolutionary processes), in an attempt to map some epistemic bridges (e.g. compatible views of causation; niche construction) and some conceptual rifts (e.g. extra-genetic inheritance; different perspectives on macroevolution; contrasting standpoints held in the “externalism–internalism” debate) that exist between them. This paper seeks to encourage theoretical, philosophical and historiographical discussions about pluralism or the possible unification of contemporary evolutionary biology.  相似文献   

6.
Macroevolution, or evolution of superspecies taxa is the process of transformation of “organismal” life flows on the Earth during its geological history. In the present study, this process is analyzed with using the system and evolutionarily?ecological approaches. Based on modern paleontological, evolutionary biological, molecular, and genetic data, mostly on vertebrates and hominins, the major factors and patterns of macroevolution and also the role of macroevolution in the biosphere evolution are discussed. The fundamental bases of the concept of macroevolution, the problems of methodology and methods of the study of organismal evolution are considered. It is shown that the processes at the macroevolutionary level agree with the epigenetic theory of evolution.  相似文献   

7.
In order to broaden the comparative scope of evolutionary developmental biology and to refine our picture of animal macroevolution, it is necessary to establish new model organisms, especially from previously underrepresented groups, like the Lophotrochozoa. We have established the culture and protocols for molecular developmental biology in the rotifer species Brachionus plicatilis Müller (Rotifera, Monogononta). Rotifers are nonsegmented animals with enigmatic basal position within the lophotrochozoans and marked by several evolutionary novelties like the wheel organ (corona), the median eye, and the nonpaired posterior foot. The expression of Bp-Pax-6 is shown using whole-mount in situ hybridization. The inexpensive easy culture and experimental tractability of Brachionus as well as the range of interesting questions to which it holds the key make it a promising addition to the "zoo" of evo-devo model organisms.  相似文献   

8.
Recently, new phylogenetic comparative methods have been proposed to test for the association of biological traits with diversification patterns, with species ecological “niche” being one of the most studied traits. In general, these methods implicitly assume natural selection acting at the species level, thus implying the mechanism of species selection. However, natural selection acting at the organismal level could also influence diversification patterns (i.e., effect macroevolution). Owing to our scarce knowledge on multi-level selection regarding niche as a trait, we propose a conceptual model to discuss and guide the test between species selection and effect macroevolution within a hierarchical framework. We first assume niche as an organismal as well as a species’ trait that interacts with the environment and results in species-level differential fitness. Then, we argue that niche heritability, a requirement for natural selection, can be assessed by its phylogenetic signal. Finally, we propose several predictions that can be tested in the future by disentangling both types of evolutionary processes (species selection or effect macroevolution). Our framework can have important implications for guiding analyses that aim to understand the hierarchical perspective of evolution.  相似文献   

9.
The goal of this research was to illuminate the relationship between students’ acceptance and understanding of macroevolution. Our research questions were: (1) Is there a relationship between knowledge of macroevolution and acceptance of the theory of evolution?; (2) Is there a relationship between the amount of college level biology course work and acceptance of evolutionary theory and knowledge of macroevolution?; and (3) Can college student acceptance of the theory of evolution and knowledge of macroevolution change over the course of a semester? The research participants included 667 students from a first-semester biology course and 74 students from the evolutionary biology course. Data were collected using both the MATE (a measure of the acceptance of evolutionary theory) and the MUM (a measure of understanding of macroevolution). Pre-instruction data were obtained for the introductory biology course, and pre- and post-data were obtained for the evolutionary biology course. Analysis revealed acceptance of evolution (as measured by the MATE) was correlated to understanding of macroevolution, and the number of biology courses was significantly correlated to acceptance and knowledge of macroevolution. Finally, there was a statistically significant change in students’ understanding of macroevolution and acceptance of evolution after the one-semester evolutionary biology course. Significance of these findings is discussed.  相似文献   

10.
Analyses of evolution and maintenance of quantitative genetic variation depend on the mutation models assumed. Currently two polygenic mutation models have been used in theoretical analyses. One is the random walk mutation model and the other is the house-of-cards mutation model. Although in the short term the two models give similar results for the evolution of neutral genetic variation within and between populations, the predictions of the changes of the variation are qualitatively different in the long term. In this paper a more general mutation model, called the regression mutation model, is proposed to bridge the gap of the two models. The model regards the regression coefficient, γ, of the effect of an allele after mutation on the effect of the allele before mutation as a parameter. When γ = 1 or 0, the model becomes the random walk model or the house-of-cards model, respectively. The additive genetic variances within and between populations are formulated for this mutation model, and some insights are gained by looking at the changes of the genetic variances as γ changes. The effects of γ on the statistical test of selection for quantitative characters during macroevolution are also discussed. The results suggest that the random walk mutation model should not be interpreted as a null hypothesis of neutrality for testing against alternative hypotheses of selection during macroevolution because it can potentially allocate too much variation for the change of population means under neutrality.  相似文献   

11.
A high molecular mass complex of aminoacyl-tRNA synthetases is readily isolated from a variety of eukaryotes. Although its composition is well characterized, knowledge of its structure and organization is still quite limited. This study uses antibodies directed against prolyl-tRNA synthetase for immunoelectron microscopic localization of the bifunctional glutamyl-/prolyl-tRNA synthetase. This is the first visualization of a specific site within the multisynthetase complex. Images of immunocomplexes are presented in the characteristic views of negatively stained multisynthetase complex from rabbit reticulocytes. As described in terms of a three domain working model of the structure, in "front" views of the particle and "intermediate" views, the primary antibody binding site is near the intersection between the "base" and one "arm." In "side" views, where the particle is rotated about its long axis, the binding site is near the midpoint. "Top" and "bottom" views, which appear as square projections, are also consistent with the central location of the binding site. These data place the glutamyl-/prolyl-tRNA synthetase polypeptide in a defined area of the particle, which encompasses portions of two domains, yet is consistent with the previous structural model.  相似文献   

12.
Two sets of evolutionary phenomena find no explanation through current theory. For the static phenomena (such as homology, homonomy, systematic weight, and "Type") there is no causal base, although these principles are responsible for all phenomena of predictable order in the living world. The dynamic phenomena (such as homodynamy, coadaptation, parallel evolution, orthogenesis, Cartesian transformation, typostrophy, hetermorphosis, systemic mutation, and spontaneous atavism) have no causal explanation, although they are responsible for all directed phenomena in macroevolution. These phenomena share one unifying principle which can be explained by a system theory of evolution based on, but extending, the current synthetic theory. This system theory envisages feedback conditions between genotype and phenotype by which the chances of successful adaptation increase if the genetic units, by insertion of superimposed genes, copy the functional dependencies of those phene structures for which they code. This positive feedback of the adaptive speed (or probability) within a single adaptive direction is compensated by negative feedback in most of the alternative directions. The negative feedback operates as selection not be environmental but by systemic conditions developed by the organization of the organism. The consequences are an imitatively organized system of gene interractions, the rehabilitation of classical systematics, the reality of the "natural system," and, in general, the resolution of the contradiction between neodarwinists and their critics, between reductionists and holists, between "a priori" and "a posteriori" views, between idealism and materialism, and between the notions of freedom and of purpose in evolution.  相似文献   

13.
Species interactions lie at the heart of many theories of macroevolution, from adaptive radiation to the Red Queen. Although some theories describe the imprint that interactions will have over long timescales, we are still missing a comprehensive understanding of the effects of interactions on macroevolution. Current research shows strong evidence for the impact of interactions on macroevolutionary patterns of trait evolution and diversification, yet many macroevolutionary studies have only a tenuous relationship to ecological studies of interactions over shorter timescales. We review current research in this area, highlighting approaches that explicitly model species interactions and connect them to broad‐scale macroevolutionary patterns. We also suggest that progress has been made by taking an integrative interdisciplinary look at individual clades. We focus on African cichlids as a case study of how this approach can be fruitful. Overall, although the evidence for species interactions shaping macroevolution is strong, further work using integrative and model‐based approaches is needed to spur progress towards understanding the complex dynamics that structure communities over time and space.  相似文献   

14.
N N Vorontsov 《Genetika》1988,24(6):1081-1088
A brief survey of the development of concepts on the role of macromutations in evolution is given. Contrary to Iu. A. Filipchenko (1926, 1927), who introduced the "micro- and macromutation" terms and believed that regularities of macroevolution could not be reduced to microevolutionary processes, the majority of "synthetists" explained any form of evolution by changes in allele frequencies. From the studies of Drosophila homoeotic mutants R. Goldschmidt (1940) developed the concept of "hopeful monsters" and their role in macroevolution. However, the homoeotic mutants are of drastically reduced viability, which allows the gradualists to reject Goldschmidt's ideas. The distribution of hairlessness mutations (hairless, nude etc.) with the monogenic pattern of inheritance in mammals was studied. Hairless mutants are known in Peromyscus, Mus musculus, Rattus rattus, R. norvegicus, Canis familiaris, Ovis aries. Hairlessness as norm is found in 53 among contemporaneous 1037 mammalian genera. Part of these cases (hairlessness in all Cetacea and Sirenia) may be explained in terms of both macromutations and obligatory gradualism. There is no doubt as to the macromutational origin of hairlessness in the bat Cheiromeles and the rodent Heterocephalus (Bathyergidae); the genera systematically and ecologically close to these have normal pelage. It is quite possible that hairlessness of walrus (Odobenus) has the same origin. The appearance and fixation of single Goldschmidt's macromutation cannot yet be considered as a macroevolutionary process, though the possibility of fixation of a macromutation in nature as a species and genus character contradicts strongly the concept of obligatory gradualism of evolution.  相似文献   

15.
Macroevolution is more than repeated rounds of microevolution   总被引:1,自引:0,他引:1  
SUMMARY Arguments over macroevolution versus microevolution have waxed and waned through most of the twentieth century. Initially, paleontologists and other evolutionary biologists advanced a variety of non-Darwinian evolutionary processes as explanations for patterns found in the fossil record, emphasizing macroevolution as a source of morphologic novelty. Later, paleontologists, from Simpson to Gould, Stanley, and others, accepted the primacy of natural selection but argued that rapid speciation produced a discontinuity between micro- and macroevolution. This second phase emphasizes the sorting of innovations between species. Other discontinuities appear in the persistence of trends (differential success of species within clades), including species sorting, in the differential success between clades and in the origination and establishment of evolutionary novelties. These discontinuities impose a hierarchical structure to evolution and discredit any smooth extrapolation from allelic substitution to large-scale evolutionary patterns. Recent developments in comparative developmental biology suggest a need to reconsider the possibility that some macroevolutionary discontinuites may be associated with the origination of evolutionary innovation. The attractiveness of macroevolution reflects the exhaustive documentation of large-scale patterns which reveal a richness to evolution unexplained by microevolution. If the goal of evolutionary biology is to understand the history of life, rather than simply document experimental analysis of evolution, studies from paleontology, phylogenetics, developmental biology, and other fields demand the deeper view provided by macroevolution.  相似文献   

16.
17.

Background

This article deals with the theoretical size distribution (of number of sub-taxa) of a fossil taxon arising from a simple null model of macroevolution.

Model

New species arise through speciations occurring independently and at random at a fixed probability rate, while extinctions either occur independently and at random (background extinctions) or cataclysmically. In addition new genera are assumed to arise through speciations of a very radical nature, again assumed to occur independently and at random at a fixed probability rate.

Conclusion

The size distributions of the pioneering genus (following a cataclysm) and of derived genera are determined. Also the distribution of the number of genera is considered along with a comparison of the probability of a monospecific genus with that of a monogeneric family.  相似文献   

18.
The initial event in plant floral organogenesis is bract specification, followed by floral meristem (FM) initiation in bract axils, but initiation signals and the interplay between both lateral organs remain unelucidated. Floral organs are initiated on the flanks of the outgrowing FM and the enormous diversity in floral morphology throughout the plant kingdom reflects variations in organ position, meristy and ontogeny. Classical models of floral development have focused on Arabidopsis, which has mostly actinomorphic flowers, and Antirrhinum, which exhibits zygomorphy, although neither species is typical or representative of angiosperm flower diversity. Although the ABCE model defines a centripetal model of organ identity establishment in different whorls, the characterization of floral organ initiation in many species has relied on their morphological appearance, due to a lack of founder cell-specific markers. Recent progress in early Arabidopsis floral development using histology, molecular markers and mutants has led to refinements of existing floral organ initiation paradigms. In Arabidopsis, sepals initiate unidirectionally, in a temporal window characterized by the absence of CLAVATA3 and WUSCHEL stem cell markers and are partly dependent on PRESSED FLOWER function, whereas initiation of inner-whorl organs occurs centripetally. Arabidopsis mutants reveal that the FM is highly polarized along an ab-/adaxial axis and a comparison of floral development in Arabidopsis and Antirrhinum suggests that heterochrony of conserved gene functions has been evolutionarily adaptive.

This review discusses current views on FM and organ specification signals, the gene regulatory networks that underlie floral meristem polarity, and analogies between the development of floral and leaf primordia as lateral organs. Alternative stem-cell proliferation mechanisms and the bifurcation of founder cell populations can help to explain the diversity in floral diversity throughout the plant kingdom and underpin comparative evolutionary biology and macroevolution. An analysis of plants with divergent body plans at the level of organ specification is urgently needed.  相似文献   


19.
A new evolutionary model for diversification in plasmid incompatibility groups (plasmid speciation) is suggested. The model is based on the formation of plasmid cointegrates from two compatible plasmids. The existence of plasmid cointegrates is well known, however, their potential key role in plasmid macroevolution has not yet been recognized. In a hypothesis presented here, one of the rep genes is supposed to be relaxed from selection in plasmid cointegrates and thus becomes free to accumulate mutations. These mutations can lead to a change in incompatibility specificity. Evidence supporting this hypothesis comes from the common occurrence of multi-replicon plasmids in nature as well as from experimental studies on plasmid cointegrate formation. A more speculative extension of this model hypothesizes an evolutionary scenario for origin of the eubacterial single-replicon genome and the eukaryotic multi-replicon genome, as well as the place of plasmids and viruses in this picture.  相似文献   

20.
It is a basis of darwinian evolution that the microevolutionary mechanisms that can be studied in the present are sufficient to account for macroevolution. However, this idea needs to be tested explicitly, as highlighted here by the example of the superceding of dinosaurs and pterosaurs by birds and placental mammals that occurred near the Cretaceous/Tertiary boundary approximately 65 million years ago. A major problem for testing the sufficiency of microevolutionary processes is that independent ideas (such as the existence of an extraterrestrial impact, and the extinction of dinosaurs) were linked without the evidence for each idea being evaluated separately. Here, we suggest and discuss five testable models for the times and divergences of modern mammals and birds. Determination of the model that best represents these events will enable the role of microevolutionary mechanisms to be evaluated. The question of the sufficiency of microevolutionary processes for macroevolution is solvable, and available evidence supports an important role for biological processes in the initial decline of dinosaurs and pterosaurs.  相似文献   

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