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1.
Today, the picture of an evolutionary tree is a very well-known visual image. It is almost impossible to think of the ancestry and relationships of living beings without it. As natural history museums play a major role in the public understanding of evolution, they often present a wide variety of evolutionary trees. However, many studies have shown (Baum and Offner 2008; Baum et al. 2005; Catley and Novick 2008; Evans 2009; Gregory 2008; Matuk 2007; Meir et al. 2007b; Padian 2008) that even though evolutionary trees have the potential to engage visitors of natural history museums with the phenomena of evolution, many of them unwittingly might lead to misunderstandings about the process. As valuable research and educational institutions, one of the museum’s important missions should be the careful design of their exhibits on evolution considering, for example, common preconceptions visitors often bring, such as the notion that evolution is oriented from simple toward complex organisms (incarnating the idea of a single ladder of life amidst the extraordinary diversity of organisms) and that humans are at the pinnacle of the evolutionary story, as well as na?ve interpretations of phylogenies. Our aim in this article is to show from history where many of these misunderstandings come from and to determine whether five important Western natural history museums inadvertently present “problematic” evolutionary trees (which might lead to non-scientific notions).  相似文献   

2.
Yang M  Wyckoff GJ 《Genetica》2011,139(5):639-648
The neutral theory of molecular evolution (Kimura 1985) is the basis for most current statistical tests for detecting selection, mainly using polymorphism data within species, divergence data between species, and/or genomic structures like linkage disequilibrium (Wang et al. 2006). In most cases informative tests can only be constructed with ample variations within these parameters and many common tests are difficult to formulate when identity-by-descent is not clear, for example in gene families or repetitive elements. With the current progress being made toward whole-genome sequencing and re-sequencing efforts, as well as protein sequencing via tandem mass spectrometry where genomic sequencing is lacking, we felt it was necessary to re-visit possible methods for rapid screening and detection of evolutionary outliers. These outliers might be of interest for other research, such as candidate gene association studies or genome annotations, drug- and disease-target searches, and functional studies. We focused on methods that would work on both protein and nucleotide data, could be used on large gene or protein domain families, and could be generated quickly in order for “first pass” annotation of large scale data. For these reasons, we chose properties of trees generated routinely in molecular phylogenetic studies; genetic distance, tree shape and balance, and internal node statistics (Heard 1992). Our current research looking at protein domain family data and phylogenetic trees from PFAM (Finn et al. 2008) suggests this approach towards detecting evolutionary outliers is feasible, but additional work will be necessary to determine the parameters that suggest either positive or negative selection is occurring in specific gene families. This is particularly true when other factors such as rapid duplication and deletion of genes containing these domains is taking place, and we suggest phylogenetic statistics may be useful in combination with existing methodologies for detailed studies of gene family data.  相似文献   

3.
According to some recent arguments, (Joyce in The evolution of morality, MIT Press, Cambridge, 2006; Ruse and Wilson in Conceptual issues in evolutionary biology, MIT Press, Cambridge, 1995; Street in Philos Studies 127: 109–166, 2006) if our moral beliefs are products of natural selection, then we do not have moral knowledge. In defense of this inference, its proponents argue that natural selection is a process that fails to track moral facts. In this paper, I argue that our having moral knowledge is consistent with, (a) the hypothesis that our moral beliefs are products of natural selection, and (b) the claim (or a certain interpretation of the claim) that natural selection fails to track moral facts. I also argue that natural selection is a process that could track moral facts, albeit imperfectly. I do not argue that we do have moral knowledge. I argue instead that Darwinian considerations provide us with no reason to doubt that we do, and with some reasons to suppose that we might.  相似文献   

4.
Here we address three misconceptions stated by Rice et al. in their observations of our article Paz-y-Mi?o and Espinosa (Evo Edu Outreach 2:655–675, 2009), published in this journal. The five authors titled their note “The Theory of Evolution is Not an Explanation for the Origin of Life.” First, we argue that it is fallacious to believe that because the formulation of the theory of evolution, as conceived in the 1800s, did not include an explanation for the origin of life, nor of the universe, the concept of evolution would not allow us to hypothesize the possible beginnings of life and its connections to the cosmos. Not only Stanley Miller’s experiments of 1953 led scientists to envision a continuum from the inorganic world to the origin and diversification of life, but also Darwin’s own writings of 1871. Second, to dismiss the notion of Rice et al. that evolution does not provide explanations concerning the universe or the cosmos, we identify compelling scientific discussions on the topics: Zaikowski et al. (Evo Edu Outreach 1:65–73, 2008), Krauss (Evo Edu Outreach 3:193–197, 2010), Peretó et al. (Orig Life Evol Biosph 39:395–406, 2009) and Follmann and Brownson (Naturwissenschaften 96:1265–1292, 2009). Third, although we acknowledge that the term Darwinism may not be inclusive of all new discoveries in evolution, and also that creationists and Intelligent Designers hijack the term to portray evolution as ideology, we demonstrate that there is no statistical evidence suggesting that the word Darwinism interferes with public acceptance of evolution, nor does the inclusion of the origin of life or the universe within the concept of evolution. We examine the epistemological and empirical distinction between the theory of evolution and the concept of evolution and conclude that, although the distinction is important, it should not compromise scientific logic.  相似文献   

5.
More than 25 years have passed since publication of the first comprehensive multi-authored landmark volume on the population biology and evolution of clonal organisms (Jackson et al. 1985). Since then, no less than eight symposium volumes or special issues have appeared in scientific journals reporting on advances in the field of clonal plant research, indicating that the study of clonal organisms has remained an important topic in ecological research. The three most recent overviews were published in special issues of this journal (Stuefer et al. 2000; Tolvanen et al. 2004; Sammul et al. 2008), and these are now supplemented with a fourth special issue of Evolutionary Ecology. The articles published here reflect some of the most important contributions to a workshop on clonal plant biology held in Leuven (Belgium) in July 2009 and they illustrate some major advances that have been made over the last few years. In the following paragraphs, we first summarize some representative contributions to the current issue, and second, we put forward some personal ideas about promising and underexplored research lines in clonal plant research.  相似文献   

6.
Primordial stages in feather evolution including an allegedly new type of protofeather (Xu et al. 2009) as reportedly identified in the Chinese dinosaurs were questioned (Lingham-Soliar in J Ornithol 2009) on identifications based on poor scientific methodology, errors and tautological rationalizations in critical issues. Criticisms were also directed at certain findings by Mayr et al. (2002) on integumental structures in the tail of a psittacosaur dinosaur from the early Cretaceous of China. Important allegations concerning a possible keratinous chemistry of the integumental structures and presence of a hollow lumen at their centre were considered poorly supported and consequently unsound. Mayr (2009) responded by questioning some of my remarks. Here, I respond to his comments.  相似文献   

7.

Background

How acceptance of evolution relates to understanding of evolution remains controversial despite decades of research. It even remains unclear whether cultural/attitudinal factors or cognitive factors have a greater impact on student ability to learn evolutionary biology. This study examined the influence of cultural/attitudinal factors (religiosity, acceptance of evolution, and parents’ attitudes towards evolution) and cognitive factors (teleological reasoning and prior understanding of natural selection) on students’ learning of natural selection over a semester-long undergraduate course in evolutionary medicine.

Method

Pre-post course surveys measured cognitive factors, including teleological reasoning and prior understanding of natural selection, and also cultural/attitudinal factors, including acceptance of evolution, parent attitudes towards evolution, and religiosity. We analyzed how these measures influenced increased understanding of natural selection over the semester.

Results

After controlling for other related variables, parent attitude towards evolution and religiosity predicted students’ acceptance of evolution, but did not predict students’ learning gains of natural selection over the semester. Conversely, lower levels of teleological reasoning predicted learning gains in understanding natural selection over the course, but did not predict students’ acceptance of evolution.

Conclusions

Acceptance of evolution did not predict students’ ability to learn natural selection over a semester in an evolutionary medicine course. However, teleological reasoning did impact students’ ability to learn natural selection.
  相似文献   

8.
Eighteen seventy-four was a high point in evolutionary embryology. Thanks to Charles Darwin, the theory of evolution by natural selection provided a revolutionary new way of viewing the relationships and origins of organisms on Earth. Thanks to Ernst Haeckel, embryos were the way to study evolution (Haeckel in Generelle morphologie der organismen, vols 1, 2. Verlag Georg Reimer, Berlin, 1866)—it really was embryos in evolution—and recapitulation was in the air. Thanks to Anton Dohrn, a new research facility was on the ground, designed, located and structured to facilitate the study of embryos in evolution. Anton Dohrn devised, designed, financed, supervised the construction and then administered the Naples Zoological Station specifically so that researchers from all nations would have a facility where Darwin’s theory of evolution by natural selection could be tested. The zoologists who took advantage of the brand new facility within weeks of its opening late in 1873 established lines of research into evolutionary embryology, the field we now know as evolutionary developmental biology (evo-devo), the study of embryos in evolution. I examine the approach taken by Ambrosius Hubrecht, the first Dutch embryologist to undertake research at the station, and then evaluate the research of three British zoologists—E. Ray Lankester, Albert Dew-Smith, and Francis Maitland (Frank) Balfour. All four sought insights into origins, especially vertebrate origins that rested on comparative embryology, homology, germ layers, and a Darwinian approach to origins.
Brian K. HallEmail:
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9.

Background  

In the clinical context, samples assayed by microarray are often classified by cell line or tumour type and it is of interest to discover a set of genes that can be used as class predictors. The leukemia dataset of Golubet al.[1] and the NCI60 dataset of Rosset al.[2] present multiclass classification problems where three tumour types and nine cell lines respectively must be identified. We apply an evolutionary algorithm to identify the near-optimal set of predictive genes that classify the data. We also examine the initial gene selection step whereby the most informative genes are selected from the genes assayed.  相似文献   

10.
Urban evolutionary biology is the study of rapid evolutionary change in response to humans and our uses of land to support city dwellers. Because cities are relatively modern additions to the natural world, research on urban evolution tends to focus on microevolutionary change that has happened across a few to many hundreds of generations. These questions still fall under the broad purview of evolutionary ecology. However, the severity, rapidity and replication of environmental changes that drive evolution in this context make it worthy of specific attention. Urban evolution provides the opportunity to study the earliest stages of evolution in a context that is scientifically interesting and societally important. The newness of urban populations and their proximity to natural populations also creates challenges when trying to detect population genetic change. In a From the Cover article in this issue of Molecular Ecology, Mueller et al. use whole genome resequencing data to address some of these challenges while exploring genetic changes associated with urbanization in three replicate urban‐rural burrowing owl (Athene cunicularia) populations. Combining multiple approaches across these sample sites Mueller et al. find evidence for selection on genes whose function is related to synapses, neuron projections, brain connectivity and cognitive function in general. That selection was parallel suggests that phenotypes related to brain processes were probably particularly important for urban adaptation.  相似文献   

11.
The Protein Kinase C family of enzymes is a group of serine/threonine kinases that play central roles in cell-cycle regulation, development and cancer. A key step in the activation of PKC is translocation to membranes and binding of membrane-associated activators including diacylglycerol (DAG). Interaction of novel and conventional isotypes of PKC with DAG and phorbol esters occurs through the two C1 regulatory domains (C1A and C1B), which exhibit distinct ligand binding selectivity that likely controls enzyme activation by different co-activators. PKC has also been implicated in physiological responses to alcohol consumption and it has been proposed that PKCα (Slater et al. J Biol Chem 272(10):6167–6173, 1997; Slater et al. Biochemistry 43(23):7601–7609, 2004), PKCε (Das et al. Biochem J 421(3):405–413, 2009) and PKCδ (Das et al. J Biol Chem 279(36):37964–37972, 2004; Das et al. Protein Sci 15(9):2107–2119, 2006) contain specific alcohol-binding sites in their C1 domains. We are interested in understanding how ethanol affects signal transduction processes through its affects on the structure and function of the C1 domains of PKC. Here we present the 1H, 15N and 13C NMR chemical shift assignments for the Rattus norvegicus PKCδ C1A and C1B proteins.  相似文献   

12.
Insights from human/mouse genome comparisons   总被引:4,自引:0,他引:4  
Large-scale public genomic sequencing efforts have provided a wealth of vertebrate sequence data poised to provide insights into mammalian biology. These include deep genomic sequence coverage of human, mouse, rat, zebrafish, and two pufferfish (Fugu rubripes and Tetraodon nigroviridis) (Aparicio et al. 2002; Lander et al. 2001; Venter et al. 2001; Waterston et al. 2002). In addition, a high-priority has been placed on determining the genomic sequence of chimpanzee, dog, cow, frog, and chicken (Boguski 2002). While only recently available, whole genome sequence data have provided the unique opportunity to globally compare complete genome contents. Furthermore, the shared evolutionary ancestry of vertebrate species has allowed the development of comparative genomic approaches to identify ancient conserved sequences with functionality. Accordingly, this review focuses on the initial comparison of available mammalian genomes and describes various insights derived from such analysis.  相似文献   

13.
Vallente RU  Cheng EY  Hassold TJ 《Chromosoma》2006,115(3):241-249
Meiotic prophase serves as an arena for the interplay of two important cellular activities, meiotic recombination and synapsis of homologous chromosomes. Synapsis is mediated by the synaptonemal complex (SC), originally characterized as a structure linked to pairing of meiotic chromosomes (Moses (1958) J Biophys Biochem Cytol 4:633–638). In 1975, the first electron micrographs of human pachytene stage SCs were presented (Moses et al. (1975) Science 187:363–365) and over the next 15 years the importance of the SC to normal meiotic progression in human males and females was established (Jhanwar and Chaganti (1980) Hum Genet 54:405–408; Pathak and Elder (1980) Hum Genet 54:171–175; Solari (1980) Chromosoma 81:315–337; Speed (1984) Hum Genet 66:176–180; Wallace and Hulten (1985) Ann Hum Genet 49(Pt 3):215–226). Further, these studies made it clear that abnormalities in the assembly or maintenance of the SC were an important contributor to human infertility (Chaganti et al. (1980) Am J Hum Genet 32:833–848; Vidal et al. (1982) Hum Genet 60:301–304; Bojko (1983) Carlsberg Res Commun 48:285–305; Bojko (1985) Carlsberg Res Commun 50:43–72; Templado et al. (1984) Hum Genet 67:162–165; Navarro et al. (1986) Hum Reprod 1:523–527; Garcia et al. (1989) Hum Genet 2:147–53). However, the utility of these early studies was limited by lack of information on the structural composition of the SC and the identity of other SC-associated proteins. Fortunately, studies of the past 15 years have gone a long way toward remedying this problem. In this minireview, we highlight the most important of these advances as they pertain to human meiosis, focusing on temporal aspects of SC assembly, the relationship between the SC and meiotic recombination, and the contribution of SC abnormalities to human infertility.The synaptonemal complex–50 years  相似文献   

14.
Siderophore production by marine-derived fungi   总被引:1,自引:0,他引:1  
  相似文献   

15.
16.
Several pilot experiments have indicated that improvements in older NMR structures can be expected by applying modern software and new protocols (Nabuurs et al. in Proteins 55:483–186, 2004; Nederveen et al. in Proteins 59:662–672, 2005; Saccenti and Rosato in J Biomol NMR 40:251–261, 2008). A recent large scale X-ray study also has shown that modern software can significantly improve the quality of X-ray structures that were deposited more than a few years ago (Joosten et al. in J. Appl Crystallogr 42:376–384, 2009; Sanderson in Nature 459:1038–1039, 2009). Recalculation of three-dimensional coordinates requires that the original experimental data are available and complete, and are semantically and syntactically correct, or are at least correct enough to be reconstructed. For multiple reasons, including a lack of standards, the heterogeneity of the experimental data and the many NMR experiment types, it has not been practical to parse a large proportion of the originally deposited NMR experimental data files related to protein NMR structures. This has made impractical the automatic recalculation, and thus improvement, of the three dimensional coordinates of these structures. We here describe a large-scale international collaborative effort to make all deposited experimental NMR data semantically and syntactically homogeneous, and thus useful for further research. A total of 4,014 out of 5,266 entries were ‘cleaned’ in this process. For 1,387 entries, human intervention was needed. Continuous efforts in automating the parsing of both old, and newly deposited files is steadily decreasing this fraction. The cleaned data files are available from the NMR restraints grid at .  相似文献   

17.
Tracy JL  Hart J  Martens JP 《PloS one》2011,6(3):e17349
The present research examined the psychological motives underlying widespread support for intelligent design theory (IDT), a purportedly scientific theory that lacks any scientific evidence; and antagonism toward evolutionary theory (ET), a theory supported by a large body of scientific evidence. We tested whether these attitudes are influenced by IDT's provision of an explanation of life's origins that better addresses existential concerns than ET. In four studies, existential threat (induced via reminders of participants' own mortality) increased acceptance of IDT and/or rejection of ET, regardless of participants' religion, religiosity, educational background, or preexisting attitude toward evolution. Effects were reversed by teaching participants that naturalism can be a source of existential meaning (Study 4), and among natural-science students for whom ET may already provide existential meaning (Study 5). These reversals suggest that the effect of heightened mortality awareness on attitudes toward ET and IDT is due to a desire to find greater meaning and purpose in science when existential threats are activated.  相似文献   

18.
My criticism of the »organism-centered concept of evolution« as exposed once again by Bonik et al. (this vol.) refers to its phylogenetic application but not to the underlying basic assumption. The misunderstanding is due to the fact that Bonik et al. do not distinguish between evolutionary theory (which is concerned with general problems) and phylogenetic research. Nobody would deny that organisms are energy converting systems. Variants with increased energetic efficiency will of course be favoured by natural selection. But this premise alone does not allow to reconstitute phylogenetic lineages. Evolutionary success of a given variant is determined by many other factors as, for instance, the presence or absence of certain predators. Therefore phylogenetic research depends largely on circumstantial evidence from compared anatomy. Finally it should be stressed that the elimination of »abnormal ontogenetic stages« does not contribute to phylogenetic transformation. Bonik et al. are wrong when they believe that this kind of internal selection constitutes a new, hitherto neglected element which necessitates a fundamental revision of evolutionary theory.  相似文献   

19.
The effect of herbivory and resource availability on the competitive ability of different plant species has been an area of intense debate amongst plant ecologists for at least two decades, but the interactive effects of herbivory and plant competition between woody and herbaceous plants are rarely studied and theory is poorly developed. This study used experimental manipulations on transplanted and naturally occurring mountain beech (Nothofagus solandri var. cliffortioides) seedlings to show the effects of deer browsing and competition from deer-induced, herbaceous turf communities on mountain beech regeneration in New Zealand. Differences in the species composition of these turfs had little effect on mountain beech seedling establishment, but turf removal increased seedling growth and survivorship, showing that competition with other plants had direct effects on mountain beech regeneration. Deer browsing reduced the establishment and growth of seedlings, but the size of this effect did not vary with light and nutrient availability. There was no immediate compositional response of turf communities following the removal of deer browsing. The addition of nutrients appeared to reduce the intensity of belowground competition (stem growth increased relative to root growth) and increase seedling mortality, but there was no effect of changing levels of light. These results showed simple and direct negative effects of deer browsing on mountain beech regeneration. Indirect negative effects on regeneration were caused by deer-induced turf communities. We found little evidence for interactive effects between herbivory, plant competition and the availability of light or nutrients on seedling regeneration, which suggests that these factors acted independently. Nomenclature: Beever et al. (1992); Parsons et al. (1995); Edgar and Connor (2000); and Brownsey and Smith-Dodsworth (2000). Raukaua simplex is described by Mitchell et al. (1997). Coprosma “taylorae” is referred to by Eagle (1986) and Halocarpus biformis, Phyllocladus alpinus, Podocarpus hallii and Podocarpus nivalis by Wilson and Galloway (1993).  相似文献   

20.
Meta-analysis is being increasingly used as a tool for integrating data from different studies of complex phenotypes, because the power of any one study to identify causal loci is limited. We applied a novel meta-analytical approach (Loesgen et al. in Genet Epidemiol 21(Suppl 1):S142–S147, 2001) in compiling results from four studies of rheumatoid arthritis in Caucasians including two studies from NARAC (Jawaheer et al. in Am J Hum Genet 68:927–936, 2001; Jawaheer et al. in Arthritis Rheum 48:906–916, 2003), one study from the UK (MacKay et al. in Arthritis Rheum 46:632–639, 2001) and one from France (Cornelis et al. in Proc Natl Acad Sci USA 95:10746–10750, 1998). For each study, we obtained NPL scores by performing interval mapping (2 cM intervals) using GeneHunter2 (Kruglyak et al. in Am J Hum Genet 58:1347–1363, 1996; Markianos et al. in Am J Hum Genet 68:963–977, 2001). The marker maps differed among the three consortium groups, therefore, the marker maps were aligned after the interval mapping was completed and the NPL scores that were within 1 cM of each other were combined using the method of Loesgen et al. (Genet Epidemiol 21(Suppl 1):S142–S147, 2001) by calculating the weighted average of the NPL score. This approach avoids some problems in analysis encountered by using GeneHunter2 when some markers in the sample are not genotyped. This procedure provided marginal evidence (P<0.05) of linkage on chromosome 1, 2, 5 and 18, strong evidence (P<0.01) on chromosomes 8 and 16, and overwhelming evidence in the HLA region of chromosome 6.  相似文献   

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