Science education often fails to address the actual range of adolescents' interests. One such interest is music. Research shows that young people devote large amounts of time and money to music. By tapping into students' interest in music, affective outcomes can be achieved in the biology classroom. This article describes a project-based learning activity that studies the influence of music on seed germination. Part of the student project is to conduct a literature search on the influence of music on plants, and possibly also on people (its biological, psychological, and social effects). The project is contextualized in the indigenous practice of making music while planting crops. There is a growing body of literature suggesting that music can improve crop yields. Students are required to follow the key features of project-based learning to plan and execute an inquiry to determine the influence of music on seed germination. Students undertaking a literature study will find research showing that music affects the viscosity of the plasmalemma and the availability of intercellular Ca2+, which, in turn, influences the activity of membrane-based enzymes. This can lead to larger amounts of water, nutrients, and growth regulators entering the plant cell. The article also reflects on data obtained from high school biology students as they engage in the learning activity.

Introduction: Tapping into Students' Interest in Music to Achieve Affective Outcomes

Stotsky (2011) makes the statement that schools have long failed to address the real range of adolescents' interests. By considering the interests of adolescents, we could make learning in the biology classroom more meaningful to learners and address affective outcomes (such as students' interest and motivation) that are often marginalized. Miranda (2013) has shown that young people devote large amounts of time and money to listening to music. Music is an important aspect of the contemporary lives of media-socializing 21st-century adolescents (Brown & Bobkowski, 2011).

Research shows that music influences people on several levels – namely biological, psychological, and social (Miranda, 2013). It is, therefore, possible for students to write theoretically about the influence of music on people, but not possible to conduct research on this in the school laboratory because of ethical, among other, considerations. This project-based learning activity is, therefore, designed as a laboratory investigation in which plants are used. The focus on plants also serves a secondary goal. Çil (2015) makes a convincing argument that many children are not aware of plants in their environment. Wandersee and Schussler (1999) coined the term plant blindness, referring to the inability of human beings to notice the plants in their environment although they encounter them frequently. Çil (2015) is of the opinion that a major reason for this is the way in which teachers present botany to students, and she advocates for a more interdisciplinary, integrated, and thematic approach to plant studies. By focusing on the influence of music on seed germination, the interest of students in plants could be enhanced. A secondary affective outcome of this project-based learning activity could, therefore, be the development of an interest in botanical themes.

Work by De Beer (2012) and by De Beer and Petersen (2017a) has shown that indigenous knowledge holds affective affordances in the biology classroom, as it can promote students' interest in plant studies. Here, I provide an example of one such interdisciplinary approach in which students engage in project-based learning by investigating the influence of music on seed germination. The learning activity is contextualized in the indigenous practice of playing music while planting crops.

In this activity, the effect of various music genres on seed germination can be investigated – such as classical, rock, acid rock, pop, heavy metal, hip-hop, opera, rap, or ballads. Students should formulate hypotheses for their investigations, based on known indigenous knowledge and practices. Such an approach might help students view plants from a different perspective (Çil, 2015), without using anthropomorphic explanations. Most students will be curious to determine what effect their favorite music genre has on seed germination. In addition, as I realized while undertaking my own similar investigation, there are a large number of variables that students need to account for – such as season, light, heat, moisture, seed type, music genre, frequencies of the sound waves, volume, and time of exposure – which offers a powerful learning experience. This complexity was demonstrated in the student posters that provided data for this article.

The research reflected on here was inspired by a report of the World Intellectual Property Organization (2006) on agricultural practices in the Philippines and an article by Dimaporo and Fernandez (2007) on the same topic. For the Maranao people in the Philippines, rituals form part of agricultural practices. Planting activities (mainly for rice) are accompanied by music, chanting, and dances (World Intellectual Property Organization, 2006). Dimaporo and Fernandez (2007) claim that these ceremonies are not simply cultural or superstitious but relate to astronomy, quantum mechanics, and metaphysics. This led me to a comprehensive body of scientific literature on the influence of music on seed germination. The literature includes reports that music improves yields in tomatoes, barley, vegetables, and other crops (Chowdhury et al., 2014). Table 1 provides an overview of the literature that students can consult.

Table 1.
Literature that students can consult in their investigations.
TopicReferences to Consult
Experiments on the influence of music on seed germination Collins, M.E. & Foreman, J.E.K. (2001). The effect of sound on the growth of plants. Canadian Acoustics, 29(2), 3–8.
Ekici, N., Dane, F., Mamedova, L., Metin, I. & Huseyinov, M. (2007). The effects of different musical instruments on root growth and mitosis in onion (Allium cepa) root apical meristem. Asian Journal of Plant Sciences, 6, 369–373.
Meng, Q., Zhou, Q., Zheng, S. & Gao, Y. (2012). Responses on photosynthesis and variable chlorophyll fluorescence of Fragaria ananassa under sound wave. Energy Procedia, 16, 346–352.
Teixeira da Silva, J.A. & Dobránszki, J. (2014). Sonication and ultrasound: impact on plant growth and development. Plant Cell, Tissue, and Organ Culture, 117, 131–143. 
Influence of different genres of music on seed germination Chivukula, V. & Ramaswamy, S. (2014). Effect of different types of music on Rosa chenensis plants. International Journal of Environmental Science and Development, 5, 431–434.
Retallack, D. & Broman, F. (1973). Response of growing plants to the manipulation of their environment. In The Sound of Music and Plants. Santa Monica, CA: DeVorss.
Sulong, N.A., Khalil, N.I.M., Dahari, M.I. & Zakaria, A.A. (2016). Effect of different sound genres on in vitro seed germination of Grammatophyllum hybrid and Grammatophyllum stapeliiflorum orchids. Open Conference Proceedings Journal, 7, 94–103.
Vanol, D. & Vaidya, R. (2014). Effect of sound (music and noise) and varying frequency on growth of guar or cluster bean seed germination and growth of plants. Quest, 2(3), 9–14. 
The mechanism of action on seeds (physiology) Ananthakrishnan, G., Xia, X., Amutha, S., Singer, S., Muraganantham, M., Yablomsky, S., et al. (2007). Ultrasonic treatment stimulates multiple shoot regeneration and explant enlargement in recalcitrant squash cotyledon explants in vitro. Plant Cell Reports, 26, 267–276.
Chowdhury, A.R. & Gupta, A. (2015). Effect of music on plants – an overview. International Journal of Integrative Sciences, Innovation and Technology, 4(6), 30–34.
Ekici, N., Dane, F., Mamedova, L., Metin, I. & Huseyinov, M. (2007). The effects of different musical instruments on root growth and mitosis in onion (Allium cepa) root apical meristem. Asian Journal of Plant Sciences, 6, 369–373.
Gagliano, M., Renton, M., Depczynski, M. & Mancuso, S. (2014). Experience teaches plants to learn faster and forget slower in environments where it matters. Oecologia, 175, 63–72.
Teixeira da Silva, J.A. & Dobránszki, J. (2014). Sonication and ultrasound: impact on plant growth and development. Plant Cell, Tissue, and Organ Culture, 117, 131–143.
Wang, B., Zhao, H., Liu, Y. & Sakanishi, A. (2001). The effects of alternative stress on the cell membrane deformability of chrysanthemum callus cells. Colloids and Surfaces B, 20, 321–325.
Wang, B., Zhao, H., Wang, X., Duan, C., Wang, D. & Sakanishi, A. (2002). Influence of sound stimulation on plasma membrane H+-ATPase activity. Colloids and Surfaces B, 25, 183–188.
Wang, X., Wang, B., Jia, Y., Duan, C. & Sakanishi, A. (2003). Effect of sound wave on the synthesis of nucleic acid and protein in chrysanthemum. Colloids and Surfaces B, 29, 99–102. 
Influence of music on humans Huron, D. (2003). Is music an evolutionary adaptation? In I. Peretz & R. Zatorre (Eds.), The Cognitive Neuroscience of Music (pp. 57–75). New York, NY: Oxford University Press.
Juslin, P.N., Liljestrom, S., Vastfjall, D., Barradas, G. & Silva, A. (2008). An experience sampling study of emotional reactions to music: listener, music and situation. Emotion, 8, 668–683.
Khalfa, S., Bella, S.D., Roy, M., Peretz, I. & Lupien, S.J. (2003). Effects of relaxing music on salivary cortisol level after psychological stress. Annals of the New York Academy of Sciences, 999, 374–376.
Menon, V. & Levitin, D.J. (2005). The rewards of music listening: response and physiological connectivity of the mesolimbic system. NeuroImage, 28, 175–184.
Peretz, I. & Zatorre, R. (2003). The Cognitive Neuroscience of Music. New York, NY: Oxford University Press. 
TopicReferences to Consult
Experiments on the influence of music on seed germination Collins, M.E. & Foreman, J.E.K. (2001). The effect of sound on the growth of plants. Canadian Acoustics, 29(2), 3–8.
Ekici, N., Dane, F., Mamedova, L., Metin, I. & Huseyinov, M. (2007). The effects of different musical instruments on root growth and mitosis in onion (Allium cepa) root apical meristem. Asian Journal of Plant Sciences, 6, 369–373.
Meng, Q., Zhou, Q., Zheng, S. & Gao, Y. (2012). Responses on photosynthesis and variable chlorophyll fluorescence of Fragaria ananassa under sound wave. Energy Procedia, 16, 346–352.
Teixeira da Silva, J.A. & Dobránszki, J. (2014). Sonication and ultrasound: impact on plant growth and development. Plant Cell, Tissue, and Organ Culture, 117, 131–143. 
Influence of different genres of music on seed germination Chivukula, V. & Ramaswamy, S. (2014). Effect of different types of music on Rosa chenensis plants. International Journal of Environmental Science and Development, 5, 431–434.
Retallack, D. & Broman, F. (1973). Response of growing plants to the manipulation of their environment. In The Sound of Music and Plants. Santa Monica, CA: DeVorss.
Sulong, N.A., Khalil, N.I.M., Dahari, M.I. & Zakaria, A.A. (2016). Effect of different sound genres on in vitro seed germination of Grammatophyllum hybrid and Grammatophyllum stapeliiflorum orchids. Open Conference Proceedings Journal, 7, 94–103.
Vanol, D. & Vaidya, R. (2014). Effect of sound (music and noise) and varying frequency on growth of guar or cluster bean seed germination and growth of plants. Quest, 2(3), 9–14. 
The mechanism of action on seeds (physiology) Ananthakrishnan, G., Xia, X., Amutha, S., Singer, S., Muraganantham, M., Yablomsky, S., et al. (2007). Ultrasonic treatment stimulates multiple shoot regeneration and explant enlargement in recalcitrant squash cotyledon explants in vitro. Plant Cell Reports, 26, 267–276.
Chowdhury, A.R. & Gupta, A. (2015). Effect of music on plants – an overview. International Journal of Integrative Sciences, Innovation and Technology, 4(6), 30–34.
Ekici, N., Dane, F., Mamedova, L., Metin, I. & Huseyinov, M. (2007). The effects of different musical instruments on root growth and mitosis in onion (Allium cepa) root apical meristem. Asian Journal of Plant Sciences, 6, 369–373.
Gagliano, M., Renton, M., Depczynski, M. & Mancuso, S. (2014). Experience teaches plants to learn faster and forget slower in environments where it matters. Oecologia, 175, 63–72.
Teixeira da Silva, J.A. & Dobránszki, J. (2014). Sonication and ultrasound: impact on plant growth and development. Plant Cell, Tissue, and Organ Culture, 117, 131–143.
Wang, B., Zhao, H., Liu, Y. & Sakanishi, A. (2001). The effects of alternative stress on the cell membrane deformability of chrysanthemum callus cells. Colloids and Surfaces B, 20, 321–325.
Wang, B., Zhao, H., Wang, X., Duan, C., Wang, D. & Sakanishi, A. (2002). Influence of sound stimulation on plasma membrane H+-ATPase activity. Colloids and Surfaces B, 25, 183–188.
Wang, X., Wang, B., Jia, Y., Duan, C. & Sakanishi, A. (2003). Effect of sound wave on the synthesis of nucleic acid and protein in chrysanthemum. Colloids and Surfaces B, 29, 99–102. 
Influence of music on humans Huron, D. (2003). Is music an evolutionary adaptation? In I. Peretz & R. Zatorre (Eds.), The Cognitive Neuroscience of Music (pp. 57–75). New York, NY: Oxford University Press.
Juslin, P.N., Liljestrom, S., Vastfjall, D., Barradas, G. & Silva, A. (2008). An experience sampling study of emotional reactions to music: listener, music and situation. Emotion, 8, 668–683.
Khalfa, S., Bella, S.D., Roy, M., Peretz, I. & Lupien, S.J. (2003). Effects of relaxing music on salivary cortisol level after psychological stress. Annals of the New York Academy of Sciences, 999, 374–376.
Menon, V. & Levitin, D.J. (2005). The rewards of music listening: response and physiological connectivity of the mesolimbic system. NeuroImage, 28, 175–184.
Peretz, I. & Zatorre, R. (2003). The Cognitive Neuroscience of Music. New York, NY: Oxford University Press. 

Engaging with Literature on the Influence of Music on Seed Germination (and, Optionally, on People)

While engaging in this project, students could (depending on how you phrase the assignment) engage with two areas of literature by (1) reviewing research reports on the influence of music on seed germination and/or (2) investigating studies on the influence of music on people (refer to Table 1).

Since the 1960s, experiments have been done on the influence of music on plant growth. It is of evolutionary importance that plants can sense and respond to environmental stimuli such as light, temperature, gravity, and touch (Telewski, 2006). The perception of sound by plants would, therefore, also hold evolutionary benefit. It has been shown that sound, as an external factor, has a big influence on the biological index of plants (Bochu et al., 1998; Zhao et al., 2000; Chowdhury et al., 2014), and studies have reported enhanced seed germination in various seeds when exposed to music. Additionally, Retallack and Broman (1973), Vanol and Vaidya (2014), and others have shown that, during controlled experiments, plants respond differently to different types of music. Although the influence of sound waves on plant tissues is still not well understood, several research studies provide compelling evidence that sound waves influence plant cell morphology, biochemistry, and gene expression. It is important that students engage in the tentativeness of science as a tenet. Thus, it is vital that they engage with literature and realize that, as the body of research evidence grows, plant physiologists are developing a more nuanced understanding of the mechanisms of action. Reasons for increased germination after exposure to music offered in the literature are, among others, an increase in the concentration of metabolites (Chowdhury & Gupta, 2015); changes in the elastic modulus and the viscosity coefficient of the plasmalemma (Wang et al., 2001); an increase in intercellular Ca2+ (part of the secondary messenger system) that can change the activity of membrane-bound enzymes (Wang et al., 2002; Teixeira da Silva & Dobránszki, 2014); and altering the secondary structure of cell wall proteins by changing amide I and amide II bonds (Chowdhury et al., 2014). Miranda (2013) provides an overview of research literature on the biological, psychological, and social effects of music on people; students could also be asked to focus on this aspect as part of their projects.

Project-Based Learning to Explore the Influence of Music on Seed Germination (Hands-on Lab Investigation) & on People (Literature Study)

Krajcik and Shin (2016, p. 276) identify six features of project-based learning (Table 2), and it is recommended that you structure this investigation taking cognizance of these.

Table 2.
Suggestions for how to structure this project, based on the key features of project-based learning identified by Krajcik and Shin (2016, p. 276).
Key FeatureHow This Could Be Addressed in the Classroom
Start with a driving question, a problem to be solved. I suggest that students work in a cooperative learning fashion, in small groups (see De Beer & Petersen, 2017b). Each group should formulate a driving question or hypothesis for the investigation, for example:
  • Is there any scientific evidence that supports the Maranao custom of exposing seeds to music to enhance germination?

  • How do different music genres influence seed germination?

  • Are all seeds (of different plant species) equally sensitive to music?

  • What are the influences of different sound volumes and times of exposure to music on seed germination?

  • If you broaden the scope of the project to include humans, a driving question could be “What are the biological, psychological, and social effects of music on people?”

 
Focus on the key standards and outcomes that should be achieved. Students should engage with key standards. In this scientific inquiry, students will learn more about the cell; biological evolution; matter, energy, and organization in living systems; and behavior of organisms. 
Students should explore the driving question by participating in scientific processes. Students will, when planning their investigations, identify all dependent and independent variables. Based on their driving question, they might focus on how different plant species respond to music or, alternatively, how bean seeds (Phaseolus vulgaris) germinate when exposed to different genres of music. 
There should be engagement in collaborative activities to find solutions to the driving question. Students should also engage with other groups (who might have different experimental designs) and, in the beginning stage of the project, critique the experimental designs of other groups. 
Student learning is scaffolded with learning technologies. Encourage students to engage with literature available on the Internet on the influence of sound waves on cell structure. 
Students create an investigable project that addresses the driving question. Various options exist. You could arrange a class seminar, where all groups present their findings. Alternatively, students can make posters for a class poster display. Students could also be asked to write up their projects in the form of research papers. 
Key FeatureHow This Could Be Addressed in the Classroom
Start with a driving question, a problem to be solved. I suggest that students work in a cooperative learning fashion, in small groups (see De Beer & Petersen, 2017b). Each group should formulate a driving question or hypothesis for the investigation, for example:
  • Is there any scientific evidence that supports the Maranao custom of exposing seeds to music to enhance germination?

  • How do different music genres influence seed germination?

  • Are all seeds (of different plant species) equally sensitive to music?

  • What are the influences of different sound volumes and times of exposure to music on seed germination?

  • If you broaden the scope of the project to include humans, a driving question could be “What are the biological, psychological, and social effects of music on people?”

 
Focus on the key standards and outcomes that should be achieved. Students should engage with key standards. In this scientific inquiry, students will learn more about the cell; biological evolution; matter, energy, and organization in living systems; and behavior of organisms. 
Students should explore the driving question by participating in scientific processes. Students will, when planning their investigations, identify all dependent and independent variables. Based on their driving question, they might focus on how different plant species respond to music or, alternatively, how bean seeds (Phaseolus vulgaris) germinate when exposed to different genres of music. 
There should be engagement in collaborative activities to find solutions to the driving question. Students should also engage with other groups (who might have different experimental designs) and, in the beginning stage of the project, critique the experimental designs of other groups. 
Student learning is scaffolded with learning technologies. Encourage students to engage with literature available on the Internet on the influence of sound waves on cell structure. 
Students create an investigable project that addresses the driving question. Various options exist. You could arrange a class seminar, where all groups present their findings. Alternatively, students can make posters for a class poster display. Students could also be asked to write up their projects in the form of research papers. 

My Own Investigation: An Exemplar for Students to Critique & to Whet Their Appetite for the Project

I decided to use bean seeds in my investigation and to have a control (seeds not exposed to sound waves) and two experimental treatments: one where seeds were exposed to classical music (Mozart), and one where seeds were exposed to Vedic chants. While conducting the experiment, I had to consider numerous variables (e.g., uniformity in light conditions, since the seeds were placed in different rooms, with different amounts of sunlight). I decided to place the seed trays in cardboard boxes (Figure 1A). The experimental seeds were exposed either to Mozart or to Vedic chants for 24 hours per day (by using the “repeat” option on the CD player). There was an increased rate of germination in the two experimental treatments compared to the control.

Figure 1.

The influence of Mozart and Vedic chants on seed germination. (A) Experimental setup: seed trays placed in boxes, with openings facing the CD player. (B) Control seeds (no exposure to sound) and experimental seeds (exposed to Mozart or Vedic chants). (C) Day 6: germination is seen in experimental seeds, with no germination in control seeds. (D) Day 8: only two of the 10 control seeds have germinated, as compared to four seeds in each of the experimental treatments.

Figure 1.

The influence of Mozart and Vedic chants on seed germination. (A) Experimental setup: seed trays placed in boxes, with openings facing the CD player. (B) Control seeds (no exposure to sound) and experimental seeds (exposed to Mozart or Vedic chants). (C) Day 6: germination is seen in experimental seeds, with no germination in control seeds. (D) Day 8: only two of the 10 control seeds have germinated, as compared to four seeds in each of the experimental treatments.

Student Data: Student Posters Designed during the Cooperative Learning Activity

A group of 32 life science students in an 11th-grade class, working in groups of four, were asked to design a poster in which they planned an experimental procedure to test whether music influences seed germination. Two examples of the posters are shown in Figure 2. In one poster (Figure 2B), students identified independent variables (different types of instruments and how they sound), dependent variables (rate of seed germination), and controlled variables (light intensity, temperature, water, etc.). This was an interesting departure from simply exposing seeds to music (instead comparing exposures to individual instruments). Another group decided to test whether different species of seeds are equally sensitive to music, and they used four different types of seed for the investigation. Another group decided to compare the music sensitivity of monocotyledonous and dicotyledonous seeds.

Figure 2.

Examples of student posters.

Figure 2.

Examples of student posters.

Apart from fostering creative thinking, it was clear that affective outcomes, such as student interest, were achieved in this activity. Each student was asked to describe their emotional response to their involvement (summarized in Figure 3).

Figure 3.

Word cloud summarizing students' emotional responses to their involvement in the activity. The majority of students indicated that they experienced the activity as “interesting” and “challenging.”

Figure 3.

Word cloud summarizing students' emotional responses to their involvement in the activity. The majority of students indicated that they experienced the activity as “interesting” and “challenging.”

Assessment

As shown in Table 2, various assessment opportunities exist, such as a class seminar in which all the groups do short presentations of their findings, a poster display, or student reports in the form of journal articles. The following questions could be used to guide student reflection on the inquiry:

  • Is there a sufficient body of scientific literature showing that music could enhance seed germination? How rigorous were the experiments performed (e.g., in terms of the number of seeds used or the number of repetitions)?

  • Which biological explanations can be offered for enhanced germination of seeds exposed to music?

  • What were the dependent and independent variables in your experimental design?

  • What problems did you experience with your research? If you had to repeat the project, what changes would you make to the experimental design?

  • Sonication is a process in which sound waves are used to agitate particles in solutions. What applications exist for sonication in modern industry?

  • What did you learn from the literature regarding the biological, psychological, and social effects of music on people?

Conclusion

A growing volume of research demonstrates the merit of indigenous knowledge and practices, such as those of the Maranao people in the Philippines, who expose seeds to music in order to improve crop yields. Although the biochemistry is not yet fully understood, it appears that music has an effect on the viscosity of the plasmalemma and the availability of intercellular Ca2+, which influences the activity of membrane-based enzymes.

This inquiry could be effective in enhancing students' interest in botany. From the literature it appears that certain forms of music (e.g., classical and devotional music) are more effective than others (e.g., acid rock). It could also assist students in critically reflecting on experimental designs. This is a particularly complex investigation, given the large number of variables involved. The experiment described above (Figure 1) can be used as an exemplar that students could interrogate in terms of scientific rigor (or lack thereof). When compared to more rigorous studies, such as the one by Creath (2002), it should be clear to students that a lot can be done to improve the experimental design described here. Creath (2002) obtained data from the germination of 3600 seeds over a total of 14 cycles of five experiments (compared to 30 seeds with only one cycle, as in my investigation). The students could also critically reflect on their own experimental designs. This learning activity also sensitizes students about the quality of journals in which research are printed, and to distinguish between peer-reviewed journals and grey literature/questionable journals.

As noted, this inquiry could be expanded to include a focus on the influence of music on people. The literature shows that the biological effects of music on humans include the activation of neurotransmitters and the alteration of stress hormones (Miranda, 2013).

By packaging the curriculum content and learning activities in a format that accommodates the real interests of adolescents, we might see both cognitive and affective gains in the biology classroom. The data obtained from the poster activity clearly illustrate such affective gains.

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