title: Crossing the Threshold: Bringing Biological Variation to the Foreground.
abstract: Threshold concepts have been referred to as "jewels in the curriculum": concepts that are key to competency in a discipline but not taught explicitly. In biology, researchers have proposed the idea of threshold concepts that include such topics as variation, randomness, uncertainty, and scale. In this essay, we explore how the notion of threshold concepts can be used alongside other frameworks meant to guide instructional and curricular decisions, and we examine the proposed threshold concept of variation and how it might influence students' understanding of core concepts in biology focused on genetics and evolution. Using dimensions of scientific inquiry, we outline a schema that may allow students to experience and apply the idea of variation in such a way that it transforms their future understanding and learning of genetics and evolution. We encourage others to consider the idea of threshold concepts alongside the Vision and Change core concepts to provide a lens for targeted instruction and as an integrative bridge between concepts and competencies.
authors.affiliation: Biology Core Curriculum (Biocore), University of Wisconsin-Madison, Madison, WI 53706 jcbatzli@wisc.edu.
authors.forename: Janet M
authors.initials: JM
authors.lastname: Batzli
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309.
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Knight
authors.affiliation: Department of Integrative Biology, University of Colorado Denver, Denver, CO 80217.
authors.forename: Laurel M
authors.initials: LM
authors.lastname: Hartley
authors.affiliation: Department of Biology, Point Loma Nazarene University, San Diego, CA 92106.
authors.forename: April Cordero
authors.initials: AC
authors.lastname: Maskiewicz
authors.affiliation: Department of Science, Southwest Minnesota State University, Marshall, MN 56258.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Desy
mesh_terms: D000872:Anthocyanins / Q000378:metabolism; D001695:Biology / Q000193:education*; D029741:Brassica rapa / Q000235:genetics; D003479:Curriculum; D040582:Inheritance Patterns / Q000235:genetics
chemical_list: D000872:Anthocyanins