Differences in how biology teachers represent content structure in classroom discourse: a video-based analysis

Despite the importance of pedagogical content knowledge (PCK) in practical teaching and the inconsistency of teacher quality in different regions in China, there is little empirical evidence for specific differences in teachers’ PCK in different districts in China. This study attempted to address this gap through analysis of practical teaching demonstrations by three pairs of biology teachers; each pair comprised one teacher from Beijing and one from Hebei province. The teaching content was the same for each pair, including a discussion of blood, blood type, and the heart. The practical teaching demonstration was videotaped for each teacher. Analysis of the PCK focused on one aspect: content structure. Analysis of the six lessons suggested that the Beijing biology teacher presented more structured biology terms than did the Handan biology teacher in each pair. The Beijing biology teachers also performed better in connecting the new knowledge with previously learned knowledge than Handan biology teachers. The current study contributes to the methods for capturing teachers’ PCK in classroom discourse, and it indicates specific differences between Handan and Beijing teachers in the ability to make connections in students’ knowledge.     

Biology student teachers’ dialogic talk in inquiry-based instruction

ABSTRACT

Inquiry-based learning has generally accepted by scholars as a most effective teaching approach in biology education. The talk during inquiry-based teaching needs to be practiced. There is less evidence how student teachers talk with students during their inquiry-based biology instruction. This knowledge is needed in supporting student teachers to develop their teachership in biology education. In this qualitative case study, the dialogic talk of biology student teachers (N = 6) was studied in the context of inquiry-based lessons in lower secondary school. The student teachers’ lessons were video and audio recorded and the data was analyzed using content analysis. The student teachers used dialogic talk in their inquiry-based instruction only occasionally, mainly in the examination and the conclusion stages. During the introduction stage, dialogic talk was less used and it was mainly explaining and instructing the content. In the examination stage, student teachers also guided students and stated facts. During the conclusion stage, student teachers mainly explained and also evaluated students’ statements. The lesson’s topics and methods used in inquiry-based learning may enable the dialogic talk of student teacher to some extent. However, teacher education should focus more on scaffolding student teachers’ talk with their students in all kinds of inquiry approaches.     

How to Identify and Interpret Evolutionary Tree Diagrams

Evolutionary trees are key tools for modern biology and are commonly portrayed in textbooks to promote learning about biological evolution. However, many people have difficulty in understanding what evolutionary trees are meant to portray. In fact, some ideas that current professional biologists depict with evolutionary trees are neither clearly defined nor conveyed to students. To help biology teachers and students learn how to more deeply interpret, understand and gain knowledge from diagrams that represent ancestor–descendant relationships and evolutionary lineages, we describe the different rooted and unrooted evolutionary tree visualisations and explain how they are best read. Examples from a study of tree-shaped diagrams in the journal Science are used to illustrate how to distinguish evolutionary trees from other tree-shaped representations that are easily misunderstood as visualising evolutionary relationships. We end by making recommendations for how our findings may be implemented in teaching practice in this important area of biology education.     

Make biology relevant again! Pre-service teachers’ views on the relevance of biology education

ABSTRACT

Biology education should be relevant to young students so that they can become interested in biology and understand biological topics in their everyday and vocational lives. We conducted interviews and collected mind maps to examine Finnish pre-service biology teachers’ (N = 16) views on the relevance of biology education. Furthermore, we analysed Finnish secondary school biology curricula, which were compared with the pre-service teachers’ answers. We classified the views on relevance into nine main categories using grounded theory as the methodological frame of reference. Pre-service teachers emphasised the relevance of biology to the student’s own life, whereas scientific practices and the nature of science were expressed in secondary school curricula more often. Novice pre-service teachers put more value on general knowledge, while more experienced pre-service teachers were more likely to mention sustainable futures and societal aspects in their reasoning. Based on the results, we identified two stages in the development of the views. This study suggests that pedagogical studies, teaching experience and teacher training have an impact on the pre-service teachers’ views about the relevance of biology education. Moreover, we could find differences between curricula and pre-service teachers’ views, especially regarding scientific practices and the role of the nature of science in biology education.     

Engaging students in constructing scientific explanations in biology classrooms: a lesson-design model

Abstract

Constructing scientific explanations of natural phenomena is an important aim of science education. Explanation oriented science teaching approaches encourage learners to engage in sense-making discussions and construct the causal accounts of the phenomena under study. This article demonstrates a lesson-design model that guides biology teachers on how to integrate explanation oriented teaching in their everyday practice. The proposed model includes six phases: (1) presenting a hooking activity; (2) formulating a how-why type focus question; (3) constructing the initial causal story; (4) using authentic data, scientific facts, principles, and disciplinary core ideas to revise-refine the causal story; (5) discussing-rewriting the refined causal story; (6) applying the causal-mechanistic knowledge in a new context or problem scenario. An eleventh-grade lesson on the topic ‘protein biosynthesis in cells’ serves an example about how this model can be operationalized to design and implement explanation oriented biology lessons.     

Good student questions in inquiry learning

Acquisition of scientific reasoning is one of the big challenges in education. A popular educational strategy advocated for acquiring deep knowledge is inquiry-based learning, which is driven by emerging ‘good questions’. This study will address the question: ‘Which design features allow learners to refine questions while preserving student ownership of the inquiry process?’ This design-based research has been conducted over several years with advanced high-school biology classes. The results confirm the central role of question elaboration as an interactive process that leads from vague to complex and adequate. To make this happen, the inquiry process must extend over a long time, learners and teachers should share a knowledge improvement goal, and text produced by students should be structured by question–answer pairs addressing a single concept using authentic resources. Further features are discussion with peers, teacher feedback with respect to answer elaboration and conceptual differentiation, and finally, teacher guidance that should fade out in successive inquiry cycles to ensure student responsibility.     

Teaching Evolution with Historical Narratives

This paper focuses on evolution as a unifying theme in biology education. Our aim is to argue that the different topics taught in secondary school biology classes should be enriched with and linked together by means of accounts of the history of life. We named this approach a “natural history perspective” on biology education. An essential aspect of the natural history perspective is the claim that evolutionary history forms the context for the development of an understanding of evolutionary processes. While there are some indications that a natural history perspective can function as a context for understanding micro-evolutionary processes, more research is called for.

Bdelloid rotifers: ‘sleeping beauties’ and ‘evolutionary scandals’, but not only

Bdelloid rotifers are mostly known for two peculiarities, continuous parthenogenetic reproduction and dormancy in response to habitat desiccation, a phenomenon named anhydrobiosis. These uncommon traits earned them the names of ‘evolutionary scandals’ and ‘sleeping beauties’, respectively. Relevant aspects of bdelloid biology have recently been described that connect parthenogenesis to anhydrobiosis and that might account for their evolutionary survival in spite of the conservative reproduction. In the present study, I explore recent literature, in the attempt to disentangle the apparent incongruency between the apomictic reproduction and the presumed long-term evolutionary survival of bdelloid species. Recent results remarkably improved our knowledge of bdelloid population biology, genetics, and molecular biology. The most relevant findings concern (i) acquisition of foreign genes through horizontal transfer, (ii) presence of divergent sequences possibly corresponding to ancient gene duplications and (iii) capacity to escape parasites: events that appear to be connected with dormancy. I also address the results of recent studies on the relationships between bdelloids and other rotifers, including acanthocephalans, in an attempt to highlight similarities and differences that should be clarified to better understand phylogenetic relationship among the Rotifera sensu lato.

     

A model for the evolutionary dynamics of cross-feeding polymorphisms in microorganisms

 Understanding mechanisms of evolutionary diversification is central to evolutionary biology. Microbes constitute promising model systems for observing processes of diversification directly in the laboratory. One of the main existing paradigms for microbial diversification is the evolution of cross-feeding polymorphisms, in which a strain specializing on a primary resource coexists with a cross-feeding strain that specializes on a waste product resulting from consumption of the primary resource. Here I propose a theoretical model for the evolutionary dynamics through which cross-feeding polymorphisms can gradually emerge from a single ancestral strain. The model is based on the framework of adaptive dynamics, which has proved to be very useful for studying adaptive processes of divergence under sympatric conditions. In particular, the phenomenon of evolutionary branching serves as a general paradigm for diversification. I show that evolutionary branching naturally occurs in evolutionary models of cross-feeding if (1) there is a trade-off between uptake efficiencies on the primary and secondary resources, and (2) this trade-off has positive curvature. The model also suggests that the evolution of cross-feeding should be more likely in chemostat cultures than in serial batch cultures, which conforms with empirical observations. Overall, the model provides a theoretical metaphor for the evolution of cross-feeding polymorphisms. Received: February 19, 2002 / Accepted: May 8, 2002     

More on how and why: cause and effect in biology revisited

In 1961, Ernst Mayr published a highly influential article on the nature of causation in biology, in which he distinguished between proximate and ultimate causes. Mayr argued that proximate causes (e.g. physiological factors) and ultimate causes (e.g. natural selection) addressed distinct ‘how’ and ‘why’ questions and were not competing alternatives. That distinction retains explanatory value today. However, the adoption of Mayr’s heuristic led to the widespread belief that ontogenetic processes are irrelevant to evolutionary questions, a belief that has (1) hindered progress within evolutionary biology, (2) forged divisions between evolutionary biology and adjacent disciplines and (3) obstructed several contemporary debates in biology. Here we expand on our earlier (Laland et al. in Science 334:1512–1516, 2011) argument that Mayr’s dichotomous formulation has now run its useful course, and that evolutionary biology would be better served by a concept of reciprocal causation, in which causation is perceived to cycle through biological systems recursively. We further suggest that a newer evolutionary synthesis is unlikely to emerge without this change in thinking about causation.     

Teaching biology in the thirties

Ernest J. Holmes, one of the first teachers of ‘biology’ in secondary schools and co-author of a seminal biology textbook, writes a personal account of teaching at a time when ‘biology’ as a school subject was just beginning to become accepted.     

“建立血糖调节模型”的教学设计与组织策略

在高中生物教学中,血糖平衡的调节一直是重要的教学内容。以往的教学设计思路主要是依靠教师讲述,学生被动接受,因此学生在学习上缺乏主动性。且由于内容比较抽象,学生很难真正理解。教师如何依据现代教育理论,通过组织和引导学生模拟血糖的调节机制,建构和不断修正动态的物理模型,再建构抽象的血糖调节的图解式概念模型,从而使学生深入理解血糖调节的机制,更好地理解体内激素对生命活动进行的调节,不仅是突破教学难点有效途径,对学生建立科学思维方式也具有重要的意义。结合课堂教学实际,介绍“建立血糖调节模型”的教学设计和“概念模型”的教学组织策略两个方面研究成果。     

Procedural understanding in biology: the ‘thinking behind the doing’

Several developments in science education aim to improve pupils' ability to ‘think scientifically’. This paper argues for the explicit teaching of the ideas that pupils need to ‘think about’ to do this; ideas related to the design of investigations and the collection, presentation, analysis, and evaluation of the resulting evidence — ideas which are important both for pupils who continue to study or work with biology and for all pupils to become biologically literate. This paper considers some of the concepts of evidence which are particularly important to biology, and discusses how and why the ideas could be taught.     

An untold story in biology: the historical continuity of evolutionary ideas of Muslim scholars from the 8th century to Darwin’s time

Textbooks on the history of biology and evolutionary thought do not mention the evolutionary ideas of Muslim scholars before Darwin’s time. This is part of a trend in the West to minimise the contributions of non-Western scientists to biology, human anatomy and evolutionary biology. Therefore, this paper focuses on the contributions of pre-Darwinian Muslim scholars to the history of evolutionary thought. Our review of texts from a wide range of historical times, and written in various languages, reveals that there were in fact several Muslim scholars who postulated evolutionary ideas, some with remarkable similarities to Darwin’s theory. These ideas included the adaptation and survival of the fittest, a specific origin of humans from apes/monkeys, the notion of evolutionary constraints, the occurrence of extinctions within taxa and hereditary variability. Moreover, while both the scientific community and the broader public generally base their knowledge on Western textbooks, several parts of the Muslim world have indicated an overall rejection of biological–including human–evolution. Therefore, to improve historical accuracy and create a better understanding of scientific history, the world’s diverse civilisations and their philosophies, this untold story should be widely disseminated to the scientific community and the general public.     

Origins of multicellular complexity: Volvox and the volvocine algae

The collection of evolutionary transformations known as the ‘major transitions’ or ‘transitions in individuality’ resulted in changes in the units of evolution and in the hierarchical structure of cellular life. Volvox and related algae have become an important model system for the major transition from unicellular to multicellular life, which touches on several fundamental questions in evolutionary biology. The Third International Volvox Conference was held at the University of Cambridge in August 2015 to discuss recent advances in the biology and evolution of this group of algae. Here, I highlight the benefits of integrating phylogenetic comparative methods and experimental evolution with detailed studies of developmental genetics in a model system with substantial genetic and genomic resources. I summarize recent research on Volvox and its relatives and comment on its implications for the genomic changes underlying major evolutionary transitions, evolution and development of complex traits, evolution of sex and sexes, evolution of cellular differentiation and the biophysics of motility. Finally, I outline challenges and suggest future directions for research into the biology and evolution of the volvocine algae.     

Pattern Cladistics and the ‘Realism–Antirealism Debate’ in the Philosophy of Biology

Despite the amount of work that has been produced on the subject over the years, the ‘transformation of cladistics’ is still a misunderstood episode in the history of comparative biology. Here, I analyze two outstanding, highly contrasting historiographic accounts on the matter, under the perspective of an influential dichotomy in the philosophy of science: the opposition between Scientific Realism and Empiricism. Placing special emphasis on the notion of ‘causal grounding’ of morphological characters (sensu Olivier Rieppel) in modern developmental biology’s (mechanistic) theories, I arrive at the conclusion that a ‘new transformation of cladistics’ is philosophically plausible. This ‘reformed’ understanding of ‘pattern cladistics’ entails retaining the interpretation of cladograms as ‘schemes of synapomorphies’, but in association to construing cladogram nodes as ‘developmental-genetic taxic homologies’, instead of ‘standard Darwinian ancestors’. The reinterpretation of pattern cladistics presented here additionally proposes to take Bas Van Fraassen’s ‘constructive empiricism’ as a philosophical stance that could properly support such analysis of developmental-genetic data for systematic purposes. The latter suggestion is justified through a reappraisal of previous ideas developed by prominent pattern cladists (mainly, Colin Patterson), which concerned a scientifically efficient ‘observable/non-observable distinction’ linked to the conceptual pair ‘ontogeny and phylogeny’. Finally, I argue that a robust articulation of Antirealist alternatives in systematics may provide a rational basis for its disciplinary separation from evolutionary biology, as well as for a critical reconsideration of the proper role of certain Scientific Realist positions, currently popular in comparative biology.     

Evolution and nature of science instruction

In this article, I provide an analysis of my work (1985–present) with non-major biology students and science teacher candidates in developing strategies for teaching and enhancing learning with respect to evolutionary science. This first-person account describes changes in evolution instruction over the course of a career based on personal experiences, research-informed practices, and a critical collaboration with colleague Mike U. Smith. I assert four insights concerning the influence and efficacy of teaching nature of science (NOS) prior to the introduction of evolution within college courses for science non-majors and science teacher candidates. These insights are: (a) teach explicit NOS principles first; (b) integrate evolution as a theme throughout a course in introductory biology (but after NOS principles have been introduced); (c) use active learning pedagogies; and (d) use non-threatening alternative assessments to enhance student learning and acceptance of evolutionary science. Together, these insights establish a pedagogy that I (and my colleagues) have found to be efficacious for supporting novice students as they engage in the study of evolutionary science.     

Evolutionary morphology and Evo-devo: Hierarchy and novelty

Although the role of morphology in evolutionary theory remains a subject of debate, assessing the contributions of morphological investigation to evolutionary developmental biology (Evo-devo) is a more circumscribed issue of direct relevance to ongoing research. Historical studies of morphologically oriented researchers and the formation of the Modern Synthesis in the Anglo-American context identify a recurring theme: the synthetic theory of evolution did not capture multiple levels of biological organization. When this feature is incorporated into a philosophical framework for explaining the origin of evolutionary innovations and novelties (a core domain of inquiry in Evo-devo) two specific roles for morphology can be described: (1) the conceptualization and operational identification of the targets of explanation; and (2) the elucidation of causal interactions at higher levels of organization during ontogeny and through evolutionary time. These roles are critical components of any adequate explanation of innovation and novelty though not exhaustive of the parts played by morphology in evolutionary investigation. They also invite reflection on what counts as an evolutionary cause in contemporary evolutionary biology.     

Misconceptions About Evolution in Brazilian Freshmen Students

Regarding such an important issue as our origin, as well as the origin of all biological diversity, it is surprising to realize that evolution still faces drawbacks in keeping its deserved notability as a unifying theory in biology. This does not happen because evolutionism lacks validity as a scientific theory, but rather because of several misconceptions regarding evolutionary biology that were and continue to be found in elementary and secondary education. Furthermore, mistaken evolutionary ideas also affect some philosophical and social issues. The aim of the present study was to evaluate knowledge about evolution among freshman students from distinct majoring areas at Universidade Estadual do Centro-Oeste do Paraná (UNICENTRO), Brazil. The research was carried out based on a ten-question questionnaire about evolution with distinct levels of difficulty, comprising the most observed misconceptions. In this study, 231 students attending classes in biological sciences (morning and evening schedule), exact sciences (agronomy, physics, chemistry, and math), and human sciences (history, geography, and pedagogy) were interviewed. The total average of right answers was 48.8%, and the highest average per course obtained was 58.7% from the students attending biological sciences (evening schedule). Although evolutionary biology and ecology are supposed to represent teaching guide issues according to the recommendations of the National Curricular Parameters for the Secondary School, the data obtained suggest that the evidence for evolution, the role of natural selection and random events, as well as the sources of variation, must be better focused at schools.     

The species flocks of lacustrine gastropods: <Emphasis Type="Italic">Tylomelania</Emphasis> on Sulawesi as models in speciation and adaptive radiation

Endemic radiations provide splendid opportunities for studies in evolutionary biology. Species flocks in ancient lakes, such as in Tanganyika, Malawi or Baikal, have featured prominently in evolutionary biology, viewing these “evolutionary theatres” as hotspots of diversification. However, following a century of neglect, the endemic evolution of limnic cerithioidean gastropods in the two central lake systems on the Indonesian island of Sulawesi (i.e. Lake Poso and the lakes of the Malili system, e.g. Danau Matano, Mahalona and Towuti) also provide instructive model cases for the study of speciation mechanisms, adaptive radiation and annidation (i.e. niche exploitation). We here discuss the evolutionary and taxonomic implications of the lacustrine species flocks in Tylomelania from these lakes in Sulawesi as an exceptional endemic assemblage of morphologically distinct viviparous pachychilid gastropods. This first comprehensive compilation of data on both ancient lake systems, Poso and Malili, offers a new perspective on ecological differentiation in this radiation. Presented here within the framework of the theory of evolutionary ecology it provides a research program for acquiring a synthetical perspective that includes morphology, molecular genetics, ecology and biogeography. In this context, it will be possible to compare the species flocks of these truly “Darwinian snails” on Sulawesi with the long enigmatic, so-called thalassoid (i.e. marine-like) gastropod radiation in East African’s Lake Tanganyika.