• Title/Summary/Keyword: evolutionary biology

Search Result 245, Processing Time 0.044 seconds

Development of an Effective Strategy to Teach Evolution

  • Ha, Min-Su;Cha, Hee-Young
    • Journal of The Korean Association For Science Education
    • /
    • v.31 no.3
    • /
    • pp.440-454
    • /
    • 2011
  • This study proposes a new instructional strategy and corresponding materials designed from various alternative frameworks to help students understand evolution as a biologically acceptable theory. Biology teachers have normally taught the evolutionary mechanism by means of comparing Lamarckism with natural selection. In this study, a new instructional strategy in which the Lamarckian explanation is first excluded because Lamarckism is known to be subsumed in a learner's cognitive structure as a strong preconception of evolution is suggested for teaching evolution. After mutation theory is introduced, Darwinism including natural selection is explained separately during the next class hour. Corresponding instructional materials that aid student understanding of the evolutionary mechanism were developed using recently published articles on human genetic traits as scientific evolutionary evidence instead of the traditional evolutionary subject matter, giraffe neck. Evolutionary evidence from human genetic traits allows students to exclude anthropocentric thoughts effectively and raise concern for the phenomenon of evolution positively. The administered instructional strategy and materials in this research improved student conception, concern, and belief of evolution and it is believed that they helped students understand the evolutionary mechanism effectively.

Analysis of Evolutionary Content in High School Biology Textbook (고등학교 생물 교과서에서의 진화내용분석)

  • Kim, Hak-Hyun;Chang, Nam-Kee
    • Journal of The Korean Association For Science Education
    • /
    • v.23 no.5
    • /
    • pp.470-483
    • /
    • 2003
  • This study analyzed the evolutionary content in 13 textbooks developed from the first to the 6th high school biology curriculum, The content analysis of textbooks, which were delineated nine component, was performed on the 80 evolutionary categories, According to the result, the proportion of the total evolutionary content in textbook increased from the textbooks developed by the Ist curriculum to the textbooks developed by the 6th curriculum, but the proportion of 'main narrative' in total evolutionary content was gradually decreased. It also showed that biology curriculum and points of view of textbook writers influenced on the proportion of evolutionary contents. On the whole, the topics of analysed textbooks exhibit insufficient diversity, Any categories- 'group selection', 'gene selection', 'gaps in fossil record', 'co-evolution', 'punctuated equilibrium', 'mosaic evolution', 'place of labor in human evolution', 'human race differentiation', 'criticism of "ontogeny recapitulates phylogeny", and 'human activities affecting evolution' - were not treated and others - 'theory of neutralism', 'theories of major episodes(excepting extinctions) found in the geologic time scale', 'sympatric speciation', 'clinal and area-effect speciation', 'polyploidy and evolution', 'gradualism' and 'evolution and origin of mammals' - were treated very lightly, the most emphasized topic was 'phylogeny in general' and 'formation of precells', 'miscellaneous' in the order of emphasis. 'Theory of natural selection' was lightly treated as just one of evolutionary theory though it should be emphasized as major theme of evolution. Also, the law of recapitulation, of which biologists doubt the validity, was discussed as an evidence of evolution in some textbooks. And the agents of genetic equilibrium disruption like genetic drift and migration were treated as of little importance. On the basis of above result, it was suggested that the textbook writers introduced the more meaningful evolutionary topics focused the theory of natural selection in explanation of evolution and evolution theory.

Checklist of Hymenomycetes (Aphyllophorales s.l.) and Heterobasidiomycetes in Israel

  • Tura, Daniel;Zmitrovich, Ivan V.;Wasser, Solomon P.;Nevo, Eviatar
    • Mycobiology
    • /
    • v.38 no.4
    • /
    • pp.256-273
    • /
    • 2010
  • A checklist is presented concerning the species composition of Hymenomycetes (Aphyllophorales s.l.) and Heterobasidiomycetes in Israel based on data of previous studies and field sample collections. In total, 242 species are presented, of which five are new records for the Israeli mycobiota, namely Australohydnum dregeanum, Ceriporiopsis consobrina, C. resinascens, Fibroporia vaillantii, and Postia inocybe. The distribution and habitat of each species in Israel are also summarized. This checklist will serve as valuable data for future species diversity studies of these fungi in Israel.

Expression of CyI Cytoplasmic Actin Genes in Sea Urchin Development

  • Hahn, Jang-Hee;Raff, Rudolf A.
    • BMB Reports
    • /
    • v.29 no.5
    • /
    • pp.474-480
    • /
    • 1996
  • We present a study of evolutionary changes in expression of actin genes among closely related sea urchin species that exhibit different modes of early development. For this purpose, polyclonal antisera raised against peptides from the carboxyl terminus of the HeCyI cytoskeletal actin of Heliocidaris erythrogramma were used. H. erythrogramma is a direct developing sea urchin that proceeds from embryonic to adult stages without an intervening feeding larval stage. Expression patterns of the CyI actin isoform were compared with those of Heliocidaris tuberculata and to a related sea urchin Strongylocentrotus purpuratus, which both produce a feeding pluteus larval stage. The CyI actin of all three species is expressed in the same cell types. However, its expression patterns have been changed with reorganization of early cell lineage differentiation, which is apparent among the three species. Thus. evolutionary changes in CyI actin gene expression patterns are correlated with not only phylogenetic relationship, but developmental mode. The implication of this observation is that evolutionary changes in expression patterns of histospecific genes may underlie the emergence of novel developmental processes.

  • PDF

Model development in freshwater ecology with a case study using evolutionary computation

  • Kim, Dong-Kyun;Jeong, Kwang-Seuk;McKay, Robert Ian (Bob);Chon, Tae-Soo;Kim, Hyun-Woo;Joo, Gea-Jae
    • Journal of Ecology and Environment
    • /
    • v.33 no.4
    • /
    • pp.275-288
    • /
    • 2010
  • Ecological modeling faces some unique problems in dealing with complex environment-organism relationships, making it one of the toughest domains that might be encountered by a modeler. Newer technologies and ecosystem modeling paradigms have recently been proposed, all as part of a broader effort to reduce the uncertainty in models arising from qualitative and quantitative imperfections in the ecological data. In this paper, evolutionary computation modeling approaches are introduced and proposed as useful modeling tools for ecosystems. The results of our case study support the applicability of an algal predictive model constructed via genetic programming. In conclusion, we propose that evolutionary computation may constitute a powerful tool for the modeling of highly complex objects, such as river ecosystems.

Species Diversity of Hypogeous Ascomycetes in Israel

  • Barseghyan, Gayane S.;Wasser, Solomon P.
    • Mycobiology
    • /
    • v.38 no.3
    • /
    • pp.159-165
    • /
    • 2010
  • We conducted a species diversity study of the hypogeous Ascomycetes of Israel. The hypogeous Ascomycetes in Israel include members of the families Pyronemataceae, Pezizaceae, and Tuberaceae, which are represented by seven species: Hydnocystis piligera, Terfezia arenaria, T. claveryi, T. oligosperma, Tirmania africana, Tuber asa, and T. nitidum; only T. asa is new to Israeli mycobiota. Synonymy, locations, collection data, general distribution, distribution in Israel, descriptions, a key to identification, illustrations, and taxonomic remarks are provided.