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硒的化学与生物形态分析综述

光谱学与光谱分析 2002年第2期22卷 331-340页

作者：徐芳邱德仁杨芃原胡克季复旦大学化学系上海200433 复旦大学分析测试中心上海200433

硒是人体必需的微量元素。其特殊的生理、生化功能不仅取决于硒的总浓度水平 ,而且同不同化学生物形态下硒的存在密切相关。硒的分析研究在生命科学、环境科学、医药科学等领域日益活跃。本文就近年来在硒分析方面发表的有关文献 ,从样... 详细信息

硒是人体必需的微量元素。其特殊的生理、生化功能不仅取决于硒的总浓度水平 ,而且同不同化学生物形态下硒的存在密切相关。硒的分析研究在生命科学、环境科学、医药科学等领域日益活跃。本文就近年来在硒分析方面发表的有关文献 ,从样品的采集条件、储存条件、消解过程、总量测定、特别是应用各种联用技术进行硒化物形态分析等诸方面 ,作出较系统全面的综述。

关键词：综述硒化学形态生态形态形态分析微量元素生理功能生化功能

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鸟类肌肉系统研究综述

动物学杂志 1999年第5期34卷 41-45页

作者：张子慧首都师范大学生物系北京100037

鸟类肌肉的结构与功能在系统进化研究方面有重要的意义,一直是鸟类形态学研究的重点之一.深入进行比较研究不仅可以解释结构、功能的相关以及形态与生态的适应,而且还可以为进化、系统分类等方面的研究提供有价值的依据.

关键词：鸟类肌肉系统解剖学功能形态生态形态

How might epigenetics contribute to ecological speciation？

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Current Zoology 2013年第5期59卷 686-696页

作者： Gilbert SMITH Michael G. RITCHIE Department of Ecology and Evolutionary Biology University of California Irvine California USA School of Biology University of St Andrews St Andews Fife KY16 9TH Scotland UK

Speciation research has seen a renewed interest in ecological speciation, which emphasises divergent ecological selection leading to the evolution of reproductive isolation. Selection from divergent ecologies means that phenotypic plasticity can play an important role in ecological speciation. Phenotypic plasticity involves the induction of phenotypes over the lifetime of an organism and emerging evidence suggests that epigenetic marks such as cytosine and protein (histone) modifications might regulate such environmental induction. Epigenetic marks play a wide role in a variety of processes including development, sex differentiation and allocation, sexual conflict, regulation of transposable elements and phenotypic plasticity. Here we describe recent studies that investigate epigenetic mechanisms in a variety of contexts. There is mounting evidence for environmentally induced epigenetic variation and for the stable inheritance of epigenetic marks between generations. Thus, epigenetically-based phenotypic plasticity may play a role in adaptation and ecological speciation. However, there is less evidence for the inheritance of induced epigenetic variation across multiple generations in animals. Currently few studies of ecological speciation incorporate the potential for the involvement of epigenetically-based induction of phenotypes, and we argue that this is an important omission.

关键词：生态形态表观遗传表型可塑性学会遗传标记环境感应生殖隔离生命周期

The geography of introgression in a patchy environment and the thorn in the side of ecological speciation

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Current Zoology 2013年第1期59卷 72-86页

作者： Nicolas BIERNE Universit6 Montpellier 2 Place Eugene Bataillon 34095 Montpellier Cedex 5 France ISEM - CNRS UMR 5554 SMEL 2 rue des Chantiers 34200 S6te France CEFE - CNRS UMR 5175 34293 MontpeUier Cedex 5 France

When incompletely isolated taxa coexist in a patchy environment (e.g. mosaic hybrid zones, host-race complexes), patterns of variation may differ between selected traits/genes and neutral markers. While the genetic structure of selected traits/loci tends to coincide with habitat variables (producing Genetic-Environment Association or GEA), genetic differentiation at neutral loci unlinked to any selected locus rather depends on geographic connectivity at a large scale (e.g. Isolation-By-Distance or IBD), although these loci often display GEA at a small scale. This discrepancy has been repeatedly taken as evidence for parallel primary divergence driven by local adaptation. We argue that this interpretation needs to be addressed more thoroughly by considering the alternative hypothesis that speciation was initiated in allopatry and secondary introgression has subsequently erased the signal of past differentiation at neutral loci. We present a model of neutral introgression after secondary contact in a mosaic hybrid zone, which describes how GEAs dissipate with time and how neutral variation self-organizes according to the environmental and geographic structures. We show that although neutral loci can be affected by environmental selection, they are often more affected by history and connectivity: the neutral structure retains the initial geographic separation more than it correlates with the environment during the colonization and introgression phases, and then converges to a migration-drift balance, the most frequent outcome of which is GEA at a local scale but IBD at a large scale. This is the exact pattern usually attributed to parallel ecological speciation. Introgression is heterogeneous in space and depends on the landscape structure (e.g. it is faster in small patches, which are more impacted by immigration). Furthermore, there is no directionality in the association and it is possible to observe reversed GEAs between distant regions. We argue that the history of differentiation should ideally be reconstructe

关键词：地理分隔生态形态环境相修补遗传结构遗传分化选择性状基因渗入

Developmental rate： A unifying mechanism for sympatric divergence in postglacial fishes？

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Current Zoology 2012年第1期58卷 21-34页

作者： Mcphee, Megan V. Noakes, David L. G. Allendorf, Fred W. Fisheries Division University of Alaska Fairbanks Juneau Alaska 99801 USA Department of Fisheries and Wildlife and Oregon Hatchery Research Center Oregon State University Corvallis Oregon 97331-3803 USA Division of Biological Sciences University of Montana Missoula MT 59812 USA

Morphologically divergent ecotypes arise in fish populations on postglacial time scales, and resource polymorphisms are often invoked to explain their origin. However, genetic recombination can constrain the ability of divergent selection to produce reproductive isolation in sympatry. Recombination breaks up favorable combinations of traits (“adaptive suites”) if individual traits are affected by different loci. Recombination also breaks up any association between traits under divergent selection and traits contributing to reproductive isolation. Thus, ecological speciation in the absence of preexisting barriers to gene flow is more likely when pleiotropy minimizes the number of loci involved. Here, we revisit research conducted by Carl Hubbs in the early 1900s on the effects of developmental rate on morphological traits in fishes. Hubbs’ work provides a mechanism to explain how sympatric divergence by trophic polymorphism can occur despite the challenges of recombination. We consider the implications of Hubbs’ observations for ecological speciation with gene flow in fishes, as well as rapid evolution in captive fish populations.

关键词：鱼类种群发展速度机制冰后期基因重组分化生态形态生殖隔离

Ecological speciation in Darwin＇s finches： Parsing the effects of magic traits

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Current Zoology 2013年第1期59卷 8-19页

作者： Jeffrey PODOS Rie DYBBOE Mads Ole JENSEN Department of Biology University of Massachusetts Amherst MA 01003 USA Department of Biology University of Copenhagen The August Krogh Bldg. Universitetsparken 13 DK-2100 CopenhagenDenmark Horsens Statsskole Studenterwenget 2 7000 Horsens Denmark

Many recent studies of ecological speciation have focused on “magic trait” scenarios, in which divergent selection on viability traits leads inextricably to corresponding divergence in mechanisms, especially mate recognition systems, that facilitate assortative mating. Speciation however may also proceed via other scenarios, such as when populations experience directly selected or random divergence in mate recognition systems. The relative contributions of magic trait versus other scenarios for speciation remain virtually unexplored. The present study aims to test the relative contribution of the magic trait scenario in the divergence of populations of the medium ground finchGeospiza fortisof Santa Cruz Island, Galapagos. First, we assess differences inG. fortissong between a northern population (Borrero Bay) and a southeastern population (El Garrapatero), differences that we propose (along with other within-island geographic song variations) have arisen via scenarios that do not involve a magic trait scenario. Pairwise comparisons of raw and composite (PC) song parameters, as well as discriminant functions analyses, reveal significant patterns of song divergence between sites. Second, we test the ability of territorial males at Borrero Bay to discriminate songs from the two sites. We find thatG. fortismales can discriminate within-island song variants, responding more strongly to local than to “foreign” songs, along 3 raw and 1 composite response measures. Third, we compare these findings to prior data sets on song divergence and discrimination in Santa CruzG. fortis. These comparisons suggest that song divergence and discrimination are shaped less strongly by geographic sources than by morphological (beak-related) sources. We thus argue that interpopulation song divergence and discrimination, fundamental elements of assortative mating in Darwin’s finches, can be fostered in early stages of divergence under magic trait as well as alternative scenarios for speciation, but with more emphasis on the magic trait sce

关键词：生态形态达尔文性状魔法解析识别系统相对贡献地理来源

The consequences of genomic architecture on ecological speciation in postglacial fishes

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Current Zoology 2013年第1期59卷 53-71页

作者： Sean M. ROGERS Jonathan A. MEE Ella BOWLES Department of Biological Sciences University of Calgary 2500 University Drive NW Calgary Alberta T2N 1N4 Canada

The quest for the origin of species has entered the genomics era. Despite decades of evidence confirming the role of the environment in ecological speciation, an understanding of the genomics of ecological speciation is still in its infancy. In this review, we explore the role of genomic architecture in ecological speciation in postglacial fishes. Growing evidence for the number, location, effect size, and interactions among the genes underlying population persistence, adaptive trait divergence, and reproductive isolation in these fishes reinforces the importance of considering genomic architecture in studies of ecological speci-ation. Additionally, these populations likely adapt to new freshwater environments by selection on standing genetic variation, as de novo mutations are unlikely under such recent divergence times. We hypothesize that modular genomic architectures in postglacial fish taxa may be associated with the probability of population persistence. Empirical studies have confirmed the genic nature of ecological speciation, implicating surprisingly extensive linkage disequilibrium across the genome. An understanding of these genomic mosaics and how they contribute to reproductive barriers remains unclear, but migration rates and the strength of selection at these loci is predicted to influence the likelihood of population divergence. Altogether, understanding the role of ge-nomic architecture is an important component of speciation research and postglacial fishes continue to provide excellent organisms to test these questions, both from the perspective of variation in architectures among taxa, and with respect to the distinct environments they have colonized. However, more empirical tests of ecological speciation predictions are needed.

关键词：基因组结构生态形态鱼类生态冰后期淡水环境连锁不平衡基因组学相互作用

Ecological speciation： Selection and the origin of species

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Current Zoology 2013年第1期59卷 1-7页

作者： Janette W. Boughmant Guest Editor Michigan State Univ BEACON Ctr Evolut Act Ecol Evolutionary Biol & Be E Lansing MI 48824 USA

The past 20 years have seen a renaissance in the study of speciation.At the core of this research endeavor is the study of ecological speciation,and substantial evidence has been marshaled revealing that much of the world's biodiversity arises through this process (Seehausen,2006;Schluter,2009).Ecological speciation comes about when selection that differs between contrasting environments causes the evolution of reproductive isolation.One of the surprises has been the realization that reproductive isolation can evolve very rapidly,even within tens or hundreds of generations (Hendry et al.2007).

关键词：生态形态物种起源生殖隔离生物多样性孤立

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论辩证思维的发展及其现代形态

华南师范大学学报（社会科学版） 1996年第1期 27-31,156页

作者：张尚仁广东(华南师范大学)行政学院

辩证思维的发展经历了从矛盾形态到系统形态再到生态形态的转换.矛盾形态的辩证思维概括为“一分为二”,抓住了核心,但存在导致将复杂对象简单化的危险;与矛盾思维相比,系统思维更能把握对象的全面性和内容的丰富性;在矛盾形态和系统形... 详细信息

辩证思维的发展经历了从矛盾形态到系统形态再到生态形态的转换.矛盾形态的辩证思维概括为“一分为二”,抓住了核心,但存在导致将复杂对象简单化的危险;与矛盾思维相比,系统思维更能把握对象的全面性和内容的丰富性;在矛盾形态和系统形态基础上发展起来的生态形态的辩证思维,则进一步强调了对象与外部环境的辩证关系及对象的历史演化和未来发展,因而应成为现代形态的辩证思维方式.

关键词：辩证思维矛盾形态系统形态生态形态