Biological Principles and Threshold Concepts for Understanding Natural Selection

Modern evolutionary theory is both a central theory and an integrative framework of the life sciences. This is reflected in the common references to evolution in modern science education curricula and contexts. In fact, evolution is a core idea that is supposed to support biology learning by facilitating the organization of relevant knowledge. In addition, evolution can function as a pivotal link between concepts and highlight similarities in the complexity of biological concepts. However, empirical studies in many countries have for decades identified deficiencies in students’ scientific understanding of evolution mainly focusing on natural selection. Clearly, there are major obstacles to learning natural selection, and we argue that to overcome them, it is essential to address explicitly the general abstract concepts that underlie the biological processes, e.g., randomness or probability. Hence, we propose a two-dimensional framework for analyzing and structuring teaching of natural selection. The first—purely biological—dimension embraces the three main principles variation, heredity, and selection structured in nine key concepts that form the core idea of natural selection. The second dimension encompasses four so-called thresholds, i.e., general abstract and/or non-perceptual concepts: randomness, probability, spatial scales, and temporal scales. We claim that both of these dimensions must be continuously considered, in tandem, when teaching evolution in order to allow development of a meaningful understanding of the process. Further, we suggest that making the thresholds tangible with the aid of appropriate kinds of visualizations will facilitate grasping of the threshold concepts, and thus, help learners to overcome the difficulties in understanding the central theory of life.     

The Right “Fit”: Exploring Science Teacher Candidates’ Approaches to Natural Selection Within a Clinical Simulation

Teachers and students struggle with the complexities surrounding the evolution of species and the process of natural selection. This article examines how science teacher candidates (STCs) engage in a clinical simulation that foregrounds two common challenges associated with natural selection—students’ understanding of “survival of the fittest” and the variation of species over time. We outline the medical education pedagogy of clinical simulations and its recent diffusion to teacher education. Then, we outline the study that situates each STC in a one-to-one interaction with a standardized student who is struggling to accurately interpret natural selection concepts. In simulation with the standardized student, each STC is challenged to recognize content misconceptions and respond with appropriate instructional strategies and accurate explanations. Findings and implications center on the STCs’ instructional practices in the simulation and the use of clinical learning environments to foster science teacher learning.     

Digital technology and caregiver training for older persons: Cognitive and affective perspectives

ABSTRACT

This research project included two studies that investigated (a) differences between technology use in tech-knowledgeable and less tech-knowledgeable older persons, (b) cognitive and affective variables and their association with the application of technology, and (c) the implications of these variables on the design of remote-delivered caregiver education. Study 1 findings suggested that high technology (e.g., Internet delivered education) reduced stress among the tech-knowledgeable group. In Study 2, which focused on the less tech-knowledgeable group, neither high technology (e.g., telehealth-delivered education) nor low technology (e.g., phone-delivered education) was associated with the cognitive and affective measures used in the study. Implications in the training of older caregivers with digital technology are discussed for negotiating the affective and cognitive features in remote delivered caregiver eduational protocols.     

Learning natural selection through computational thinking: Unplugged design of algorithmic explanations

Computational thinking (CT) is a way of making sense of the natural world and problem solving with computer science concepts and skills. Although CT and science integrations have been called for in the literature, empirical investigations of such integrations are lacking. Prior work in natural selection education indicates students struggle to explain natural selection in different contexts and natural selection misconceptions are common. In this mixed methods study, secondary honors biology students learn natural selection through CT by engaging in the design of unplugged algorithmic explanations. Students learned CT principles and practices and applied them to learn and explain the natural selection process. Algorithmic explanations were used to scaffold transfer of natural selection knowledge across contexts through investigation of three organisms and the creation of generalized natural selection algorithms. Students' pre- and post-unit algorithmic explanations of natural selection were analyzed to answer the following research questions: (a) How do students' conceptions of natural selection change over the course of a CT focused unit? (b) What is the relationship between CT and natural selection in students' algorithmic explanations? (c) What are students' perspectives of learning natural selection with CT? Results indicate students' conceptions of natural selection increased and natural selection misconceptions decreased over the course of the unit. Within their post-unit algorithmic explanations, students used specific CT principles in conjunction with natural selection concepts to explain natural selection, which helped them to learn the details of the natural selection process and correct their natural selection misconceptions. Students indicated the use of CT in unplugged algorithmic explanations in different contexts helped them learn natural selection. This study shows unplugged CT can be used to teach students science content, and it provides an example for further CT and science integrations. Implications for the field are discussed.     

Student Learning Theory goes (back) to (high) school

Biggs’ 3P (Presage–Process–Product) model, a key framework in Student Learning Theory, provides a powerful means of understanding relations between students’ perceptions of the teaching and learning environment, learning strategies, and learning outcomes. While influential in higher education, fewer tests of the model in secondary education contexts have been conducted. We investigated relations between Presage, Process and Product variables in the Australian secondary education context, using a wider range of Presage variables than is typical, as well as a novel set of outcomes (class participation, homework completion, and educational aspirations). Australian students (N = 5,198) from 13 high schools participated in the study, completing a paper-based survey in class. Confirmatory factor analysis was used to test for construct validity of scales. Structural equation modeling was used to determine the fit of the hypothesised 3P model to the data, and estimate direct and indirect effects between Presage, Process and Product variables. Across the Presage variables, academic self-efficacy and perceived teacher support had the strongest direct effects on outcome variables, as well as the strongest indirect effects through the Product variables. Demographic (e.g., age, gender, parental education) and personological (e.g., Big five personality measures) covariates were generally less salient. The present study illustrates the utility of the 3P model in contemporary secondary education settings. Building academic self-efficacy and positive perceptions of teacher support should enhance both the Processes and Products of learning in secondary settings.     

Students’ intuitive explanations of the causes of homologies and adaptations

This paper reports data from a study aiming to explore secondary students’ preconceptions and explanations about evolutionary processes. Students may exhibit both alternative and scientifically acceptable conceptions and bring different ones into play in response to different problem contexts. Hence, the examination of their explanations before instruction within different problem contexts is expected to highlight the concepts that instruction should put more emphasis on. To achieve this, an open-ended questionnaire in conjunction with semi-structured interviews was used to allow students to express their own views on issues related to evolution. Students’ explanations highlighted their lack of knowledge of important evolutionary concepts such as common descent and natural selection. In addition, many students explained the origin of traits as the result of evolution through need via purposeful change or as carefully designed adaptations. Rather than evolutionary, final causes formed the basis for the majority of students’ explanations. In many cases students provided different explanations for the same process to tasks with different content. It seems that the structure and the content of the task may have an effect on the explanations that students provide. Implications for evolution education are discussed and a minimal explanatory framework for evolution is suggested.     

The Influence of Education Major: How Diverse Preservice Teachers View Pseudoscience Topics

Pseudoscience beliefs (e.g., astrology, ghosts or UFOs) are rife in American society. Most research examines creation/evolution among liberal arts majors, general public adults, or, infrequently, middle or high school science teachers. Thus, research truncates the range of ersatz science thinking and the samples it studies. We examined diverse beliefs, e.g., extraterrestrials, magic, Biblical creation, and evolution, among 540 female and 123 male future teachers, including 325 elementary education majors. We study how these cognitions related to education major and, because popular media often present pseudoscience “information”, student media use. Future elementary educators most often rejected evolution and endorsed “creationism” or Intelligent Design. Education majors held similar beliefs about astrology, UFO landings, or magic. Compared with other education students, elementary education majors watched less news or science television and read fewer popular science magazines. However, religious and media variables explained more variation in creation/evolution beliefs than education major. We discuss implications of our findings for elementary school science education and how teacher educators may be able to affect pseudoscience beliefs among their elementary education students.     

A Critique of the Theoretical and Empirical Literature of the Use of Diagrams, Graphs, and Other Visual Aids in the Learning of Scientific-Technical Content from Expository Texts and Instruction

This article presents a critical review and analysis of key studies that have been done in science education and other areas on the effects and effectiveness of using diagrams, graphs, photographs, illustrations, and concept maps as adjunct visual aids in the learning of scientific-technical content. It also summarizes and reviews those studies that have students draw diagrams, graphs, maps, and charts to express their understandings of the concepts and relationships that are present in the text they read or/and empirical data provided (i.e., student-generated adjunct visual productions). In general, the research and theory on instructional aids is fragmented and somewhat unsystematic with several flaws and a number of key uncontrolled variables, which actually suppress and mask effects in the studies that have been done. The findings of these studies are compared to relevant literature and empirical research and findings in the areas of cognitive psychology, computer science, neuroscience, and artificial intelligence that help to clarify many of the inconsistencies, contradictions, and lack of effects found for visual (e.g., diagrams and graphs) instructional aids in the science education literature currently and in the past 20 years. A model and a set of criteria and goals for improving research in this area is then described, as visuals are a first step in the process of learning formal (scientific) models, which are most often visually represented. Understanding how students learn formal models is one the outstanding research challenges in the next 20 years, both within and outside of science education.     

IDEA: Identifying design principles in educational applets

The Internet is increasingly being used as a medium for educational software in the form of miniature applications (e.g., applets) to explore concepts in a domain. One such effort in mathematics education, the Educational Software Components of Tomorrow (ESCOT) project, created 42 miniature applications each consisting of a context, a set of questions, and one or more interactive applets to help students explore a mathematical concept. They were designed by experts in interface design, educational technology, and classroom teaching. However, some applications were more successful for fostering student problem-solving than others. This article describes the method used to mine a subset (25) of these applets for design principles that describe successful learner-centered design by drawing on such data as videos of students using the software and summaries of written student work. Twenty-one design principles were identified, falling into the categories of motivation, presentation, and support for problem solving. The main purpose of this article is to operationalize a method for post hoc extraction of design principles from an existing library of educational software, although readers may also find the design principles themselves to be useful. This project was funded by a seed grant from the Center for Innovative Learning Technologies funded by the National Science Foundation (REC # 9720384), and was partially supported by Educational Testing Service. Any opinions expressed in this publication are those of the authors and not necesarily of Educational Testing Service.     

Preliminary Evolutionary Explanations: A Basic Framework for Conceptual Change and Explanatory Coherence in Evolution

This study aimed to explore secondary students’ explanations of evolutionary processes, and to determine how consistent these were, after a specific evolution instruction. In a previous study it was found that before instruction students provided different explanations for similar processes to tasks with different content. Hence, it seemed that the structure and the content of the task may have had an effect on students’ explanations. The tasks given to students demanded evolutionary explanations, in particular explanations for the origin of homologies and adaptations. Based on the conclusions from the previous study, we developed a teaching sequence in order to overcome students’ preconceptions, as well as to achieve conceptual change and explanatory coherence. Students were taught about fundamental biological concepts and the several levels of biological organization, as well as about the mechanisms of heredity and of the origin of genetic variation. Then, all these concepts were used to teach about evolution, by relating micro-concepts (e.g. genotypes) to macro-concepts (e.g. phenotypes). Moreover, during instruction students were brought to a conceptual conflict situation, where their intuitive explanations were challenged as emphasis was put on two concepts entirely opposed to their preconceptions: chance and unpredictability. From the explanations that students provided in the post-test it is concluded that conceptual change and explanatory coherence in evolution can be achieved to a certain degree by lower secondary school students through the suggested teaching sequence and the explanatory framework, which may form a basis for teaching further about evolution.     

Exploring student ideas about biological variation

ABSTRACT

An understanding of biological variation is important for understanding ecological interactions, ecosystem function, and species’ response to environmental change. Biological variation is essential to species survival because natural selection acts upon the phenotypic variation within a population: the more varied the population’s genetic resources, the more likely that the population will persist into the future. We explored how students think about biological variation by evaluating written assessments and interviews of grades 6–16 students about starting a captive breeding programme for species conservation. We created a qualitative framework that describes levels of proficiency in student ideas about biological variation. Lower level responses reason about attributes related to an individual’s reproduction and survival rather than population-level variability. Student responses at a middle level of sophistication point to the importance of variation but do not link it mechanistically to species survival and resilience. We also describe alternative conceptions related to biological variation and natural selection which exist at all grade levels. Educators can use these findings to inform curriculum and instruction in terms of addressing important concept areas (e.g. variation at the population scale) and some common alternative conceptions that may impact an accurate understanding of natural selection and evolution.     

Learning about evolution and rejecting a belief in special creation: Effects of reflective reasoning skill,prior knowledge,prior belief and religious commitment

Students in three sections of a high school biology course were taught a unit on evolution and natural selection. Prior to instruction, students were pretested to determine their (a) reflective reasoning skill, (b) strength of religious commitment, (c) prior declarative knowledge of evolution and natural selection, and (d) beliefs in evolution or special creation and related religiously oriented beliefs. Following instruction the measures of declarative knowledge and beliefs were readministered. The study was designed to test (a) the hypothesis that the acquisition of domain-specific concepts and the modification of nonscientific beliefs largely depends upon reflective reasoning skill, not prior declarative knowledge; and (b) the hypothesis that strength of religious commitment and a belief in special creation hinder the acquisition of scientific beliefs. Although instruction produced no overall shift toward a belief in evolution, as predicted, reflective reasoning skill was significantly related to initial scientific beliefs, and reflective reasoning skill, but not prior declarative knowledge, was significantly related to gains in declarative knowledge. Reflective reasoning skill, however, was not significantly related to changes in beliefs. Also as predicted, strength of religious commitment was negatively correlated with initial belief in evolution and with a change in belief toward evolution. Interrelationships among the study's major variables, as well as educational implications, are discussed.     

What is the effect of talking heads in educational videos with different types of narrated slides?

Video-based learning plays an increasingly important role and thus the optimal design of video-based learning materials attracts the attention of scientists and practitioners alike. In this context, producers of educational videos often include a talking head in their videos, although theory (e.g., cognitive theory of multimedia learning) also suggests potential disadvantages for this format. Since talking heads attract a lot of visual attention, further empirical research is necessary to investigate whether a talking head can hinder learning, especially presented next to graphic-based learning content. To address this research gap, we conducted two online experiments to investigate the effects of a talking head in educational videos with narrated slides (short slideshow lectures) on learning outcomes (i.e., factual knowledge acquisition) and participants’ subjective ratings of the learning material (e.g., perceived learning). In Experiment 1 (N = 96), we varied whether the instructor’s talking head was present or absent in the videos as a between-factor, and whether the visual content on the slides was graphic-based (pictures, diagrams, maps) or text-based (bullet points) as a within-factor (slide type). In Experiment 2 (N = 184), we additionally varied as a between-factor whether the contents appeared sequentially or statically all at once (presentation type). Our results showed that the talking head did not affect learning outcomes, regardless of slide type and presentation type of the videos suggesting that the inclusion of a talking head offers neither clear advantages nor disadvantages. Potential explanations for the findings and directions for future research are discussed.     

国家级线上一流课程教学视频制作规范探析

教学视频是线上课程的主要教学资源,也是实施翻转课堂、线上线下混合教学的关键要素。高质量的教学资源,是提升线上教学质量的前提。以31门国家级线上一流课程的116个教学视频作为样本,从技术指标、拍摄方法、视听要素和内容结构等方面总结视频制作规范。研究表明,合理使用新技术、新标准、新方法是制作高质量教学视频的保障;利用视听要素,提高教学内容的教学性和吸引力是制作高质量教学视频的关键;精心设计的教学环节是制作高质量教学视频的基础。     

“微”时代之微课发展意义与存在问题探析

在信息时代互联网迅速发展的今天,微课的产生和发展给教育教学资源的开发打开了一条新的出路.微课指的是“按照新课程标准及教学实践要求,以教学视频为主要载体,反映教师在课堂教学过程中针对某个知识点或教学环节而开展教与学活动的各种教学资源有机组合”.微课正是基于网络多媒体技术及信息处理技术将“课”微处理化,形成了一段能在5-10分钟之内生动展示并陈述、解决一个核心重点问题的教学音视频,对教师的专业发展、学生的学习以及教育自身都具有长远的作用和意义.     

Promotion of autonomy for participation in physical activity: a study based on the trans-contextual model of motivation

The aim of this study was to analyse the effects of a school-based intervention to promote physical activity, utilising the postulates of the trans-contextual model of motivation. The study examined two separate classes of elementary school students (mean age 11.28?years), one of which served as the control group (n?=?26) and the other as the experimental group (n?=?21). The intervention in the experimental group consisted of showing videos related to physical activity participation, conducting discussions and doing tasks related to the content presented in the videos and conducting family discussions. Autonomy support from teachers, peers and parents; motivation in physical education and leisure time physical activity; the different variables of theory of planned behaviour; and physical activity, were measured before and after the intervention. Results showed an increase in teacher autonomy support, identified regulation in physical education, autonomy support from parents and peers, integrated and identified regulation in leisure time physical activity, control, subjective norm, intention and physical activity in the experimental group. Furthermore, this increase resulted in post-intervention differences across groups in such variables. Results are discussed in relation to the important role of families in the promotion of physical activity participation.     

Using Multiple Lenses to Examine the Development of Beginning Biology Teachers’ Pedagogical Content Knowledge for Teaching Natural Selection Simulations

Pedagogical content knowledge (PCK) has become a useful construct to examine science teacher learning. Yet, researchers conceptualize PCK development in different ways. The purpose of this longitudinal study was to use three analytic lenses to understand the development of three beginning biology teachers’ PCK for teaching natural selection simulations. We observed three early-career biology teachers as they taught natural selection in their respective school contexts over two consecutive years. Data consisted of six interviews with each participant. Using the PCK model developed by Magnusson et al. (1999), we examined topic-specific PCK development utilizing three different lenses: (1) expansion of knowledge within an individual knowledge base, (2) integration of knowledge across knowledge bases, and (3) knowledge that explicitly addressed core concepts of natural selection. We found commonalities across the participants, yet each lens was also useful to understand the influence of different factors (e.g., orientation, subject matter preparation, and the idiosyncratic nature of teacher knowledge) on PCK development. This multi-angle approach provides implications for considering the quality of beginning science teachers’ knowledge and future research on PCK development. We conclude with an argument that explicitly communicating lenses used to understand PCK development will help the research community compare analytic approaches and better understand the nature of science teacher learning.     

Indexed Captioned Searchable Videos: A Learning Companion for STEM Coursework

Videos of classroom lectures have proven to be a popular and versatile learning resource. A key shortcoming of the lecture video format is accessing the content of interest hidden in a video. This work meets this challenge with an advanced video framework featuring topical indexing, search, and captioning (ICS videos). Standard optical character recognition (OCR) technology was enhanced with image transformations for extraction of text from video frames to support indexing and search. The images and text on video frames is analyzed to divide lecture videos into topical segments. The ICS video player integrates indexing, search, and captioning in video playback providing instant access to the content of interest. This video framework has been used by more than 70 courses in a variety of STEM disciplines and assessed by more than 4000 students. Results presented from the surveys demonstrate the value of the videos as a learning resource and the role played by videos in a students learning process. Survey results also establish the value of indexing and search features in a video platform for education. This paper reports on the development and evaluation of ICS videos framework and over 5 years of usage experience in several STEM courses.     

论视频技术在高职思想政治理论课中的应用

随着信息技术的不断发展,视频技术作为一种新的教学手段在高职思想政治理论课中得到了广泛应用。视频技术引入高职思想政治理论课符合高职生的认知规律,有利于主动占领高职生思想政治教育阵地,有利于提高高职生的学习效果。但由于部分教师对视频的播放时机、内容选择和长度把握不够恰当,没能充分发挥视频的教育引导功能。要实现视频技术在高职思想政治理论课中的有效应用,需要明确视频运用的基本原则,选用恰当的视频内容,确定合理的运用时机,选择恰当的播放时间和合理的视频播放形式,加强师生的交流互动等。