共查询到20条相似文献，搜索用时 468 毫秒
1.
James J. Smith Kendra Spence Cheruvelil Stacie Auvenshine 《CBE life sciences education》2013,12(3):542-552
Phylogenetic trees provide visual representations of ancestor–descendant relationships, a core concept of evolutionary theory. We introduced “tree thinking” into our introductory organismal biology course (freshman/sophomore majors) to help teach organismal diversity within an evolutionary framework. Our instructional strategy consisted of designing and implementing a set of experiences to help students learn to read, interpret, and manipulate phylogenetic trees, with a particular emphasis on using data to evaluate alternative phylogenetic hypotheses (trees). To assess the outcomes of these learning experiences, we designed and implemented a Phylogeny Assessment Tool (PhAT), an open-ended response instrument that asked students to: 1) map characters on phylogenetic trees; 2) apply an objective criterion to decide which of two trees (alternative hypotheses) is “better”; and 3) demonstrate understanding of phylogenetic trees as depictions of ancestor–descendant relationships. A pre–post test design was used with the PhAT to collect data from students in two consecutive Fall semesters. Students in both semesters made significant gains in their abilities to map characters onto phylogenetic trees and to choose between two alternative hypotheses of relationship (trees) by applying the principle of parsimony (Occam''s razor). However, learning gains were much lower in the area of student interpretation of phylogenetic trees as representations of ancestor–descendant relationships. 相似文献
2.
This paper describes a newly adapted instrument for measuring novice-to-expert-like perceptions about biology: the Colorado Learning Attitudes about Science Survey for Biology (CLASS-Bio). Consisting of 31 Likert-scale statements, CLASS-Bio probes a range of perceptions that vary between experts and novices, including enjoyment of the discipline, propensity to make connections to the real world, recognition of conceptual connections underlying knowledge, and problem-solving strategies. CLASS-Bio has been tested for response validity with both undergraduate students and experts (biology PhDs), allowing student responses to be directly compared with a consensus expert response. Use of CLASS-Bio to date suggests that introductory biology courses have the same challenges as introductory physics and chemistry courses: namely, students shift toward more novice-like perceptions following instruction. However, students in upper-division biology courses do not show the same novice-like shifts. CLASS-Bio can also be paired with other assessments to: 1) examine how student perceptions impact learning and conceptual understanding of biology, and 2) assess and evaluate how pedagogical techniques help students develop both expertise in problem solving and an expert-like appreciation of the nature of biology. 相似文献
3.
Experts are more proficient in manipulating and translating between multiple representations (MRs) of a given concept than novices. Studies have shown that instruction using MR can increase student understanding of MR, and one model for MR instruction in chemistry is the chemistry triplet proposed by Johnstone. Concreteness fading theory suggests that presenting concrete representations before abstract representations can increase the effectiveness of MR instruction; however, little work has been conducted on varying the order of different representations during instruction and the role of concreteness in assessment. In this study, we investigated the application of concreteness fading to MR instruction and assessment in teaching chemistry. In two experiments, undergraduate students in either introductory psychology courses or general chemistry courses were given MR instruction on phase changes using different orders of presentation and MR assessment questions based on the representations in the chemistry triplet. Our findings indicate that the order of presentation based on levels of concreteness in MR chemistry instruction is less important than implementation of comprehensive MR assessments. Even after MR instruction, students display an asymmetric understanding of the chemical phenomenon on the MR assessments. Greater emphasis on MR assessments may be an important component in MR instruction that effectively moves novices toward more expert MR understanding. 相似文献
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Elena Bray Speth Neil Shaw Jennifer Momsen Adam Reinagel Paul Le Ranya Taqieddin Tammy Long 《CBE life sciences education》2014,13(3):529-539
Mutation is the key molecular mechanism generating phenotypic variation, which is the basis for evolution. In an introductory biology course, we used a model-based pedagogy that enabled students to integrate their understanding of genetics and evolution within multiple case studies. We used student-generated conceptual models to assess understanding of the origin of variation. By midterm, only a small percentage of students articulated complete and accurate representations of the origin of variation in their models. Targeted feedback was offered through activities requiring students to critically evaluate peers’ models. At semester''s end, a substantial proportion of students significantly improved their representation of how variation arises (though one-third still did not include mutation in their models). Students’ written explanations of the origin of variation were mostly consistent with their models, although less effective than models in conveying mechanistic reasoning. This study contributes evidence that articulating the genetic origin of variation is particularly challenging for learners and may require multiple cycles of instruction, assessment, and feedback. To support meaningful learning of the origin of variation, we advocate instruction that explicitly integrates multiple scales of biological organization, assessment that promotes and reveals mechanistic and causal reasoning, and practice with explanatory models with formative feedback. 相似文献
7.
F. Collin Hobbs Daniel J. Johnson Katherine D. Kearns 《CBE life sciences education》2013,12(4):676-686
One goal of postsecondary education is to assist students in developing expert-level understanding. Previous attempts to encourage expert-level understanding of phylogenetic analysis in college science classrooms have largely focused on isolated, or “one-shot,” in-class activities. Using a deliberate practice instructional approach, we designed a set of five assignments for a 300-level plant systematics course that incrementally introduces the concepts and skills used in phylogenetic analysis. In our assignments, students learned the process of constructing phylogenetic trees through a series of increasingly difficult tasks; thus, skill development served as a framework for building content knowledge. We present results from 5 yr of final exam scores, pre- and postconcept assessments, and student surveys to assess the impact of our new pedagogical materials on student performance related to constructing and interpreting phylogenetic trees. Students improved in their ability to interpret relationships within trees and improved in several aspects related to between-tree comparisons and tree construction skills. Student feedback indicated that most students believed our approach prepared them to engage in tree construction and gave them confidence in their abilities. Overall, our data confirm that instructional approaches implementing deliberate practice address student misconceptions, improve student experiences, and foster deeper understanding of difficult scientific concepts. 相似文献
8.
This study describes a lesson in which students engaged in inquiry in evolutionary biology in order to develop a better understanding of the concepts and reasoning skills necessary to support knowledge claims about changes in the genetic structure of populations, also known as microevolution. This paper describes how a software simulation called EVOLVE can be used to foster discussions about the conceptual knowledge used by advanced secondary or introductory college students when investigating the effects of natural selection on hypothetical populations over time. An experienced professor's use and rationale of a problem-based lesson using the simulation is examined. Examples of student misconceptions and naïve (incomplete) conceptions are described and an analysis of the procedural knowledge for experimenting with the computer model is provided. The results of this case study provide a model of how EVOLVE can be used to engage students in a complex problem-solving experience that encourages student meta-cognitive reflection about their understanding of evolution at the population level. Implications for teaching are provided and ways to improve student learning and problem solving in population genetics are suggested. 相似文献
9.
D. A. Donovan L. J. Atkins I. Y. Salter D. J. Gallagher R. F. Kratz J. V. Rousseau G. D. Nelson 《CBE life sciences education》2013,12(2):215-229
We report on the development of a life sciences curriculum, targeted to undergraduate students, which was modeled after a commercially available physics curriculum and based on aspects of how people learn. Our paper describes the collaborative development process and necessary modifications required to apply a physics pedagogical model in a life sciences context. While some approaches were easily adapted, others provided significant challenges. Among these challenges were: representations of energy, introducing definitions, the placement of Scientists’ Ideas, and the replicability of data. In modifying the curriculum to address these challenges, we have come to see them as speaking to deeper differences between the disciplines, namely that introductory physics—for example, Newton''s laws, magnetism, light—is a science of pairwise interaction, while introductory biology—for example, photosynthesis, evolution, cycling of matter in ecosystems—is a science of linked processes, and we suggest that this is how the two disciplines are presented in introductory classes. We illustrate this tension through an analysis of our adaptations of the physics curriculum for instruction on the cycling of matter and energy; we show that modifications of the physics curriculum to address the biological framework promotes strong gains in student understanding of these topics, as evidenced by analysis of student work. 相似文献
10.
We present a multiple-choice test, the Montana State University Formal Reasoning Test (FORT), to assess college students' scientific reasoning ability. The test defines scientific reasoning to be equivalent to formal operational reasoning. It contains 20 questions divided evenly among five types of problems: control of variables, hypothesis testing, correlational reasoning, proportional reasoning, and probability. The test development process included the drafting and psychometric analysis of 23 instruments related to formal operational reasoning. These instruments were administered to almost 10,000 students enrolled in introductory science courses at American universities. Questions with high discrimination were identified and assembled into an instrument that was intended to measure the reasoning ability of students across the entire spectrum of abilities in college science courses. We present four types of validity evidence for the FORT. (a) The test has a one-dimensional psychometric structure consistent with its design. (b) Test scores in an introductory biology course had an empirical reliability of 0.82. (c) Student interviews confirmed responses to the FORT were accurate indications of student thinking. (d) A regression analysis of student learning in an introductory biology course showed that scores on the FORT predicted how well students learned one of the most challenging concepts in biology, natural selection. 相似文献
11.
Zhong Ma Cynthia Cooper Hyun-Joo Kim Diane Janick-Buckner 《CBE life sciences education》2009,8(2):140-146
We describe a laboratory exercise developed for a cell biology course for second-year undergraduate biology majors. It was designed to introduce undergraduates to the basic molecular biology techniques of Western blotting and immunodetection coupled with the technique of tissue printing in detecting the presence, relative abundance, and distribution of ribulose-1,5-bisphosphate carboxylase in various plant materials. Pre- and postlab surveys indicated significant postlab gains in student understanding of all three lab techniques and relevant lecture topics. Additional postlab survey questions on student perception of the lab modules suggested that the laboratory exercises successfully met a series of pedagogical goals set by the instructors. The combination of these techniques provided a basis for quantitative and qualitative (visual) analysis of a biologically important enzyme and can be applied or modified readily to study other proteins and biological molecules in lab exercises for an introductory cell biology course or molecular biology course. 相似文献
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Three approaches to molecular phylogenetics are demonstrated to biology students as they explore molecular data from Homo sapiens and four related primates. By analyzing DNA sequences, protein sequences, and chromosomal maps, students are repeatedly challenged to develop hypotheses regarding the ancestry of the five species. Although these exercises were designed to supplement and enhance classroom instruction on phylogeny, cladistics, and systematics in the context of a postsecondary majors-level introductory biology course, the activities themselves require very little prior student exposure to these topics. Thus, they are well suited for students in a wide range of educational levels, including a biology class at the secondary level. In implementing this exercise, we have observed measurable gains, both in student comprehension of molecular phylogeny and in their acceptance of modern evolutionary theory. By engaging students in modern phylogenetic activities, these students better understood how biologists are currently using molecular data to develop a more complete picture of the shared ancestry of all living things. 相似文献
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Two studies examined student psychological need satisfaction as a predictor of positive teacher-course evaluations. In Study 1, 268 undergraduates recalled and rated the quality of a recent important college course, then rated their feelings of autonomy, competence, and relatedness within that course. Consistent with self-determination theory, all three ratings predicted instructor and/or course ratings. Study 2 found the same pattern in a sample of 179 introductory journalism students nested within 12 sections of a single course. Study 2 also evaluated instructor characteristics as predictors of mean levels of student need satisfaction across the 12 classes. Although instructor age and overall teaching experience were unrelated to students' need satisfaction, greater experience teaching their particular class negatively predicted student autonomy and relatedness need satisfaction. Implications for pedagogical practice are discussed. 相似文献
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University Modeling Instruction (UMI) is an approach to curriculum and pedagogy that focuses instruction on engaging students in building, validating, and deploying scientific models. Modeling Instruction has been successfully implemented in both high school and university physics courses. Studies within the physics education research (PER) community have identified UMI''s positive impacts on learning gains, equity, attitudinal shifts, and self-efficacy. While the success of this pedagogical approach has been recognized within the physics community, the use of models and modeling practices is still being developed for biology. Drawing from the existing research on UMI in physics, we describe the theoretical foundations of UMI and how UMI can be adapted to include an emphasis on models and modeling for undergraduate introductory biology courses. In particular, we discuss our ongoing work to develop a framework for the first semester of a two-semester introductory biology course sequence by identifying the essential basic models for an introductory biology course sequence. 相似文献
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Problem-solving behavior of six novice subjects attempting to solve an electrostatics problem in second-semester calculus-based college physics was observed and recorded. Five of the subjects were characterized as “A” or “B” students and one subject as a “D” student in introductory college physics. Although the A or B subjects were able to arrive at a “correct” solution to the problem, they exhibited major misconceptions about the problem situation as well as minimal qualitative understanding of the problem situation. The A or B subjects were successful in identifying, either from memory or written notes, equations relevant to electrostatics, whereas the D subject was not. The implication of this study is that current instruction in introductory calculus-based college physics and the students' previous science learnings place a premium on acquisition of correct quantitative solutions at the expense of qualitative understanding of physics problem situations. 相似文献
16.
Josephine A. Gasiewski M. Kevin Eagan Gina A. Garcia Sylvia Hurtado Mitchell J. Chang 《Research in higher education》2012,53(2):229-261
The lack of academic engagement in introductory science courses is considered by some to be a primary reason why students
switch out of science majors. This study employed a sequential, explanatory mixed methods approach to provide a richer understanding
of the relationship between student engagement and introductory science instruction. Quantitative survey data were drawn from
2,873 students within 73 introductory science, technology, engineering, and mathematics (STEM) courses across 15 colleges
and universities, and qualitative data were collected from 41 student focus groups at eight of these institutions. The findings
indicate that students tended to be more engaged in courses where the instructor consistently signaled an openness to student
questions and recognizes her/his role in helping students succeed. Likewise, students who reported feeling comfortable asking
questions in class, seeking out tutoring, attending supplemental instruction sessions, and collaborating with other students
in the course were also more likely to be engaged. Instructional implications for improving students’ levels of academic engagement
are discussed. 相似文献
17.
Grounded in teacher professional development addressing the intersection of student diversity and content area instruction, this study examined school teachers' pedagogical reasoning complexity as they reflected on their second language learners' science problem solving abilities using both home and school contexts. Teachers responded to interview questions after watching a video of one of their students engaged in a science problem solving task. Over a 5-year period, 206 teacher interviews were conducted with a total of 133 teachers. Results indicated significant differences across the dimensions of pedagogical reasoning complexity as teachers expressed both deficit and resource oriented thinking. 相似文献
18.
This study compared the effectiveness of collaborative group composition and instructional method on reasoning gains and achievement in college biology. Based on initial student reasoning ability (i.e., low, medium, or high), students were assigned to either homogeneous or heterogeneous collaborative groups within either inquiry or didactic instruction. Achievement and reasoning gains were assessed at the end of the semester. Inquiry instruction, as a whole, led to significantly greater gains in reasoning ability and achievement. Inquiry instruction also led to greater confidence and more positive attitudes toward collaboration. Low-reasoning students made significantly greater reasoning gains within inquiry instruction when grouped with other low reasoners than when grouped with either medium or high reasoners. Results are consistent with equilibration theory, supporting the idea that students benefit from the opportunity for self-regulation without the guidance or direction of a more capable peer. 相似文献
19.
Emine Adadan Karen E. Irving Kathy C. Trundle 《International Journal of Science Education》2013,35(13):1743-1775
This quasi‐experimental study examined 42 high school introductory chemistry students’ conceptual understandings of the particulate nature of matter (PNM) before and immediately after instruction. Two groups of students, who were taught by the same teacher, received one of two possible instructional interventions: Reform‐Based Teaching (RBT) or Reform‐Based Teaching with Multiple Representations (RBTw/MR). The RBTw/MR instruction differed from the RBT instruction in terms of the frequency of using multiple representations (visual, textual, oral) in relationship to the macroscopic phenomenon and the likely actions occurring at the submicroscopic level. Qualitative research methods, including open‐ended questionnaires and interviews, were used to investigate and describe participants’ conceptual understandings of the PNM over time. The findings indicated that before instruction all participants held a range of alternative conceptions about the aspects of the PNM. Post‐instruction findings indicate that the RBTw/MR instruction was more efficacious in promoting a scientific understanding of the PNM than was the instruction without multiple representations. 相似文献
20.
A large body of research has examined students' conceptions of evolution and their relationships to acceptance of evolution. Proficiency in statistical and probabilistic reasoning has long been considered to be an essential feature of evolutionary reasoning, yet almost no empirical work has explored these putative connections. The RaPro instruments have recently been developed to measure statistical reasoning in the contexts of mathematics (RaProMath) and evolution (RaProEvo). Our study provides additional validation of these instruments using Rasch analysis and quantifies the contribution of statistical reasoning to both understanding and accepting evolution. We recruited a large sample (N = 564) of undergraduate students enrolled in an introductory biology course at a large public research university in the United States. Students completed a suite of published instruments that assessed statistical reasoning, evolutionary understanding, and evolutionary acceptance. Our findings indicate that validity inferences derived from RaPro scores generalized to the new sample, and that proficiency in statistical reasoning explained 28% of the variance in evolutionary knowledge and 19% of the variation in evolutionary acceptance. The inclusion of demographic variables into the model significantly increased the explained variance in acceptance. Notably, the variance in evolution acceptance explained by statistical reasoning was comparable to that of thinking dispositions or evolutionary knowledge reported in the literature. This work provides the first large-scale evidence of the role of statistical reasoning in evolutionary knowledge and acceptance and motivates future work to explore how statistical literacy should be integrated into evolution education efforts. 相似文献