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Termites are social insects with high species diversity in tropical ecosystems. Multivariate analysis with near-infrared spectroscopy (NIRS) and data interpretation can separate social insects belonging to different colonies of the same species. The objective of this study was to propose the use of discriminant analysis by partial least squares (PLS-DA) combined with NIRS to identify the colonial origin of the Syntermes grandis (Rambur, 1842) (Blattodea: Termitidae) in 2 castes. Six ground S. grandis colonies were identified and mapped; 30 workers and 30 soldier termites in each colony were submitted to spectral measurement with NIRS. PLS-DA applied to the termites' spectral absorbance was used to detect a spectral pattern per S. grandis colony by caste. PLS-DA regression with NIRS proved to be an approach with 99.9% accuracy for identifying the colonial origin of S. grandis workers and 98.3% for soldiers. The methodology showed the importance of qualitatively characterizing the colonial phenotypic response of this species. NIRS is a high-precision approach to identifying the colony origin of S. grandis workers and soldiers. The PLS-DA can be used to design ecological field studies to identify colony territorial competition and foraging behavior of subterranean termite species. [ABSTRACT FROM AUTHOR]

As part of a teacher training project, 16 future chemistry teachers participated in a dramatisation activity (a mock trial of the Fritz Haber case), in which they discussed a controversy concerning an event from the history of science: the awarding of the Nobel Prize in Chemistry to Fritz Haber in 1918. Preparations for the role-play activity, the dramatisation of the mock trial, and the subsequent discussions were video-recorded. We also collected the written material produced by the pre-service teachers and the reflective journals they produced during their involvement with the activity. This article discusses the contributions of such an experience to future teachers' knowledge on aspects related to both nature of science and argumentation, as well as to their views on their future actions related to authentic teaching "of" and "about" science. The results show that such contributions were meaningful.

This paper discusses the use of non-verbal representations in a modelling-based science teaching context, in which argumentative and explanatory situations occur. More specifically, we analyse how the students and teacher use representations in their discourse in modelling activities, and we discuss the relationships between the functions of these representations and the demands of the explanatory and argumentative situations that exist in that classroom. The data were collected by video recording all the classes in which a teaching sequence about intermolecular interactions was used--a topic which the students had not previously studied. In the activities, the students had to create, express, test, and discuss models in order to understand the difference between intermolecular and interatomic interactions, as well as their influences on the properties of substances. Initially, we selected excerpts of the recorded classes in which a non-verbal representation was used. Then, we used criteria to identify the argumentative and explanatory situations (previously defined), and we created categories for the functions of the representations that were used in order to analyse all the identified situations. The analysis supports conclusions indicating the relevance of the use of non-verbal representations in the construction, use, and defence of explanations. As the defence of explanations was the main context in which argumentative situations occurred in this study, our conclusions also indicate the contribution that representations make towards changing the status of the students' explanations.

Previous research on argumentation in science education has focused on the understanding of relationships between modeling and argumentation (an important topic that only recently has been addressed in few empirical studies), and the methodological difficulties related to the analysis of arguments produced in classrooms. Our study is related to these two aspects. This paper introduces an instrument to analyze arguments produced by students involved in modeling-based lessons, and discusses the instrument in the light of the current literature. This instrument has been successfully used to analyze arguments in modeling-based contexts through focus on analysis of plausibility of arguments regarding a given idea or model, and a documentation of the main elements (justification, evidence) and goals of an argument (explanation and persuasion). It has some advantages over other proposals found in the literature, mainly the consideration of the notion of scientific curricular argument (that allows the analysis of arguments in the light of student's knowledge and evidence available in the modeling process), and the distinction between the types of justification (that are important for monitoring the understanding of abstract phenomena). Therefore, it supports the analysis of argumentative situations that occur in regular classes, showing how the quality of students' arguments varies when they participate in distinct activities.

Some studies related to the nature of scientific knowledge demonstrate that modelling is an inherently argumentative process. This study aims at discussing the relationship between modelling and argumentation by analysing data collected during the modelling-based teaching of ionic bonding and intermolecular interactions. The teaching activities were planned from the transposition of the main modelling stages that constitute the "Model of Modelling Diagram" so that students could experience each of such stages. All the lessons were video recorded and their transcriptions supported the elaboration of case studies for each group of students. From the analysis of the case studies, we identified argumentative situations when students performed all of the modelling stages. Our data show that the argumentative situations were related to sense making, articulating and persuasion purposes, and were closely related to the generation of explanations in the modelling processes. They also show that representations are important resources for argumentation. Our results are consistent with some of those already reported in the literature regarding the relationship between modelling and argumentation, but are also divergent when they show that argumentation is not only related to the model evaluation phase.

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