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Plant Behavior     
Plants are a huge and diverse group of organisms ranging from microscopic marine phytoplankton to enormous terrestrial trees. Stunning, and yet some of us take plants for granted. In this plant issue of LSE, WWW.Life Sciences Education focuses on a botanical topic that most people, even biologists, do not think about—plant behavior.Plants are a huge and diverse group of organisms (Figure 1), ranging from microscopic marine phytoplankton (see http://oceandatacenter.ucsc.edu/PhytoGallery/phytolist.html for beautiful images of many species) to enormous terrestrial trees epitomized by the giant sequoia: 300 feet tall, living 3000 years, and weighing as much as 3000 tons (visit the Arkive website, www.arkive.org/giant-sequoia/sequoiadendron-giganteum, for photos and basic information). Stunning, and yet some of us take plants for granted, like a side salad. We may see plants as a focal point during the blooming season or as a nice backdrop for all the interesting things animals do. For this plant issue of CBE—Life Sciences Education, I am going to focus on a botanical topic that most people, even biologists, do not think about—plant behavior.Open in a separate windowFigure 1.Plants are very diverse, ranging in size from microscopic plankton (left, courtesy of University of California–Santa Cruz Ocean Data Center) to the biggest organisms on our planet (right, courtesy Arkive.org).Before digging into plant behavior, let us define what a plant is. All plants evolved from the eukaryotic cell that acquired a photosynthetic cyanobacterium as an endosymbiont ∼1.6 billion years ago. This event gave the lineage its defining trait of being a eukaryote that can directly harvest sunlight for energy. The cyanobacteria had been photosynthesizing on their own for a long time already, but this new “plant cell” gave rise to a huge and diverse line of unicellular and multicellular species. Genome sequences have shed light on the birth and evolution of plants, and John Bowman and colleagues published an excellent review titled “Green Genes” several years ago in Cell (www.sciencedirect.com/science/article/pii/S0092867407004618#; Bowman et al., 2007 ). The article has concise information on the origin and evolution of plant groups, including helpful graphics (Figure 2). Of course, plants were classified and subdivided long before DNA analysis was possible. The Encyclopedia of Earth (EOE) is a good website for exploring biological diversity and has an article on plants (www.eoearth.org/view/article/155261) that lays out the major plant groups and their characteristics. It states that there are more than 400,000 described species, a fraction of the estimated total number.Open in a separate windowFigure 2.Genomic analysis has illuminated the relationship among the many species of plants, as illustrated in this phylogeny of three major plant groups from Bowman et al. (2007 , p. 129).The venerable Kew Gardens has an excellent website (Figure 3) that includes extensive pages under the tab Science and Conservation (www.kew.org/science-conservation). It is a beautifully organized website for exploring plant diversity and burrowing into the science of plants, and includes an excellent blog. Ever wonder how many different kinds of flowers there are? You can find out by visiting their feature titled, “How Many Flowering Plants Are There in the World?” There is an interesting video feature on coffee, which describes how only two species out of more than a hundred have come to dominate coffee production for drinking. As the monoculture in Ireland led to the potato blight, a lack of genetic diversity in today''s coffee plants is threatening the world''s coffee supply with the onset of climate change. The possibility of life without coffee is a call to action if ever I have heard one.Open in a separate windowFigure 3.Kew Gardens has a large and informative website that should appeal to gardeners and flower lovers, as well as more serious botanists and ecologists.Classification of plants is challenging for students and teachers alike. Perhaps understandable, given that plants constitute an entire kingdom of life. For an overview, have students read the EOE article as well as the Bowman Cell article to appreciate the enormity and diversity of the organisms we call plants. The EOE article is reproduced on the Encyclopedia of Life website (http://eol.org/info/449), an excellent context for further exploration of diverse plant species. As we probe the topic of plant behavior, the examples will be drawn from the vascular plants that include the many familiar plants commonly called trees, shrubs, flowers, vegetables, and weeds.Plants do respond to changes in their environment, but is it fruitful or scientifically valid to say that they have behavior? They lack muscles and nerves, do not have mouths or digestive systems, and are often literally rooted in place. A growing number of plant biologists have embraced the term behavior, as demonstrated by the journal devoted to the subject, Plant Behavior. Their resources page (www.plantbehavior.org/resources.html) is a good place to get oriented to the field.As in so many things, Darwin anticipated important questions concerning the movement of plants, despite the difficulties in observing plant behavior, and in 1880 he published The Power of Movement in Plants. The Darwin Correspondence Project website has a good treatment of Darwin''s work on plants, with interesting anecdotes relating to how he collaborated with his son Francis on this work late in his career (www.darwinproject.ac.uk/power-of-movement-in-plants). You can download Chapter 9 of the book and some of the correspondence between Darwin and his son. The entire book is available at http://darwin-online.org.uk/content/frameset?itemID=F1325&viewtype=text&pageseq=1, or in various e-reader formats at the Project Gutenberg website (http://www.gutenberg.org/ebooks/5605). The PBS NOVA website, has a feature covering several of Darwin''s “predictions,” including one in which he noted the importance of plant and animal interactions. He famously predicted that a Madagascar orchid (Angraecum sesquipedale), which has a long narrow passage to its nectar stash, must have a long-tongued pollinator. In 1903, biologists identified the giant hawkmoth, with a 12-inch-long proboscis, as the pollinator predicted by Darwin (www.pbs.org/wgbh/nova/id/pred-nf.html).Darwin recognized that plants mostly do things on a timescale that is hard for us to observe, so he devised clever ways to record their movements. Placing a plant behind a pane of glass, he marked the plant''s position on the glass over time using a stationary reference grid placed behind the plant. Darwin transferred the drawing to a sheet of paper before cleaning the glass for the next experiment (Figure 4). By varying the distance between the plant, the reference points, and the glass, he magnified apparent distances to detect even small plant movements over periods as short as minutes. High-definition time-lapse photography and other modern techniques have extended Darwin''s observations in some compelling directions.Open in a separate windowFigure 4.One of Darwin''s drawings that can be found on the Darwin Correspondence Project Web pages devoted to his book The Power of Movement in Plants. For this figure, the position of the cotyledons of a Brassica was marked on a glass plate about every 30 min over a period of more than 10 h.A recent episode of the PBS Nature series, “What Plants Talk About,” epitomizes the increased interest in plant behavior and, unfortunately, some of the hyperbole associated with the field. The time-lapse video sequences and associated science are fascinating, and the entire program can be viewed on the PBS website at http://video.pbs.org/video/2338524490. The home page for the program (Figure 5; www.pbs.org/wnet/nature/episodes/what-plants-talk-about/introduction/8228) has two short video clips that are interesting. The video titled “Dodder Vine Sniffs Out Its Prey” is nicely filmed and features some interesting experiments involving plant signaling. It might be instructive to ask students to respond to the vocabulary used in the narration, which unfortunately tries to impart intent and mindfulness to the plant''s activities, and to make sensible experimental results somehow seem shocking. The “Plant Self-Defense” video is a compelling “poison pill” story that needs no narrative embellishment. A plant responds to caterpillars feeding on it by producing a substance that tags them for increased attention from predators. Increased predation reduces the number of caterpillars feeding on the plants. The story offers a remarkable series of complex interactions and evolutionary adaptations. Another documentary, In the Mind of Plants (www.youtube.com/watch?v=HU859ziUoPc), was originally produced in French. Perhaps some experimental interpretations were mangled in translation, but the camera work is consistently excellent.Open in a separate windowFigure 5.The Nature pages of the PBS website have video clips and a short article, as well as the entire hour-long program “What Plants Talk About.” The program features fantastic camera work and solid science, but some questionable narration.Skepticism is part and parcel of scientific thinking, but particular caution may be warranted in the field of plant behavior because of the 1970s book and documentary called The Secret Life of Plants (www.youtube.com/watch?v=sGl4btrsiHk). The Secret Life of Plants was a sensation at the time and was largely responsible for the persistent myths that talking to your plants makes them healthier, that plants have auras, and that plants grow better when played classical music rather than rock. While the program woke people up to the notion that plants indeed do fascinating things, the conclusions based on bad science or no science at all were in the end more destructive than helpful to this aspect of plant science. Michael Pollan, author of The Botany of Desire and other excellent plant books, addresses some of the controversy that dogs the field of plant behavior in an interview on the public radio program Science Friday (http://sciencefriday.com/segment/01/03/2014/can-plants-think.html). His article “The Intelligent Plant” in the New Yorker (www.newyorker.com/reporting/2013/12/23/131223fa_fact_pollan?currentPage=all), covers similar ground.The excellently understated Plants in Motion website (http://plantsinmotion.bio.indiana.edu/plantmotion) is a welcome antidote to some of the filmic excesses. The site features dozens of low-definition, time-lapse videos of plants moving, accompanied by straightforward explanations of the experimental conditions and some background on the plants. The lack of narration conveys a refreshing cinema verité quality, and you can choose your own music to play while you watch. Highlights include corn shoots growing toward a light bulb, the rapid response of a mimosa plant to a flame, vines twining, and pumpkins plumping at night. You may have driven past a field of sunflowers and heard the remark that the heads follow the sun, but that is a partial truth. The young buds of the early plants do track the sun, but once they bloom, the tall plants stiffen and every head in the field permanently faces … east! The creators of Plants in Motion curated an exhibit at the Chicago Botanic Gardens called sLowlife (Figure 6). The accompanying video and “essay” (http://plantsinmotion.bio.indiana.edu/usbg/toc.htm) are excellent, featuring many interesting aspects of plant biology.Open in a separate windowFigure 6.sLowlife is an evocative multimedia essay designed to accompany an exhibit installed at the Chicago Botanic Gardens. It features text and video that reveal interesting aspects of plant biology.High-definition time-lapse photography is far from the only tool available to reveal hard-to-observe activities of plants. Greg Asner and colleagues at the Carnegie Airborne Observatory are using informatics to study the dynamic lives of plants at the community ecology level. The Airborne Observatory uses several impressive computer- and laser-enabled techniques (http://cao.stanford.edu/?page=cao_systems) to scan the landscape at the resolution of single leaves on trees and in modalities that can yield information at the molecular level. These techniques can yield insights into how forests respond to heat or water stress or the introduction of a new species. The site has a gallery of projects that are best started at this page: http://cao.stanford.edu/?page=research&pag=5. Here, they are documenting the effect of the Amazon megadrought on the rain forest. The very simple navigation at the top right consists of 15 numbered squares for the different projects. Each project is worth paging through to understand how versatile these aerial-mapping techniques are. They also have six buttons of video pages (http://cao.stanford.edu/?page=videos) that give you a feel for what it might be like to be in the air while collecting the data (Figure 7).Open in a separate windowFigure 7.The Carnegie Airborne Observatory is a flying lab that can collect real-time aerial data on forests at resolutions smaller than a single leaf on a tree.If this Feature seems to have been too conservative about whether plants have behavior, visit the LINV blog (www.linv.org/blog/category/plant-behavior) of the International Laboratory for Plant Neurobiology. The term “plant neurobiology” may be going too far, but the website presents some interesting science. Another fascinating dimension of plant “behavior” is seed dispersal, from seeds that can burrow, to seeds that “fly,” to seeds that are shot like bullets. A couple of websites have some good information and photos of the myriad designs that have evolved to take advantage of air currents for seed dispersal; see http://waynesword.palomar.edu/plfeb99.htm and http://theseedsite.co.uk/sdwind.html. The previously mentioned PBS Nature series also produced a program on seeds, “The Seedy Side of Plants,” which you can view at www.pbs.org/wnet/nature/episodes/the-seedy-side-of-plants/introduction/1268. ChloroFilms, a worldwide competition for plant videos, is now in its fourth season, with some really good videos (www.chlorofilms.org). If you love plants, work with plants, or have insights into plant biology, you should consider submitting a video!  相似文献   

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Functional studies have suggested the important role of early growth response 1 (EGR1) and Laminin α2-chain (LAMA2) in human eye development. Genetic studies have reported a significant association of the single nucleotide polymorphism (SNP) in the LAMA2 gene with myopia. This study aimed to evaluate the association of the tagging SNPs (tSNPs) in the EGR1 and LAMA2 genes with high myopia in two independent Han Chinese populations. Four tSNPs (rs11743810 in the EGR1 gene; rs2571575, rs9321170, and rs1889891 in the LAMA2 gene) were selected, according to the HapMap database (http://hapmap.ncbi.nlm.nih.gov), and were genotyped using the ligase detection reaction (LDR) approach for 167 Han Chinese nuclear families with extremely highly myopic offspring (<?10.0 diopters) and an independent group with 485 extremely highly myopic cases (<?10.0 diopters) and 499 controls. Direct sequencing was used to confirm the LDR results in twenty randomly selected subjects. Family-based association analysis was performed using the family-based association test (FBAT) software package (Version 1.5.5). Population-based association analysis was performed using the Chi-square test. The association analysis power was estimated using online software (http://design.cs.ucla.edu). The FBAT demonstrated that all four tSNPs tested did not show association with high myopia (P>0.05). Haplotype analysis of tSNPs in the LAMA2 genes also did not show a significant association (P>0.05). Meanwhile, population-based association analysis also showed no significant association results with high myopia (P>0.05). On the basis of our family- and population-based analyses for the Han Chinese population, we did not find positive association signals of the four SNPs in the LAMA2 and EGR1 genes with high myopia.  相似文献   

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Mathematical manipulative models have had a long history of influence in biological research and in secondary school education, but they are frequently neglected in undergraduate biology education. By linking mathematical manipulative models in a four-step process—1) use of physical manipulatives, 2) interactive exploration of computer simulations, 3) derivation of mathematical relationships from core principles, and 4) analysis of real data sets—we demonstrate a process that we have shared in biological faculty development workshops led by staff from the BioQUEST Curriculum Consortium over the past 24 yr. We built this approach based upon a broad survey of literature in mathematical educational research that has convincingly demonstrated the utility of multiple models that involve physical, kinesthetic learning to actual data and interactive simulations. Two projects that use this approach are introduced: The Biological Excel Simulations and Tools in Exploratory, Experiential Mathematics (ESTEEM) Project (http://bioquest.org/esteem) and Numerical Undergraduate Mathematical Biology Education (NUMB3R5 COUNT; http://bioquest.org/numberscount). Examples here emphasize genetics, ecology, population biology, photosynthesis, cancer, and epidemiology. Mathematical manipulative models help learners break through prior fears to develop an appreciation for how mathematical reasoning informs problem solving, inference, and precise communication in biology and enhance the diversity of quantitative biology education.  相似文献   

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We have designed, developed, and validated a 17-question Meiosis Concept Inventory (Meiosis CI) to diagnose student misconceptions on meiosis, which is a fundamental concept in genetics. We targeted large introductory biology and genetics courses and used published methodology for question development, which included the validation of questions by student interviews (n = 28), in-class testing of the questions by students (n = 193), and expert (n = 8) consensus on the correct answers. Our item analysis showed that the questions’ difficulty and discrimination indices were in agreement with published recommended standards and discriminated effectively between high- and low-scoring students. We foresee other institutions using the Meiosis CI as both a diagnostic tool and an instrument to assess teaching effectiveness and student progress, and invite instructors to visit http://q4b.biology.ubc.ca for more information.  相似文献   

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The curriculum decision‐making perceptions of a pilot sample of 75 American kindergarten through twelfth grade teachers doing graduate work in education were surveyed with a 42 item questionnaire. The first four questions established the demographics of the respondents and the next three items indicated that Americans feel more constrained in making curriculum decisions than their British counterparts. The cross‐cultural comparisons are based on the findings of Doherty & Travers (1984).

The final 35 items, adapted from the instrument developed by Doherty & Travers, were subject to a factor analysis. Five interpretable factors were extracted.

The factors were labelled (1) External Monitory, (2) External Professional, (3) Internal Professional, (4) Facilitative‐Constraining, and (5) Internal Professional Peers. These factors represented 32 items with three items unassignable to any factors. Interitem reliability of the factors was judged good. Though the British study also extracted five factors (from a 30 item pool), dissimilarities in labelling and ranking importance occurred. Some of the key differences were traced to the structure of the American educational setting.  相似文献   


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As the limitations of one‐off and disconnected professional learning programs for teachers are recognised, there is widespread interest in building learning communities and professional learning teams within schools. When considering how to build local learning communities, school and university partnerships are seen as offering rich possibilities for transformative professional action. Set in the context of the international agenda of “Education For All” (UNESCO, 2005 UNESCO. (2005). Education for all: Global monitoring project. Retrieved January 8, 2007, from http://portal.unesco.org/education/en/ev.php‐URL_ID=36004&URL_DO=DO_TOPIC&URL_SECTION=201.html (http://portal.unesco.org/education/en/ev.php-URL_ID=36004&URL_DO=DO_TOPIC&URL_SECTION=201.html)  [Google Scholar]) a model of sustained on‐going professional learning, developed in one large secondary school in Australia, is analysed. The social practices that generate action and participation for partnership members are then scrutinised for the legitimacy of school‐university partnerships and the contribution to enhancing teacher learning.  相似文献   

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“It takes a lot of courage to release the familiar and seemingly secure, to embrace the new. But there is no real security in what is no longer meaningful. There is more security in the adventurous and exciting, for in movement there is life, and in change there is power.”Alan Cohen (Used by permission. All rights reserved. For more information on Alan Cohen''s books and programs, see (www.alancohen.com.)
With the support of the East Tennessee State University (ETSU) administration and a grant from Howard Hughes Medical Institute, the departments of Biological Sciences, Mathematics and Statistics, and Curriculum and Instruction have developed a biology–math integrated curriculum. An interdisciplinary faculty team, charged with teaching the 18 curriculum modules, designed this three-semester curriculum, known as SYMBIOSIS. This curriculum was piloted to two student cohorts during the developmental stage. The positive feedback and assessment results of this project have given us the foundation to implement the SYMBIOSIS curriculum as a replacement for the standard biology majors curriculum at the introductory level. This article addresses the history and development of the curriculum, previous assessment results and current assessment protocol, and the future of ETSU''s approach to implementing the SYMBIOSIS curriculum.  相似文献   

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The current article represents a methodological proposal. It seeks to address the question of how one might recognize a discovery as a discovery without knowing in advance what is available to be discovered. We propose a solution and demonstrate it using data from a study previously reported by J. Roschelle (1992) Roschelle, J. 1992. Learning by collaborating: Convergent conceptual change. Journal of the Learning Sciences, 2: 235276. [Taylor & Francis Online] [Google Scholar]. Roschelle investigated 2 students' developing understandings of certain abstract features of Newtonian mechanics while working within a computer-based microworld, the Envisioning Machine. We employ an approach we term discovery as occasioned production to reexamine his data. Such an approach proceeds stepwise from the identification of some matter discovered, working backward to see just where that matter entered the conversation and then, finally, tracing from that point forward to illuminate how the proposal for a possible discovery was ultimately transformed into a discovery achieved. The notion of “evident vagueness,” borrowed from H. Garfinkel, M. Lynch, and D. Livingston's (1981) Garfinkel, H., Lynch, M. and Livingston, D. 1981. The work of discovering science construed with materials from the optically discovered pulsar. Philosophy of Social Science, 11: 131158. [Crossref], [Web of Science ®] [Google Scholar] account of the discovery of an optical pulsar, emerges as an important feature of our analysis. Following H. Garfinkel (2002) Garfinkel, H. 2002. Ethnomethodology's program: Working out Durkheim's aphorism. Lanham, MD: Rowman & Littlefield..  [Google Scholar], we present our findings as a “tutorial problem” and offer a suggestion for how a program of practice studies in the learning sciences might be pursued.  相似文献   

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This paper explores the social justice implications of two, ‘linked’, governance developments which have been instrumental in reshaping many education systems throughout the world: the ‘privatising’ and ‘globalising’ of education (Klees, Stromquist, & Samoff, 2012 Klees, S., Stromquist, N. and Samoff, J., eds. 2012. A critical review of the World Bank’s education strategy 2020, Rotterdam: Sense Publishers.  [Google Scholar]). We argue that such education governance innovations demand an explicit engagement with social justice theories, both in themselves, and as offering an opportunity to address issues of social justice that go beyond the re/distribution of education inputs and outputs, important though these are, and which take account of the political and accountability issues raised by globalising of education governance activity. To do this we draw upon Iris Marion Young’s concept of ‘the basic structure’ and her ‘social connection model’ of responsibility (Young, 2006 Young, I. M. 2006. Taking the basic structure seriously. Perspectives in Politics, 4: 9197. [Crossref] [Google Scholar]a,b) to develop a relational account of justice in education governance frameworks.  相似文献   

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This feature is designed to point CBE—Life Sciences Education readers to current articles of interest in life sciences education as well as more general and noteworthy publications in education research.This feature is designed to point CBE—Life Sciences Education readers to current articles of interest in life sciences education as well as more general and noteworthy publications in education research. URLs are provided for the abstracts or full text of articles. For articles listed as “Abstract available,” full text may be accessible at the indicated URL for readers whose institutions subscribe to the corresponding journal.1. Bush SD, Pelaez NJ, Rudd JA, Stevens MT, Tanner KD, Williams KS (2013). Widespread distribution and unexpected variation among science faculty with education specialties (SFES) across the United States. Proc Natl Acad Sci USA 110, 7170–7175.[Available at: www.pnas.org/content/110/18/7170.full.pdf+html?sid=f2823860-1fef-422c-b861-adfe8d82cef5]College and university basic science departments are taking an increasingly active role in innovating and improving science education and are hiring science faculty with education specialties (SFES) to reflect this emphasis. This paper describes a nationwide survey of these faculty at private and public degree-granting institutions. The authors assert that this is the first such analysis undertaken, despite the apparent importance of SFES at many, if not most, higher education institutions. It expands on earlier work summarizing survey results from SFES used in the California state university system (Bush et al., 2011 ).The methods incorporated a nationwide outreach that invited self-identified SFES to complete an anonymous, online survey. SFES are described as those “specifically hired in science departments to specialize in science education beyond typical faculty teaching duties” or “who have transitioned after their initial hire to a role as a faculty member focused on issues in science education beyond typical faculty teaching duties.” Two hundred eighty-nine individuals representing all major types of institutions of higher education completed the 95-question, face-validated instrument. Slightly more than half were female (52.9%), and 95.5% were white. There is extensive supporting information, including the survey instrument, appended to the article.Key findings are multiple. First, but not surprisingly, SFES are a national, widespread, and growing phenomenon. About half were hired since the year 2000 (the survey was completed in 2011). Interestingly, although 72.7% were in tenured or tenure-track positions, most did not have tenure before adopting SFES roles, suggesting that such roles are not, by themselves, an impediment to achieving tenure. A second key finding was that SFES differed significantly more between institutional types than between science disciplines. For example, SFES respondents at PhD-granting institutions were less likely to occupy tenure-track positions than those at MS-granting institutions and primarily undergraduate institutions (PUIs). Also, SFES at PhD institutions reported spending more time on teaching and less on research than their non-SFES peers. This may be influenced, of course, by the probability that fewer faculty at MS and PUI institutions have research as a core responsibility. The pattern is complex, however, because all SFES at all types of institutions listed teaching, service, and research as professional activities. SFES did report that they were much more heavily engaged in service activities than their non-SFES peers across all three types of institutions. A significantly higher proportion of SFES respondents at MS-granting institutions had formal science education training (60.9%), as compared with those at PhD-granting institutions (39.3%) or PUIs (34.8%).A third finding dealt with success of SFES in obtaining funding for science education research, with funding success defined as cumulatively obtaining $100,000 or more in their current positions. Interestingly, the factors that most strongly correlated statistically with funding success were 1) occupying a tenure-track position, 2) employment at a PhD-granting institution, and 3) having also obtained funding for basic science research. Not correlated were disciplinary field and, surprisingly, formal science education training.Noting that MS-granting institutions show the highest proportions of SFES who are tenured or tenure-track, who are higher ranked, who are trained in science education, and who have professional expectations aligned with those of their non-SFES peers, the authors suggest that these institutions are in the vanguard of developing science education as an independent discipline, similar to ecology or organic chemistry. They also point out that SFES at PhD institutions appear to be a different subset, occupying primarily non–tenure track, teaching positions. To the extent that more science education research funding is being awarded to these latter SFES, who occupy less enfranchised roles within their departments, the authors suggest the possibility that such funding may not substantially improve science education at these institutions. However, the authors make it clear that the implications of their findings merit more careful examination and discussion.2. Opfer JE, Nehm RH, Ha M (2012). Cognitive foundations for science assessment design: knowing what students know about evolution. J Res Sci Teach 49, 744–777.[Abstract available: http://onlinelibrary.wiley.com/doi/10.1002/tea.21028/abstract]The authors previously published an article (Nehm et al., 2012) documenting a new instrument (more specifically, a short-answer diagnostic test), Assessing Contextual Reasoning about Natural Selection (ACORNS). This article describes how cognitive principles were used in designing the theoretical framework of ACORNS. In particular, the authors attempted to follow up on the premise of a National Research Council (2001) report on educational assessment that use of research-based, cognitive models for student learning could improve the design of items used to measure students’ conceptual understandings.In applying this recommendation to design of the ACORNS, the authors were guided by four principles for assessing the progression from novice to expert in using core concepts of natural selection to explain and discuss the process of evolutionary change. The items in ACORNS are designed to assess whether, in moving toward expertise, individuals 1) use core concepts for facilitation of long-term recall; 2) continue to hold naïve ideas coexistent with more scientifically normative ones; 3) offer explanations centered around mechanistic rather than teleological causes; and 4) can use generalizations (abstract knowledge) to guide reasoning, rather than focusing on specifics or less-relevant surface features. Thus, these items prioritize recall over recognition, detect students’ use of causal features of natural selection, test for coexistence of normative and naïve conceptions, and assess students’ focus on surface features when offering explanations.The paper provides an illustrative set of four sample items, each of which describes an evolutionary change scenario with different surface features (familiar vs. unfamiliar taxa; plants vs. animals) and then prompts respondents to write explanations for how the change occurred. To evaluate the ability of items to detect gradations in expertise, the authors enlisted the participation of 320 students enrolled in an introductory biology sequence. Students’ written explanations for each of the four items were independently coded by two expert scorers for presence of core concepts and cognitive biases (deviations from scientifically normative ideas and causal reasoning). Indices were calculated to determine the frequency, diversity, and coherence of students’ concept usage. The authors also compared the students’ grades in a subsequent evolutionary biology course to determine whether the use of core concepts and cognitive biases in their ACORNS explanations could successfully predict future performance.Evidence from these qualitative and quantitative data analyses argued that the items were consistent with the cognitive model and four guiding principles used in their design, and that the assessment could successfully predict students’ level of academic achievement in subsequent study of evolutionary biology. The authors conclude by offering examples of student explanations to highlight the utility of this cognitive model for designing assessment items that document students’ progress toward expertise.3. Sampson V, Enderle P, Grooms J (2013). Development and initial validation of the Beliefs about Reformed Science Teaching and Learning (BARSTL) questionnaire. School Sci Math 113, 3–15.[Available: http://onlinelibrary.wiley.com/doi/10.1111/j.1949-8594.2013.00175.x/full]The authors report on the development of a Beliefs about Reformed Science Teaching and Learning (BARSTL) instrument (questionnaire), designed to map teachers’ beliefs along a continuum from traditional to reform-minded. The authors define reformed views of science teaching and learning as being those that are consistent with constructivist philosophies. That is, as quoted from Driver et al. (1994 , p. 5), views that stem from the basic assumption that “knowledge is not transmitted directly from one knower to another, but is actively built up by the learner” by adjusting current understandings (and associated rules and mental models) to accommodate and make sense of new information and experiences.The basic premise for the instrument development posed by the authors is that teachers’ beliefs about the nature of science and of the teaching and learning of science serve as a filter for, and thus strongly influence how they enact, reform-based curricula in their classrooms. They cite a study from a high school physics setting (Feldman, 2002 ) to illustrate the impact that teachers’ differing beliefs can have on the ways in which they incorporate the same reform-based curriculum into their courses. They contend that, because educational reform efforts “privilege” constructivist views of teaching and learning, the BARSTL instrument could inform design of teacher education and professional development by monitoring the extent to which the experiences they offer are effective in shifting teachers’ beliefs toward the more constructivist end of the continuum.The BARTSL questionnaire described in the article has four subscales, with eight items per subscale. The four subscales are: a) how people learn about science; b) lesson design and implementation; c) characteristics of teachers and the learning environment; and d) the nature of the science curriculum. In each subscale, four of the items were designed to be aligned with reformed perspectives on science teaching and learning, and four to have a traditional perspective. Respondents indicate the extent to which they agree with the item statements on a 4-point Likert scale. In scoring the responses, strong agreement with a reform-based item is assigned a score of 4 and strong disagreement a score of 1; scores for traditional items were assigned on a reverse scale (e.g., 1 for strong agreement). A more extensive characterization of the subscales is provided in the article, along with all of the instrument items (see Appendix).The article describes the seven-step process and associated analyses used to, in the words of the authors, “assess the degree to which the BARTSL instrument has accurately translated the construct, reformed beliefs about science teaching, into an operationalization.” The steps include: 1) defining the specific constructs (concepts that can be used to explain related phenomena) that the instrument would measure; 2) developing instrument items; 3) evaluating items for clarity and comprehensibility; 4) evaluating construct and content validity of the items and subscales; 5) a first round of evaluation of the instrument; 6) item and instrument revision; and 7) a second evaluation of validity and reliability (the extent to which the instrument yields the same results on repetition). Step 3 was accomplished by science education doctoral students who reviewed the items and provided feedback, and step 4 with assistance from a seven-person panel composed of science education faculty and doctoral students. Administration of the instrument to 104 elementary teacher education majors (ETEs) enrolled in a teaching method course was used to evaluate the first draft of the instrument and identify items for inclusion in the final instrument. The instrument was administered to a separate population of 146 ETEs in step 7.The authors used two estimates of internal consistency, a Spearman-Brown corrected correlation and coefficient alpha, to assess the reliability of the instrument; the resulting values were 0.80 and 0.77, respectively, interpreted as being indicative of satisfactory internal consistency. Content validity, defined by the authors as the degree to which the sample of items measures what the instrument was designed to measure, was assessed by a panel of experts who reviewed the items within each of the four subscales. The experts concluded that items that were designed to be consistent with reformed and traditional perspectives were in fact consistent and were evenly distributed throughout the instrument. To evaluate construct validity (which was defined as the instrument''s “theoretical integrity”), the authors performed a correlation analysis on the four subscales to examine the extent to which each could predict the final overall score on the instrument and thus be viewed as a single construct of reformed beliefs. They found that each of the subscales was a good predictor of overall score. Finally, they performed an exploratory factor analysis and additional follow-up analyses to determine whether the four subscales measure four dimensions of reformed beliefs and to ensure that items were appropriately distributed among the subscales. In general, the authors contend that the results of these analyses indicated good content and construct validity.The authors conclude by pointing out that BARTSL scores could be used for quantitative comparisons of teachers’ beliefs and stances about reform-minded science teaching and learning and for following changes over time. However, they recommend BARTSL scores not be used to infer a given level of reform-mindedness and are best used in combination with other data-collection techniques, such as observations and interviews.4. Meredith DC, Bolker JA (2012). Rounding off the cow: challenges and successes in an interdisciplinary physics course for life sciences students. Am J Phys 80, 913–922.[Abstract available at: http://ajp.aapt.org/resource/1/ajpias/v80/i10/p913_s1?isAuthorized=no]There is a well-recognized need to rethink and reform the way physics is taught to students in the life sciences, to evaluate those efforts, and to communicate the results to the education community. This paper describes a multiyear effort at the University of New Hampshire by faculties in physics and biological sciences to transform an introductory physics course populated mainly by biology students into an explicitly interdisciplinary course designed to meet students’ needs.The context was that of a large-enrollment (250–320 students), two-semester Introductory Physics for Life Science Students (IPLS) course; students attend one of two lecture sections that meet three times per week and one laboratory session per week. The IPLS course was developed and cotaught by the authors, with a goal of having “students understand how and why physics is important to biology at levels from ecology and evolution through organismal form and function, to instrumentation.” The selection of topics was drastically modified from that of a traditional physics course, with some time-honored topics omitted or de-emphasized (e.g., projectile motion, relativity), and others thought to be more relevant to biology introduced or emphasized (e.g., fluids, dynamics). In addition, several themes not always emphasized in a traditional physics course but important in understanding life processes were woven through the IPLS course: scaling, estimation, and gradient-driven flows.It is well recognized that life sciences students need to strengthen their quantitative reasoning skills. To address their students’ needs in this area, the instructors ensured that online tutorials were available to students, mathematical proofs that the students are not expected use were de-emphasized, and Modeling Instruction labs were incorporated that require students to model their own data with an equation and compose a verbal link between their equations and the physical world.Student learning outcomes were assessed through the use of the Colorado Learning Attitudes about Science Survey (CLASS), which measures students’ personal epistemologies of science by their responses on a Likert-scale survey. These data were supplemented by locally developed, open-ended surveys and Likert-scale surveys to gauge students’ appreciation for the role of physics in biology. Students’ conceptual understanding was evaluated using the Force and Motion Concept Evaluation (FCME) and Test of Understanding Graphs in Kinematics (TUG-K), as well as locally developed, open-ended physics problems that probed students’ understanding in the context of biology-relevant applications and whether their understanding of physics was evident in their use of mathematics.The results broadly supported the efficacy of the authors’ approaches in many respects. More than 80% of the students very strongly or strongly agreed with the statement “I found the biological applications interesting,” and almost 60% of the students very strongly or strongly agreed with the statements “I found the biological applications relevant to my other courses and/or my planned career” and “I found the biological applications helped me understand the physics.” Students were also broadly able to integrate physics into their understanding of living systems. Examples of questions that students addressed include one that asked students to evaluate the forces on animals living in water versus those on land. Ninety-one percent of the students were able to describe at least one key difference between motion in air and water. Gains in the TUG-K score averaged 33.5% across the 4 yr of the course offering and were consistent across items. However, the positive attitudes about biology applications in physics were not associated with gains in areas of conceptual understanding measured by the FCME instrument. These gains were more mixed than those from the TUG-K and dependent on the concept being evaluated, with values as low as 15% for some concepts and an average gain on all items of 24%. Overall, the gains on the two instruments designed to measure physics understanding were described by the authors as being “modest at best,” particularly in the case of the FCME, given that reported national averages for reformed courses for this instrument range from 33 to 93%.The authors summarize by identifying considerations they think are essential to design and implementation of a IPLS-like course: 1) the need to streamline the coverage of course topics to emphasize those that are truly aligned with the needs of life sciences majors; 2) the importance of drawing from the research literature for evidence-based strategies to motivate students and aid in their development of problem-solving skills; 3) taking the time to foster collaborations with biologists who will reinforce the physics principles in their teaching of biology courses; and 4) considering the potential constraints and limitations to teaching across disciplinary boundaries and beginning to strategize ways around them and build models for sustainability. The irony of this last recommendation is that the authors report having suspended the teaching of IPLS at their institution due to resource constraints. They recommend that institutions claiming to value interdisciplinary collaboration need to find innovative ways to reward and acknowledge such collaborations, because “external calls for change resonate with our own conviction that we can do better than the traditional introductory course to help life science students learn and appreciate physics.”I invite readers to suggest current themes or articles of interest in life science education, as well as influential papers published in the more distant past or in the broader field of education research, to be featured in Current Insights. Please send any suggestions to Deborah Allen (ude.ledu@nellaed).  相似文献   

15.
In a recent Journal of Early Childhood Teacher Education article, the author reported on a single case of a successful mentor–beginning teacher pairing that was derived from a larger qualitative study (Certo, 2005 Certo, J. 2005. Support, challenge, and the two-way street: Perceptions of a beginning second grade teacher and her quality mentor. Journal of Early Childhood Teacher Education, 26(1): 321. [CSA][Taylor & Francis Online] [Google Scholar]). The purpose of this article is to report findings from that larger investigation. Three Virginia elementary 1st-year teachers and their mentors were interviewed in September, December, and February. Beginning teachers also kept journals of reflections about challenges in 1st-year teaching and the presence, nature, and impact of mentoring activities. Perceptions of mentor activities and the perceived impact on beginning teachers’ thinking and professional development are described using Daloz’s support and challenge model (1988) Daloz, L. 1988. The story of Gladys who refused to grow: A morality tale for mentors. Lifelong Learning, 11(4): 47. [CSA] [Google Scholar]. Mentors provided a balance of support and challenge activities, and beginning teachers reported being impacted by their mentors in numerous ways, from classroom management to adoption of new instructional approaches. These cases may be useful to practitioners as models of effective practice.  相似文献   

16.
What role should pleasure play in kinesiology? Although pleasure is an important concept in kinesiology, the strengths, weaknesses, and dangers of this concept have not been properly clarified. Douglas Booth and Richard Pringle have both recently scolded kinesiologists over the issue of pleasure in kinesiology with decidedly mixed results. They insist that the importance of pleasure has been neglected, and that the role that human culture plays in properly understanding pleasure in kinesiology, has been underestimated. Booth (2009) Booth, D. 2009. Pleasure and physical education philosophy. Quest, 61(2): 133153. [Taylor & Francis Online], [Web of Science ®] [Google Scholar] argues that “puritanical” prohibitions have made pleasure suspect. Pringle (2010) Pringle, R. 2010. The educative value of positive movement affects. Quest, 62(2): 119134. [Taylor & Francis Online], [Web of Science ®] [Google Scholar] argues that kinesiologists must remember that “many students are not currently gaining a love for movement in their [physical education] experiences” (p. 130). Each scholar's suspicion of traditional distinctions between “good and bad physical pleasures” (Booth, 2009 Booth, D. 2009. Pleasure and physical education philosophy. Quest, 61(2): 133153. [Taylor & Francis Online], [Web of Science ®] [Google Scholar], p. 148) results in an untenable commitment to pleasure as an intrinsic good. In short, their views are hedonistic. Although Booth and Pringle are right that pleasure is good, it is not an end in itself.  相似文献   

17.
A motor task that requires fine control of upper limb movements and a cognitive task that requires executive processing—first performing them separately and then concurrently—was performed by 18 young and 18 older adults. The motor task required participants to tap alternatively on two targets, the sizes of which varied systematically. The cognitive task required participants to generate a series of random numbers at fixed production rates. Participants' performance on the motor task decreased slightly from single- to concurrent-task condition, and the dual-task cost was age-independent. Older adults showed large cognitive dual-task costs as motor-control demands increased. Younger adults' cognitive performance was not affected by concurrent task demands. These results are discussed in light of the permeation model developed by Baltes and Lindenberger (1997 Baltes , P. B. & Lindenberger , U. ( 1997 ). Emergence of a powerful connection between sensory and cognitive functions across the adult life span: A new window to the study of cognitive aging? Psychology and Aging , 12 ( 1 ), 1221 . [INFOTRIEVE] [CSA] [CROSSREF] [Crossref], [PubMed], [Web of Science ®] [Google Scholar]). Practical implications and educational recommendations are presented.  相似文献   

18.
Background: For the past decade, science educators have been exploring the use of Socio-scientific Issues (SSI) as contexts for science teaching and learning, and research indicates that doing so can support significant learning gains. However, research related to how teachers take up the practice of SSI-based instruction is far more limited, due in part to a lack of tools for use in this kind of research.

Purpose: The focus of this research is development and testing of a new classroom observation protocol specifically designed for SSI-based instructional contexts.

Design and methods: Development of this SSI-Observation Protocol (SSI-OP) took place in four distinct phases: review of existing protocols and SSI-based instruction frameworks, writing and revision of protocol items, initial testing of the draft protocol, and soliciting feedback from SSI experts.

Sample: Following the four stages of SSI-OP development, we progressed to a series of field tests. The field tests were conducted with three different samples. The first sample was an experienced (10 + years) high school biology teacher and one of her honors biology classes. The second sample consisted of seven Turkish Pre-service Science Teachers (PST) participating in a science methods course. The third sample included two Thai PST from a field experience course embedded within a teacher education program.

Results: The final version of the protocol addressed five dimensions of SSI-based instructional activities: focus of instruction, teaching moves, role of teacher, role of students, and classroom environment.

Conclusions: The SSI-OP could be used in a variety of ways for research including documentation of current practices, impacts of professional development and/or curricula on teaching practices, and changes in teaching over time. We offer the SSI-OP as a new tool with the potential to contribute to science teacher education and research that may advance the teaching and learning of science through SSI.  相似文献   


19.
Tanzania, like many other African countries, has experienced a rapid expansion of its secondary education sector. This has resulted in large numbers of secondary school graduates struggling to build a future through continuing education or finding employment. 1 1. During the past decade, secondary education enrolment in Tanzania has increased rapidly, net enrolment in secondary education in 2009 being 31.3% (URT 2009 United Republic of Tanzania (URT). 2009. Basic education statistics in Tanzania. National data. Dar es Salaam: The Ministry of Education and Vocational Training. http://216.15.191.173/statistics.html.  [Google Scholar]). Still, transition rates from primary to secondary education are among the lowest in Sub-Saharan Africa. Although almost equal in lower years of primary education, the proportion and performance of girls decrease while moving to the upper secondary education. For a recent review on gender and education in Tanzania, see Okkolin, Lehtomäki, and Bhalalusesa (2010 Okkolin, M.-A., Lehtomäki, E. and Bhalalusesa, E. 2010. Successes and challenges in the education sector development in Tanzania: Focus on gender and inclusive education. Gender and Education, 22(1): 6371. [Taylor & Francis Online], [Web of Science ®] [Google Scholar]). Students are faced with the difficult task of assessing their opportunities in the face of various challenges and making plans to build a better life. The presented research uses empathy-based stories to identify which elements were considered to be important by students in determining their success in education. The analysis of narrative data represents a shared cultural meaning on the social and cultural support available to students. The findings suggest that using empathy-based stories as a methodological tool can provide valuable insights for culture-sensitive and intercultural research through its ability to widen the context of discovery.  相似文献   

20.
This paper draws on data collected in a one‐year research project focusing on elucidating theory/practice relations in learning to teach. As a teacher educator I grapple with the nature and role of teaching methodology. The notion of method, with its implied order and certainty, is confronted alongside prospective teachers throughout their coursework and student‐teaching experiences. Reflexivity is considered essential to this research process, providing a means to address the interface between the empirical data collected alongside student‐teachers and its interpretations. In this regard I draw on the historical writings of Dewey (1904 Dewey J (1904) The relation of theory and practice in education in: C. A. McMurry (Ed.) The relation of theory to practice in the education of teachers: the third yearbook of the National Society for the Scientific Study of Education (Chicago, IL, University of Chicago Press) 9 30  [Google Scholar], 1910 Dewey J (1910) How we think (Boston, MA, Heath) [Crossref] [Google Scholar], 1938 Dewey J (1938) Experience and education (New York, Collier Books) [Taylor & Francis Online] [Google Scholar]) and Bakhtin (1990 Bakhtin MM (1990) Art and answerability (Austin, TX, University of Texas Press)  [Google Scholar], 1993 Bakhtin MM (1993) Toward a philosophy of the act (Austin, TX, University of Texas Press)  [Google Scholar]), found to provide insights into theory/practice relations. Through Dewey's thinking, bearings are retrieved that reorient teaching/learning methodology toward neglected needs and opportunities in learning to teach. Through Bakhtin's early aesthetic essays, a language is retrieved that addresses forgotten assumptions central to reformulating teaching methodology. This paper pursues the necessary character of a teacher preparation course fostering a mode of method that is radically different from the technical one. It is a mode of method that attends to the voices of prospective teachers in schools confronting the nature of learners and learning, teachers and teaching. It is a mode of method that reminds all involved in the schooling process of the power of teaching/learning restored to its participatory and complex nature.  相似文献   

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