The need for molecular genetic perspectives in evolutionary education (and vice versa)

Assessing how well students understand the molecular basis of evolution by natural selection

Researchers have called for undergraduate courses to update teaching frameworks based on the Modern Synthesis with insights from molecular biology, by stressing the molecular underpinnings of variation and adaptation. To support this goal, we developed a modified version of the widely used Assessing Conceptual Reasoning of Natural Selection (ACORNS) instrument. The expanded tool, called the E-ACORNS, is explicitly designed to test student understanding of the connections among genotypes, phenotypes, and fitness. E-ACORNS comprises a slight modification to the ACORNS open-response prompts and a new scoring rubric. The rubric is based on five core concepts in evolution by natural selection, with each concept broken into elements at the novice, intermediate, and expert-level understanding. Initial tests of the E-ACORNS showed that (1) upper-level undergraduates can score responses reliably and quickly, and (2) students who were just starting an introductory biology series for majors do not yet grasp the molecular basis of phenotypic variation and its connection to fitness.

A CURE on the Evolution of Antibiotic Resistance in Escherichia coli Improves Student Conceptual Understanding

We developed labs on the evolution of antibiotic resistance to assess the costs and benefits of replacing traditional laboratory exercises in an introductory biology course for majors with a course-based undergraduate research experience (CURE). To assess whether participating in the CURE imposed a cost in terms of exam performance, we implemented a quasi-experiment in which four lab sections in the same term of the same course did the CURE labs, while all other students did traditional labs. To assess whether participating in the CURE impacted other aspects of student learning, we implemented a second quasi-experiment in which all students either did traditional labs over a two-quarter sequence or did CURE labs over a two-quarter sequence. Data from the first experiment showed minimal impact on CURE students' exam scores, while data from the second experiment showed that CURE students demonstrated a better understanding of the culture of scientific research and a more expert-like understanding of evolution by natural selection. We did not find disproportionate costs or benefits for CURE students from groups that are minoritized in science, technology, engineering, and mathematics.

Antibiotic resistant pathogen outbreak investigation: an interdisciplinary module to teach fundamentals of evolutionary biology

The evolution of resistance to antibiotics provides a timely and relevant topic for teaching undergraduate students evolutionary biology. Here, we present a module incorporating modified sequencing data from eight antibiotic resistant pathogen outbreaks in hospital settings with bioinformatics and phylogenetic analyses. This module uses whole genome sequencing data from hospital outbreaks investigated by the Centers for Disease Control and Prevention to provide examples of antibiotic resistance spread. Students work in groups to analyze outbreak data to identify the bacterial species and antibiotic resistance genes, to infer a phylogenetic tree examining relatedness among isolates, and to determine a possible source of the outbreak. Students then compile their results in individual reports and provide recommendations for preventing the further spread of antibiotic resistant organisms. In addition to providing genomic outbreak data, we include a teaching concepts guide discussing three integral components of the module: how evolutionary biology concepts of natural selection and competition impact antibiotic resistance; outbreak investigation information to aid in phylogenetic analysis and creation of recommendations; and instructions for the bioinformatics protocol. Completion of this module provides students an opportunity to think critically about the evolution of resistance, practice bioinformatics techniques, and relate evolutionary biology to current events.

Teaching genetics prior to teaching evolution improves evolution understanding but not acceptance

What is the best way to teach evolution? As microevolution may be configured as a branch of genetics, it being a short conceptual leap from understanding the concepts of mutation and alleles (i.e., genetics) to allele frequency change (i.e., evolution), we hypothesised that learning genetics prior to evolution might improve student understanding of evolution. In the UK, genetics and evolution are typically taught to 14- to 16-y-old secondary school students as separate topics with few links, in no particular order and sometimes with a large time span between. Here, then, we report the results of a large trial into teaching order of evolution and genetics. We modified extant questionnaires to ascertain students’ understanding of evolution and genetics along with acceptance of evolution. Students were assessed prior to teaching, immediately post teaching and again after several months. Teachers were not instructed what to teach, just to teach in a given order. Regardless of order, teaching increased understanding and acceptance, with robust signs of longer-term retention. Importantly, teaching genetics before teaching evolution has a significant (p < 0.001) impact on improving evolution understanding by 7% in questionnaire scores beyond the increase seen for those taught in the inverse order. For lower ability students, an improvement in evolution understanding was seen only if genetics was taught first. Teaching genetics first additionally had positive effects on genetics understanding, by increasing knowledge. These results suggest a simple, minimally disruptive, zero-cost intervention to improve evolution understanding: teach genetics first. This same alteration does not, however, result in a significantly increased acceptance of evolution, which reflects a weak correlation between knowledge and acceptance of evolution. Qualitative focus group data highlights the role of authority figures in determination of acceptance.

What is the best way to teach evolution? We hypothesised that if students know the fundamental concepts of genetics, then this might help them understand evolution better. To evaluate this, we performed a large trial in which pupils in United Kingdom secondary schools were either taught genetics and then evolution or evolution and then genetics. We found that the students being taught genetics first had a 5%–10% improvement in their understanding of evolution, above that shown in the group taught evolution first. The change was seen in both higher- and foundation-ability classes. Indeed, in the foundation classes the genetics-first approach was the only approach that enabled an increase in evolution understanding. Teaching genetics first comes at no cost to genetics understanding (and may even improve it). However, the genetics-first approach was no different from the evolution-first approach in helping the acceptance of evolution. Qualitative follow-up studies indicated a major role for authority figures in determining acceptance, potentially explaining the weak correlation between understanding and acceptance. These results suggest a simple, minimally disruptive, zero-cost intervention to improve evolution understanding: teach genetics first.

DNA Re-EvolutioN: a game for learning molecular genetics and evolution

Evolution is a main concept in biology, but not many students understand how it works. In this article we introduce the game DNA Re-EvolutioN as an active learning tool that uses genetic concepts (DNA structure, transcription and translation, mutations, natural selection, etc.) as playing rules. Students will learn about molecular evolution while playing a game that mixes up theory and entertainment. The game can be easily adapted to different educational levels. The main goal of this play is to arrive at the end of the game with the longest protein. Students play with pawns and dices, a board containing hypothetical events (mutations, selection) that happen to molecules, "Evolution cards" with indications for DNA mutations, prototypes of a DNA and a mRNA chain with colored "nucleotides" (plasticine balls), and small pieces simulating t-RNA with aminoacids that will serve to construct a "protein" based on the DNA chain. Students will understand how changes in DNA affect the final protein product and may be subjected to positive or negative selection, using a didactic tool funnier than classical theory lectures and easier than molecular laboratory experiments: a flexible and feasible game to learn and enjoy molecular evolution at no-cost. The game was tested by majors and non-majors in genetics from 13 different countries and evaluated with pre- and post-tests obtaining very positive results.

Are Africans, Europeans, and Asians different "races"? A guided-inquiry lab for introducing undergraduate students to genetic diversity and preparing them to study natural selection

Many students do not recognize that individual organisms within populations vary, and this may make it difficult for them to recognize the essential role variation plays in natural selection. Also, many students have weak scientific reasoning skills, and this makes it difficult for them to recognize misconceptions they might have. This paper describes a 2-h laboratory for college students that introduces them to genetic diversity and gives them practice using hypothetico-deductive reasoning. In brief, the lab presents students with DNA sequences from Africans, Europeans, and Asians, and asks students to determine whether people from each continent qualify as distinct "races." Comparison of the DNA sequences shows that people on each continent are not more similar to one another than to people on other continents, and therefore do not qualify as distinct races. Ninety-four percent of our students reported that the laboratory was interesting, and 79% reported that it was a valuable learning experience. We developed and used a survey to measure the extent to which students recognized variation and its significance within populations and showed that the lab increased student awareness of variation. We also showed that the lab improved the ability of students to construct hypothetico-deductive arguments.