The DNA Landscape: Development and Application of a New Framework for Visual Communication about DNA

Abstract

Learning molecular biology involves using visual representations to communicate ideas about largely unobservable biological processes and molecules. Genes and gene expression cannot be directly visualized, but students are expected to learn and understand these and related concepts. Theoretically, textbook illustrations should help learners master such concepts, but how are genes and other DNA-linked concepts illustrated for learners? We examined all DNA-related images found in 12 undergraduate biology textbooks to better understand what biology students encounter when learning concepts related to DNA. Our analysis revealed a wide array of DNA images that were used to design a new visual framework, the DNA Landscape, which we applied to more than 2000 images from common introductory and advanced biology textbooks. All DNA illustrations could be placed on the landscape framework, but certain positions were more common than others. We mapped figures about "gene expression" and "meiosis" onto the landscape framework to explore how these challenging topics are illustrated for learners, aligning these outcomes with the research literature to showcase how the overuse of certain representations may hinder, instead of help, learning. The DNA Landscape is a tool to promote research on visual literacy and to guide new learning activities for molecular biology.

FIGURE 1.

Creation and revision of the DNA Landscape framework. A flowchart of the process is illustrated with blue ovals for stages of the framework development; green indicates data, and pink shows theories that informed the work.

FIGURE 2.

The DNA Landscape and Category Definitions. (A) Examples of DNA illustrations that would fall into each of the nine categories of the DNA Landscape with scale indicating the focus of the illustration, and level of abstraction indicating the relationship to the actual molecule. (B) Definitions for each of the nine categories of the DNA Landscape.

FIGURE 3.

The Landscape of DNA representations in textbooks. Analysis includes six introductory (569 figures) and six advanced (1477 figures) textbooks. Each square on the matrix is divided in half: figures from introductory books are on the left, and figures from advanced books are on the right. The percentage of figures that fell into each category for all introductory or all advanced textbooks is shown, with shading corresponding to frequency of usage (lightest for least common, darkest for most common, where every 10% increase is shaded a little darker).

FIGURE 4.

The Landscape of DNA representations about gene expression. Analysis includes six introductory (235 figures) and six advanced (555 figures) textbooks. Each square on the matrix is divided in half (introductory books, left; advanced books, right). The percentage of figures that fell into each category for all introductory or all advanced textbooks is shown, with shading corresponding to frequency of usage.

FIGURE 5.

The Landscape of DNA representations about meiosis. Analysis includes six introductory (91 figures) and six advanced (127 figures) textbooks. Each square on the matrix is divided in half (introductory books, left; advanced books, right). The percentage of figures that fell into each category for all introductory or all advanced textbooks is shown, with shading corresponding to frequency of usage.