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1.
合成生物学是21世纪前沿交叉学科,是现代生物学最具发展空间的领域之一.随着合成生物学的迅速发展,国际基因工程机器大赛(International Genetically Engineered Machine,iGEM)应运而生.iGEM竞赛项目基于合成生物学学科基础,应用现代生物学技术手段,立足解决社区和身边的实际生物...  相似文献   

2.
Phylogenies are increasingly prominent across all of biology, especially as DNA sequencing makes more and more trees available. However, their utility is compromised by widespread misconceptions about what phylogenies can tell us, and improved "tree thinking" is crucial. The most-serious problem comes from reading trees as ladders from "left to right"--many biologists assume that species-poor lineages that appear "early branching" or "basal" are ancestral--we call this the "primitive lineage fallacy". This mistake causes misleading inferences about changes in individual characteristics and leads to misrepresentation of the evolutionary process. The problem can be rectified by considering that modern phylogenies of present-day species and genes show relationships among evolutionary cousins. Emphasizing that these are extant entities in the 21(st) century will help correct inferences about ancestral characteristics, and will enable us to leave behind 19(th) century notions about the ladder of progress driving evolution.  相似文献   

3.
Cancer is a disease of multicellularity; it originates when cells become dysregulated due to mutations and grow out of control, invading other tissues and provoking discomfort, disability, and eventually death. Human life expectancy has greatly increased in the last two centuries, and consequently so has the incidence of cancer. However, how cancer patterns in humans compare to those of other species remains largely unknown. In this review, we search for clues about cancer and its evolutionary underpinnings across the tree of life. We discuss data from a wide range of species, drawing comparisons with humans when adequate, and interpret our findings from an evolutionary perspective. We conclude that certain cancers are uniquely common in humans, such as lung, prostate, and testicular cancer; while others are common across many species. Lymphomas appear in almost every animal analysed, including in young animals, which may be related to pathogens imposing selection on the immune system. Cancers unique to humans may be due to our modern environment or may be evolutionary accidents: random events in the evolution of our species. Finally, we find that cancer‐resistant animals such as whales and mole‐rats have evolved cellular mechanisms that help them avoid neoplasia, and we argue that there are multiple natural routes to cancer resistance.  相似文献   

4.
The placing of animal behaviour in an evolutionary context is one of the great achievements of biologists in the last century. Life history theory has been a powerful tool in explaining both adaptation and constraint in phenotypic evolution, but rarely addresses the mechanistic bases of the traits it discusses. Recent advances in molecular biology have begun to uncover these mechanisms, and provide a challenge to the traditional view that life history trade-offs are the result of the differential allocation of limiting resources. In particular, costs of reproduction in Caenorhabditis elegans appear to arise from molecular signals, which have been claimed to be arbitrary with respect to fitness. We review the evidence that costs of reproduction in C. elegans are not resource based, and find that this is not necessarily the case. However, we welcome the challenge to traditional thinking, and suggest that integrating an understanding of mechanisms into life history theory will be one of the most exciting tasks facing evolutionary biologists in the 21st century. Copyright 2003 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour.   相似文献   

5.
Vertebrate cranial placodes are crucial contributors to the vertebrate cranial sensory apparatus. Their evolutionary origin has attracted much attention from evolutionary and developmental biologists, yielding speculation and hypotheses concerning their putative homologues in other lineages and the developmental and genetic innovations that might have underlain their origin and diversification. In this article we first briefly review our current understanding of placode development and the cell types and structures they form. We next summarise previous hypotheses of placode evolution, discussing their strengths and caveats, before considering the evolutionary history of the various cell types that develop from placodes. In an accompanying review, we also further consider the evolution of ectodermal patterning. Drawing on data from vertebrates, tunicates, amphioxus, other bilaterians and cnidarians, we build these strands into a scenario of placode evolutionary history and of the genes, cells and developmental processes that underlie placode evolution and development.  相似文献   

6.
Today ballet is an integral part of life not only for those directly associated with that art but also for all those interested in this type of performance, people who have developed a sensitivity toward it. This article aims to show the prerequisites and strategies for the development of certain dress fashions in the 21st century that were influenced by the work of fashion designers specializing in ballet costumes. The article also advances a stylistic analysis of fashion in Soviet and post-Soviet society, in relation to three styles: modern, avant-garde and postmodern. In summary, the 21st century is seeing a revival of ballet, as a feature of the cultural life of Western society, and given modern trends, ballet will not lose its relevance.  相似文献   

7.
Bioturbation: a fresh look at Darwin's last idea   总被引:13,自引:0,他引:13  
Bioturbation refers to the biological reworking of soils and sediments, and its importance for soil processes and geomorphology was first realised by Charles Darwin, who devoted his last scientific book to the subject. Here, we review some new insights into the evolutionary and ecological role of bioturbation that would have probably amazed Darwin. In modern ecological theory, bioturbation is now recognised as an archetypal example of 'ecosystem engineering', modifying geochemical gradients, redistributing food resources, viruses, bacteria, resting stages and eggs. From an evolutionary perspective, recent investigations provide evidence that bioturbation had a key role in the evolution of metazoan life at the end of the Precambrian Era.  相似文献   

8.
Biological anthropology can, and should, matter in the Anthropocene. Biological anthropologists are interested in human biology and the human experience in a broader ecological, evolutionary, and phylogenetic context. We are interested in the material of the body, the history of the body, and interactions of diverse bodies, communities, ecologies, and evolutionary processes. However, the cultural realities of bodies, histories, communities, livelihoods, perceptions, and experiences are as central to the endeavor and inquiry of biological anthropology as are their material aspects. Biological anthropology is a constant dialectic between the cultural and the biological. In this essay, I argue that Biological Anthropology has much to offer, a history to contend with, and a future that matters. To illustrate this, I highlight theoretical and methodological issues in genomics, evolutionary theory and connect them to the study of Race and Racism to emphasize specific arenas where Biological Anthropology has a great capacity, and a strong obligation, to play a central role. However, Biological Anthropology also has substantive internal issues that hinder our ability to do the best possible science. If we are to live up to our potential and make a difference in the 21st century we need to ameliorate our structural shortcomings and expand our voice, and impact, in academic and public discourse. The goal of this perspective is to offer suggestions for moving us toward this goal.  相似文献   

9.
Two hundred years after Darwin's birth, our understanding of genetic mechanisms and cell biology has advanced to a level unimaginable in the 19th century. We now know that eukaryotic cells contain a huge variety of internal compartments, each with their own function, identity and history. For the compartments that together form the membrane-trafficking system, one of the central questions is how that identity is encoded and how it evolved. Here we review the key components involved in membrane-trafficking events, including SNAREs, Rabs, vesicle coats, and tethers and what is known about their evolutionary history. Our current understanding suggests a possible common mechanism by which the membrane-trafficking organelles might have evolved. This model of increased organellar complexity by gene duplication and co-evolution of multiple, interacting, specificity-encoding proteins could well be applicable to other non-endosymbiotic organelles as well. The application of basic evolutionary principles well beyond their original scope has been exceedingly powerful not only in reconstructing the history of cellular compartments, but for medical and applied research as well, and underlines the contributions of Darwin's ideas in modern biology.  相似文献   

10.
There must be a prokaryote somewhere: microbiology''s search for itself.   总被引:7,自引:2,他引:5  
While early microbiologists showed considerable interest in the problem of the natural (evolutionary) relationships among prokaryotes, by the middle of this century that problem had largely been discarded as being unsolvable. In other words, the science of microbiology developed without an evolutionary framework, the lack of which kept it a weak discipline, defined largely by external forces. Modern technology has allowed microbiology finally to develop the needed evolutionary framework, and with this comes a sense of coherence, a sense of identity. Not only is this development radically changing microbiology itself, but also it will change microbiology's relationship to the other biological disciplines. Microbiology of the future will become the primary biological science, the base upon which our future understanding of the living world rests, and the font from which new understanding of it flows.  相似文献   

11.
Gross M 《Current biology : CB》2011,21(21):R871-R873
Our closest hominid relatives may have died out 30,000 years before the arrival of the computer, but thanks to modern genomics and scanning technology, they are now very present in the 21st century and can even help us understand our own species.  相似文献   

12.
细菌耐药性是21世纪国际关注的重要问题,也是全球面临的重大挑战.肠杆菌科细菌是医院感染的重要病原菌之一.近年来,随着抗生素的大量使用,多种肠杆菌科耐药菌,尤其是多重耐药肠杆菌开始大量出现,对人类健康形成了日益严重的威胁.细菌可以通过耐药基因突变或水平转移的方式获得耐药性,通常情况下,可以通过已知的耐药机制预测相应的耐药...  相似文献   

13.
In the 21st century, researchers have attempted a synthesis between community ecology and evolutionary biology. This emerging research area, which aims to synthesize community ecology and evolutionary biology, is evolutionary community ecology. Evolutionary community ecology addresses how intraspecific trait variation in community members is essential for predicting community properties and, how community properties are a key component of the selective forces that determine genetic and phenotypic variation in a community member. In this paper, I review recent findings in evolutionary community ecology in plant-associated arthropods in terrestrial ecosystems. I discuss roles of both genetic variation and phenotypic plasticity as a source of trait variation in plants in shaping plant-associated arthropod communities. Also, I discuss effects of genetic variation in herbivores on plant-associated arthropod communities. Furthermore, I highlight community context evolution in which multiple species interactions and community composition affect trait evolution of a community member. Finally, I argue that future studies should investigate a feedback loop between community and evolutionary dynamics beyond unidirectional studies on effects of evolution on a community or vice versa. This approach will provide major insights into mechanistic principles for making predictions of community ecology.  相似文献   

14.
Alexander Kowalevsky was one of the most significant 19th century biologists working at the intersection of evolution and embryology. The reinstatement of the Alexander Kowalevsky Medal by the St. Petersburg Society of Naturalists for outstanding contributions to understanding evolutionary relationships in the animal kingdom, evolutionary developmental biology, and comparative zoology is timely now that Evo-devo has emerged as a major research discipline in contemporary biology. Consideration of the intellectual lineage of comparative evolutionary embryology explicitly forces a reconsideration of some current conceptions of the modern emergence of Evo-devo, which has tended to exist in the shadow of experimental embryology throughout the 20th century, especially with respect to the recent success of developmental biology and developmental genetics. In particular we advocate a sharper distinction between the heritage of problems and the heritage of tools for contemporary Evo-devo. We provide brief overviews of the work of N. J. Berrill and D. T. Anderson to illustrate comparative evolutionary embryology in the 20th century, which provides an appropriate contextualization for a conceptual review of our research on the sea urchin genus Heliocidaris over the past two decades. We conclude that keeping research questions rather than experimental capabilities at the forefront of Evo-devo may be an antidote to any repeat of the stagnation experienced by the first group of evolutionary developmental biologists over one hundred years ago and acknowledges Kowalevsky's legacy in evolutionary embryology.  相似文献   

15.
Understood in their historical context, current debates about psychiatric classification, prompted by the publication of the DSM‐5, open up new opportunities for improved translational research in psychiatry. In this paper, we draw lessons for translational research from three time slices of 20th century psychiatry. From the first time slice, 1913 and the publication of Jaspers' General Psychopathology, the lesson is that translational research in psychiatry requires a pluralistic approach encompassing equally the sciences of mind (including the social sciences) and of brain. From the second time slice, 1959 and a conference in New York from which our present symptom‐based classifications are derived, the lesson is that, while reliability remains the basis of psychiatry as an observational science, validity too is essential to effective translation. From the third time slice, 1997 and a conference on psychiatric classification in Dallas that brought together patients and carers with researchers and clinicians, the lesson is that we need to build further on collaborative models of research combining expertise‐by‐training with expertise‐by‐experience. This is important if we are to meet the specific challenges to translation presented by the complexity of the concept of mental disorder, particularly as reflected in the diversity of desired treatment outcomes. Taken together, these three lessons – a pluralistic approach, reliability and validity, and closer collaboration among relevant stakeholders – provide an emerging framework for more effective translation of research into practice in 21st century psychiatry.  相似文献   

16.
We present a review of the history of scientific inquiry into modern human origins, focusing on the role of the American Anthropologist . We begin during the mid–20th century, at the time when the problem of modern human origins was first presented in the American Anthropologist and could first be distinguished from more general questions about human and hominid origins. Next, we discuss the effects of the modern evolutionary synthesis on biological anthropology and paleoanthropology in particular, and its role in the origin of anthropological genetics. The rise of human genetics is discussed along two tracks, which have taken starkly different approaches to the historical interpretation of recent human diversity. We cover varying paleoanthropological interpretations, including paleoanthropologists' reactions to genetic interpretations. We hope to identify some of the crucial inflection points in which the debate went astray, to rectify some of the points of misunderstanding among current scientists, and to clarify the likely path ahead. [Keywords: multiregional evolution, recent African origin, bottleneck, polygenism, race]  相似文献   

17.
The birth of a language is a historical process, which develops through almost six stages corresponding to six main properties (genetic distance, geographical isolation, adoption of a writing system, elaboration of a literary koine, national consciousness, official status), which are specific to Western civilization and limited to our concern, i.e. the languages in contemporary Europe. The two last properties are the most important and conclusive in achieving the full status of language in contrast with dialect, speech, idiom, vernacular and so on. Consequently, in this perspective the birth of a language can be stated when its use is felt as a token of national identity and its official status is recognized by politic power. The history of some interesting cases during the 20th century, such as Luxemburgish, Feroese and Macedonian will throw a light on the possible future scenario of the languages of the Former Yugoslavia. Other disputed, although not so dramatic cases, like Sardinian, Aranese, Moldavian and Ruthenian, are dealt with together with recurrent topics on minority languages. The conclusion is that, unlike the worldwide tendency, the number of languages will probably increase within the greater European Union in the course of the 21st century.  相似文献   

18.
Over the past 25 years, new techniques, new discoveries, and new ideas have profoundly impacted our understanding of deuterostome interrelationships and, ultimately, deuterostome evolution. During the late 1980s and early 1990s morphological cladistic analyses made predictions about both taxonomic history and homology, predictions that would be tested independent of the morphological characters themselves with the advent of molecular systematics, the rise of evolutionary developmental biology, and continued exploration of the fossil record. Thanks to these three areas of inquiry, we have gone from scenarios where animals like mobile enteropneust hemichordates and chordates were derived from sessile filter-feeding animals like modern lophophorates, echinoderms, and pterobranch hemichordates, to a new perspective where hemichordates are recognized as the nearest living relative of the echinoderms, and that vagile gill-bearing animals like Cambrian vetulicolians are seen—at least by some—as close to the deuterostome last common ancestor, with both sessility and filter-feeding convergent features of deuterostomes (e.g., echinoderm) and non-deuterostomes (e.g., lophophorates) alike. Although much of the backbone of the new deuterostome phylogeny is supported by multiple independent data sets, as are statements of homology of several different morphological characters, in particular the homology of gill slits across Deuterostomia, nonetheless, the next quarter century of study on this remarkable group of animals promises to be as equally illuminating and exciting as the past quarter century.  相似文献   

19.
System-level approaches in biology are not new but foundations of “Systems Biology” are achieved only now at the beginning of the 21st century [Kitano, H., 2001. Foundations of Systems Biology. MIT Press, Cambridge, MA]. The renewed interest for a system-level approach is linked to the progress in collecting experimental data and to the limits of the “reductionist” approach. System-level understanding of native biological and pathological systems is needed to provide potential therapeutic targets. Examples of interdisciplinary approach in Systems Biology are described in U.S., Japan and Europe. Robustness in biology, metabolic engineering and idiotypic networks are discussed in the framework of Systems Biology.  相似文献   

20.
Predicting and understanding the biological response to future climate change is a pressing challenge for humanity. In the 21st century, many species will move into higher latitudes and higher elevations as the climate warms. In addition, the relative abundances of species within local assemblages are likely to change. Both effects have implications for how ecosystems function. Few biodiversity forecasts, however, take account of both shifting ranges and changing abundances. We provide a novel analysis predicting the potential changes to assemblage‐level relative abundances in the 21st century. We use an established relationship linking ant abundance and their colour and size traits to temperature and UV‐B to predict future abundance changes. We also predict future temperature driven range shifts and use these to alter the available species pool for our trait‐mediated abundance predictions. We do this across three continents under a low greenhouse gas emissions scenario (RCP2.6) and a business‐as‐usual scenario (RCP8.5). Under RCP2.6, predicted changes to ant assemblages by 2100 are moderate. On average, species richness will increase by 26%, while species composition and relative abundance structure will be 26% and 30% different, respectively, compared with modern assemblages. Under RCP8.5, however, highland assemblages face almost a tripling of species richness and compositional and relative abundance changes of 66% and 77%. Critically, we predict that future assemblages could be reorganized in terms of which species are common and which are rare: future highland assemblages will not simply comprise upslope shifts of modern lowland assemblages. These forecasts reveal the potential for radical change to montane ant assemblages by the end of the 21st century if temperature increases continue. Our results highlight the importance of incorporating trait–environment relationships into future biodiversity predictions. Looking forward, the major challenge is to understand how ecosystem processes will respond to compositional and relative abundance changes.  相似文献   

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