Students’ model-based explanations about natural selection and antibiotic resistance through socio-scientific issues-based learning

ABSTRACT

Antibiotic resistance (ABR) is a significant contemporary socio-scientific issue. To engage in informed reasoning about ABR, students need to understand natural selection. A secondary science unit was designed and implemented, combining an issues-based approach and model-based reasoning, to teach students about natural selection and ABR. This sequential explanatory mixed methods study explored students’ explanations of natural selection. Students created model-based explanations (MBEs) about ABR and verbally explained generalised natural selection during semi-structured interviews. Students’ MBEs significantly increased in natural selection content, and misconceptions about natural selection and ABR significantly decreased after the unit. However, students’ explanations of generalised natural selection differed from ABR explanations. Students struggled to include mutation as the cause of initial variation when explaining generalised natural selection, whereas students included mutation when explaining ABR but often did so after selection pressure. Qualitative analysis indicated students correctly explained ABR or correctly explained generalised natural selection, but none correctly explained both. Students who did understand ABR struggled to apply their understanding to a context other than ABR. This study demonstrates contextual differences in students’ natural selection ideas and provides implications for natural selection instruction. While ABR is a compelling issue to contextualise natural selection instruction, it may be problematic.

KEYWORDS:

• Natural selection
• secondary students
• model-based reasoning
• socio-scientific issue
• modelling
• antibiotic resistance

Acknowledgements

The ideas expressed in this material are those of the authors and do not necessarily reflect the views of the NSF. We appreciate the interest and participation of the teacher and students who made this work possible.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Amanda Peel http://orcid.org/0000-0002-2704-3911

Laura Zangori http://orcid.org/0000-0002-7512-5559

Patricia Friedrichsen http://orcid.org/0000-0001-8777-2107

Troy Sadler http://orcid.org/0000-0002-9401-0300

Additional information

Funding

This research was supported by the National Science Foundation [grants number IIA-1355406], [grants number 1140462].