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1.
It has been repeatedly claimed that morphological novelties are an unresolved problem in evolutionary theory. Several definitions of novelty exist but most emphasize that novelties imply qualitative changes on the phenotype and not the quantitative gradual changes favored in the neo-Darwinian approach to evolutionary theory. This article discusses how the concept of novelty is used to describe aspects of morphological evolution that are not satisfactorily explained under the modern synthesis. In this article, it is suggested that there is a repertoire of morphological changes rather than two discrete qualitatively different types of morphological change. How these different types of morphological changes can be understood from the diversity of developmental mechanisms existing in animal development is explored. Specifically, it is proposed that animal morphology and its variation can be understood from the spatial patterns produced by a set of basic developmental mechanisms and their combination. Some specific examples of these kinds of morphologic changes are explained.  相似文献   

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Summary The critical theory of evolution was developed by a group of scientists working together with Wolfgang F. Gutmann at the Senckenberg-Research-Institute in Frankfurt am Main. Gutmann worked at Senckenberg for 37 years. In this time he presented 247 contributions which are distributed over 47 periodicals and books. The ideas that were developed by Gutmann and his colleagues were innovative and pathbreaking for morphology and evolutionary biology. The large number of his morphological publications is indicative of the wide field that was opened up by the concepts of constructional morphology. As some of his colleagues have suggested, constructional morphology as an engineering approach to the study of organisms (i. e., engineering morphology) may replace the traditional concepts of morphology and anatomy and provides the observational base for the historical reconstruction of evolutionary pathways. Constructional morphology as a quasi-engineering approach can be the morphological pendant to the contemporary molecular approaches to biology, as it can provide the necessary morphological basis for the interpretation of the results of molecular studies in the light of evolution.  相似文献   

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Ethology is rooted in the idea that behavior is composed of discrete units and sub-units that can be compared among taxa in a phylogenetic framework. This means that behavior, like morphology and genes, is inherently modular. Yet, the concept of modularity is not well integrated into how we envision the behavioral components of phenotype. Understanding ethological modularity, and its implications for animal phenotype organization and evolution, requires that we construct interpretive schemes that permit us to examine it. In this study, I describe the structure and composition of a complex part of the behavioral phenotype of Parotia lawesii Ramsay, 1885--a bird of paradise (Aves: Paradisaeidae) from the forests of eastern New Guinea. I use archived voucher video clips, photographic ethograms, and phenotype ontology diagrams to describe the modular units comprising courtship at various levels of integration. Results show P. lawesii to have 15 courtship and mating behaviors (11 males, 4 females) hierarchically arranged within a complex seven-level structure. At the finest level examined, male displays are comprised of 49 modular sub-units (elements) differentially employed to form more complex modular units (phases and versions) at higher-levels of integration. With its emphasis on hierarchical modularity, this study provides an important conceptual framework for understanding courtship-related phenotypic complexity and provides a solid basis for comparative study of the genus Parotia.  相似文献   

7.
Systematics,morphology and biological control   总被引:2,自引:0,他引:2  
Accurate systematics is the foundation on which all meaningful research in biology is based. The importance of sound systematics to practical biological control is illustrated by results from several projects on biological control of coccid pests. Correct identification of the pest species or their natural enemies, and recognition of cryptic species or infraspecific entities, have been of utmost importance to the success of many projects. Accurate morphology is the basis of reliable systematics. Unfortunately, basic morphology of the parasitic Hymenoptera is still imperfectly understood and that which is known often is inadequately used. The scanning electron microscope is a valuable tool for comparative morphological research that will go far toward solving these problems. The taxonomic validity of morphological characters, and the extent of intraspecific variation, should be determined by a detailed biometrical study of large series of cultured specimens whenever possible. This approach is illustrated with results obtained in our recent revision of the species ofAphytis, important parasites of diaspine scale insects. Comparative morphology of developmental stages of parasitic Hymenoptera is recognized as an important approach to the study of cryptic species needing much more emphasis.  相似文献   

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By sharing geographic space, species are forced to interact with one another and the contribution of this process to evolutionary and ecological patterns of individual species is not fully understood. At the same time, species turnover makes that species composition varies from one area to another, so the analysis of biological interaction cannot be uncoupled from the spatial context. This is particularly important for clades that show high degree of specialization such as hummingbirds, where any variation in biotic pressures might lead to changes in morphology. Here, we describe the influence of biological interactions on the morphology of Hylocharis leucotis by simultaneously considering potential competition and diet resources. We characterized the extent of local potential competition and local available floral resources by correlating two measurements of hummingbird diversity, floral resources and the size of morphological space of H. leucotis along its geographic distribution. We found that H. leucotis shows an important morphological variability across its range and two groups can be recognized. Surprisingly, morphological variation is not always linked to local hummingbird richness or the phylogenetic similarity of. Only in the southern part of its distribution, H. leucotis is morphologically more variable in those communities where it coexist with closely related hummingbird species. We also found that morphological variation in H. leucotis is independent from the availability of floral resources. Our results suggest that abiotic factors might be responsible for morphological differences across populations in Hylocharis leucotis being biological interactions of minor importance.  相似文献   

9.
Demuth JP  Naidu A  Mydlarz LD 《PloS one》2012,7(1):e28690
While parasites and immunity are widely believed to play important roles in the evolution of male ornaments, their potential influence on systems where male weaponry is the object of sexual selection is poorly understood. We experimentally infect larval broad-horned flour beetles with a tapeworm and study the consequent effects on: 1) adult male morphology 2) male-male contests for mating opportunities, and 3) induction of the innate immune system. We find that infection significantly reduces adult male size in ways that are expected to reduce mating opportunities in nature. The sum of our morphological, competition, and immunological data indicate that during a life history stage where no new resources are acquired, males allocate their finite resources in a way that increases future mating potential.  相似文献   

10.
Actinomycetes, a class of filamentous bacteria, are an important source of several industrially relevant secondary metabolites. Several environmental factors including the media composition affect both biomass growth and product formation. Likewise, several studies have shown that environmental factors cause changes in cellular morphology. However, the relationship between morphology and product formation is not well understood. In this study, we first characterized the effect of varying concentrations of phosphate and ammonia in defined media on pellet morphology for an actinomycete Amycolatopsis balhimycina DSM 5908, which produces balhimycin, a glycopeptide antibiotic. Our results show that higher balhimycin productivity is correlated with the following morphological features: (1) higher pellet fraction in the biomass, (2) small elongated pellets, and (3) shorter filaments in hyphal growth in the periphery of the pellets. The correlation between morphology and product formation was also observed in industrially relevant complex media. Although balhimycin production starts after 72 h with maximum production around 168 h, the morphological changes in pellets are observed as early as 24 h after commencing of the batch. Therefore, morphology may be used as an early predictor of the end-of-batch productivity. We argue that a similar strategy can be developed for other strains where morphological indicators may be used as a batch monitoring tool.  相似文献   

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This paper examines the relationships betweenGoethe's morphology and his ideas on aestheticappraisal. Goethe's science of morphology was toprovide the method for making evident purephenomena [Urphänomene], for makingintuitable the necessary laws behind theperceptible forms and formation of livingnature, through a disciplined perception. Thisemphasis contrasted with contemporary studiesof generation, which focused upon hiddenformative processes. It was his views onaesthetic appraisal that informed theseepistemological precepts of his science. Hisstudy of antique artefacts convinced Goethethat these should be prototypes for all art,since they made perceptible the ideal of art,its archetypes or objective forms. His ambitionwas to eliminate the subjective elements hecontended were leading contemporary art astray.He argued that the techniques he developed forcultivating the perception of the idealexemplars of art could become a model forscience, enabling the intuition of theobjective forms of nature through a similardisciplined and cultivated perception. Thispaper also examines some of the widermotivations for the particular emphases Goethegave to his science and aesthetics, noting asimilar impulse to discipline unruly forces inhis life – in his work as an administrator forthe Weimar court and Jena University, in hisvision of an ideal German culture centred onthe aristocracy, and in his literaryproductions and biographical writings. Finallyit discusses the extent to which those unrulyelements nevertheless remained a potent anddisturbing presence in his understanding ofnature, his art and his life.  相似文献   

12.
植物种群生态学中的构件理论   总被引:59,自引:0,他引:59  
植物种群生态学中的构件理论黎云祥,刘玉成,钟章成(四川师范学院生物系,南充637002)(西南师范大学生物系,重庆630715)ModularTheoryinPlantPopulationEcology.¥LiYunxiang;LiuYucheng(...  相似文献   

13.
《Journal of morphology》2017,278(3):403-417
Anurans exhibit a particularly wide range of locomotor modes that result in wide variations in their skeletal structure. This article investigates the possible correlation between morphological aspects of the hylid postcranial skeleton and their different locomotor modes and habitat use. To do so, we analyzed 18 morphometric postcranial variables in 19 different anuran species representative of a variety of locomotor modes (jumper, hopper, walker, and swimmer) and habitat uses (arboreal, bush, terrestrial, and aquatic). Our results show that the evolution of the postcranial hylid skeleton cannot be explained by one single model, as for example, the girdles suggest modular evolution while the vertebral column suggests other evolutionary modules. In conjunction with data from several other studies, we were able to show a relationship between hylid morphology and habitat use; offering further evidence that the jumper/swimmer and walker/hopper locomotor modes exhibit quite similar morphological architecture. This allowed us to infer that new locomotor modalities are, in fact, generated along a morphological continuum. J. Morphol. 278:403–417, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   

14.
Development and evolution of animal behaviour and morphology are frequently addressed independently, as reflected in the dichotomy of disciplines dedicated to their study distinguishing object of study (morphology versus behaviour) and perspective (ultimate versus proximate). Although traits are known to develop and evolve semi-independently, they are matched together in development and evolution to produce a unique functional phenotype. Here I highlight similarities shared by both traits, such as the decisive role played by the environment for their ontogeny. Considering the widespread developmental and functional entanglement between both traits, many cases of adaptive evolution are better understood when proximate and ultimate explanations are integrated. A field integrating these perspectives is evolutionary developmental biology (evo-devo), which studies the developmental basis of phenotypic diversity. Ultimate aspects in evo-devo studies--which have mostly focused on morphological traits--could become more apparent when behaviour, 'the integrator of form and function', is integrated into the same framework of analysis. Integrating a trait such as behaviour at a different level in the biological hierarchy will help to better understand not only how behavioural diversity is produced, but also how levels are connected to produce functional phenotypes and how these evolve. A possible framework to accommodate and compare form and function at different levels of the biological hierarchy is outlined. At the end, some methodological issues are discussed.  相似文献   

15.
Glioblastoma Multiforme (GBM) is the most malignant brain tumor in adults, highly infiltrative and difficult to cure. According to the histopathological evidence, the glioma cells are found to infiltrate into the surround normal brain tissue, along the Scherer’s structure (e.g. white matter tract and microvasculature). As a major invasion route of microenvironments, these pre-existing anatomic structures should be considered in studying infiltrative movement of glioblastoma. In our previous work, we introduced in vitro biomimetic platform as alternative model of brain-anatomical structures to study about migratory phenotypes of glioblastoma. By applying this proper biomimetic platform, we further investigated the influence of integrin, which is one of mechanoreceptors to sense mechanical cues, on phenotype of glioblastoma cells in this study. On in vitro biomimetic platform, glioblastoma cells show elongated morphology with highly aligned along the patterned direction, which is similar to that on in vivo condition. These morphological changes were gradually progressed in time-dependent manner, which might be mediated by a representative mechanoreceptor, integrin. Treatment of cell adhesive motif for integrin inhibition hinders the morphological dynamics on in vitro biomimetic platform in early time-point compared with cell proliferation cycle. Since cell adhesion mediated by mechanoreceptors is one of essential steps in migration/invasion, our results imply that effect of integrin on glioblastoma invasion is mediated by the mechanosensing process on topography and indicated by morphological changes. For further application, this quantitative analysis of glioblastoma morphology on biomimetic platform can be contributed to simple and ease investigation and effective anti-cancer drug screening.  相似文献   

16.
Plants respond to local heterogeneity in abiotic and biotic conditions by changing module-level morphology, growth, and reproductive patterns. This paper presents a conceptual framework for the study of modular responses in plant crowns, clarifies the points that should be considered for scaling up from modular responses to the consequences at the whole-plant level, characterizes the interspecific differences in modular response patterns, and discusses their ecological significance. The modular response was defined as either autonomous or interactive, depending on whether the response of a module to its local condition is independent from the conditions of other modules. For evaluation of the autonomy of the modular response, the importance of considering positional relationships and organizational levels of modules was then proposed as these internally affect the modular response pattern, and their interspecific differences were characterized using several concepts. The identification of an autonomous modular unit is essential for scaling up module-level studies to the whole plant. For understanding the ecological significance of the modular response, further interspecific comparisons and assessments of the scale and the predictability of environmental heterogeneity are required. The conceptual framework will be useful for such purposes.  相似文献   

17.
Complex networks of species interactions might be determined by species traits but also by simple chance meetings governed by species abundances. Although the idea that species traits structure mutualistic networks is appealing, most studies have found abundance to be a major structuring mechanism underlying interaction frequencies. With a well‐resolved plant–hummingbird interaction network from the Neotropical savanna in Brazil, we asked whether species morphology, phenology, nectar availability and habitat occupancy and/or abundance best predicted the frequency of interactions. For this, we constructed interaction probability matrices and compared them to the observed plant‐hummingbird matrix through a likelihood approach. Furthermore, a recently proposed modularity algorithm for weighted bipartite networks was employed to evaluate whether these factors also scale‐up to the formation of modules in the network. Interaction frequencies were best predicted by species morphology, phenology and habitat occupancy, while species abundances and nectar availability performed poorly. The plant–hummingbird network was modular, and modules were associated to morphological specialization and habitat occupancy. Our findings highlight the importance of traits as determinants of interaction frequencies and network structure, corroborating the results of a previous study on a plant–hummingbird network from the Brazilian Atlantic Forest. Thus, we propose that traits matter more in tropical plant–hummingbird networks than in less specialized systems. To test the generality of this hypothesis, future research could employ geographic or taxonomic cross‐system comparisons contrasting networks with known differences in level of specialization.  相似文献   

18.
Morphological and behavioural patterns were examined in a guild of nine species of eastern Australian cicadas. Co-occurrence in, and structure of, 44 study plots were determined to relate morphological and behavioural patterns to habitat overlap and habitat structure. Multi-variate analyses were employed to generate relationships between the species. Guild substructure shown by the habitat analyses cannot be predicted from the group substructure indicated by the morphology/behaviour analyses. Therefore, extant combinations appear to be random collections from the nine-species pool insofar as morphology and behaviour are concerned. In particular, the most generalized species (in terms of habitat) are relatively extreme in morphology and behaviour, and vice versa. Despite these results, there are weak indications that at least two suites of characters exist, and that one of them is associated with each of the most extreme types of habitat. The reasons for these apparently contradictory results are discussed. There is no evidence to suggest that systematic morphological divergence has occurred in this guild.  相似文献   

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In all sensory modalities, the data acquired by the nervous system is shaped by the biomechanics, material properties, and the morphology of the peripheral sensory organs. The rat vibrissal (whisker) system is one of the premier models in neuroscience to study the relationship between physical embodiment of the sensor array and the neural circuits underlying perception. To date, however, the three-dimensional morphology of the vibrissal array has not been characterized. Quantifying array morphology is important because it directly constrains the mechanosensory inputs that will be generated during behavior. These inputs in turn shape all subsequent neural processing in the vibrissal-trigeminal system, from the trigeminal ganglion to primary somatosensory ("barrel") cortex. Here we develop a set of equations for the morphology of the vibrissal array that accurately describes the location of every point on every whisker to within ±5% of the whisker length. Given only a whisker's identity (row and column location within the array), the equations establish the whisker's two-dimensional (2D) shape as well as three-dimensional (3D) position and orientation. The equations were developed via parameterization of 2D and 3D scans of six rat vibrissal arrays, and the parameters were specifically chosen to be consistent with those commonly measured in behavioral studies. The final morphological model was used to simulate the contact patterns that would be generated as a rat uses its whiskers to tactually explore objects with varying curvatures. The simulations demonstrate that altering the morphology of the array changes the relationship between the sensory signals acquired and the curvature of the object. The morphology of the vibrissal array thus directly constrains the nature of the neural computations that can be associated with extraction of a particular object feature. These results illustrate the key role that the physical embodiment of the sensor array plays in the sensing process.  相似文献   

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