Evolutionary concepts in primary school curriculum standards
No comprehensive review or comparison of international primary school curriculum standards regarding their integration of evolutionary concepts appears to exist (one attempt is e.g., Campos & Sá-Pinto, 2013, additional file 1). Nonetheless, there are indications that there is a high degree of variation across countries. For example, in the US the Next Generation Science Standards include evolutionary concepts across grades 1-4 (NGSS Lead States, 2013). Grade 1 includes the core ideas of “Inheritance of Traits” and “Variation of Traits”; grade 3, the core ideas of “Evidence of Common Ancestry and Diversity”, “Adaptation”, “Inheritance of Traits”, “Variations of Traits”, and “Natural Selection”; and grade 4, the core idea of “History of Planet Earth”. In Germany, however, evolutionary concepts are hardly included in current primary school (grades 1-4) curriculum standards. The German primary school subject of Sachunterricht is a multidisciplinary subject integrating natural science, social science, geography, history, cultural and technical perspectives (GDSU, 2013). In the national framework for the German Sachunterricht (GDSU, 2013) as well as across Sachunterricht curricula of 16 German states, the terms evolution, inheritance, selection, do not appear at all. However, a few evolutionary concepts appear implicitly or explicitly in standards and teaching materials. Most but not all curriculum standards make reference to “adaptation” or “adaptedness”. However, the term adaptation is often used in at least two ways (in the evolutionary sense, as well as in the sense of adapting one’s behavior to certain circumstances), and it is not made clear how exactly students might attain or relate to these diverse uses of adaptation as a concept within biology and other disciplines. Four state curricula make reference to the “stone age”, one curriculum makes reference to fossils and one makes reference to family trees.
Given the sporadic to non-existent explicit treatment of evolution in current German primary school curricula, one might assume that primary school teachers do not need to be equipped with any knowledge and competencies regarding the teaching of evolution. Here we argue that this stance is misguided for several reasons.
One reason evolution should be taught in primary school is the potential of reinforcing misconceptions. As has been noted by others (Campos & Sá-Pinto, 2013; Prinou et al., 2011), treating the concept of adaptation or adaptedness of traits without also exploring the (evolutionary) causes for this adaptedness runs the danger of leaving misconceptions unchallenged or even reinforcing them, such as inadequate teleological or creationist beliefs. It also hinders students in understanding and evaluating possible impacts of human action on the environment and on species.
For example, in the German national framework for Sachunterricht (GDSU, 2013), we find an example lesson on the shapes of seeds. The text states ”Questions emerge regarding the causes or purpose that these different shapes of seed wings have. Why do some seeds have wings, others not? Why do some seeds have big wings, others small wings?” (GDSU, 2013; p. 97, own translation from German, emphasis added). However, while asking for “causes”, the text does not include the treatment of evolutionary causes, particularly random variation and natural selection, to help students understand the mechanism that led to these currently observable functional traits. We observe in the framing a muddling of cause and function/purpose that, within the evolution education literature, is often regarded as highly problematic as it reinforces problematic forms of teleological thinking (e.g. (Kelemen, 2012). At the same time the lesson in fact offers bits of text and explanations that go a long way towards providing answers to the question of evolutionary cause, yet the evolutionary logic of these pieces of information is not made explicit to teachers nor students.
Another reason to integrate evolution education in primary grades is the aforementioned role of evolutionary concepts in understanding the natural world - they are lenses that help to understand and relate a variety of phenomena. Evolutionary concepts should thus be woven in and addressed across themes in instruction. As others have similarly highlighted (e.g. (Campos & Sá-Pinto, 2013; Russell & McGuigan, 2019b)), many concepts and learning goals in primary school curricula can in fact be connected into the goals of evolution education (i.e. developing conceptual understanding of evolutionary concepts), but this may require a more explicit evolutionary framework such that teachers and students can come to understand the evolutionary logic of the phenomena they are exploring.
Similarly, an increasing diversity of resources exist that are exposing younger children to evolutionary ideas. For example, we have collected a database of more than 80 children's books across several languages that cover various evolutionary themes (see supplementary materials, additional file 1). However, these books may not necessarily present information in a way that is congruent with current best practice in evolution education and may in fact rather reinforce various misconceptions (Adler et al., in review).
Thus, teachers need to be enabled to critically assess the usefulness of materials available to them in their context regarding the development of scientific understandings. At the same time, teachers need to be enabled to make use of local opportunities such as student interests and questions, curriculum themes and learning goals, current events and media, informal learning places like zoos and museums, and other locally available materials that provide (possibly implicit) opportunities for teaching evolutionary concepts.
For these reasons, we argue that primary school teachers need to be enabled to develop pedagogical content knowledge (PCK) to teach evolutionary concepts, not just in a separate unit about evolution and with a concrete and prescribed set of topics and instructional methods (as, e.g. indicated by Buchan et al., 2020), but across a range of phenomena and using a diversity of methods, flexibly adapted to their context. This also includes developing teachers’ ability to ''see'' evolutionary concepts in the curriculum and in teaching materials, even if they are not explicitly stated in wording, and to derive “teachable moments” towards conceptual understanding of evolutionary concepts and for addressing possible misconceptions. This identified need represents one of the main rationales for this study.
Pedagogical Content Knowledge for Teaching Evolution in Primary School
Teacher professional knowledge is usually conceptualized as consisting of several domains, including content knowledge (CT, of a subject or topic or concept), pedagogical knowledge (knowledge regarding the nature of teaching and learning) and pedagogical content knowledge (PCK; knowledge about curriculum goals, student understandings and learning difficulties, instructional strategies, and assessment related to a subject, topic or concept; Magnusson et al., 1999). PCK has also been further differentiated into collective, personal, and enacted PCK (Carlson et al., 2019).
Various questionnaire methods have been developed to assess evolution understanding of high school and undergraduate students (see Kuschmierz et al., 2020; Mead et al., 2019 for reviews). Such assessment tools are also used to assess CK of pre-service and in-service teachers. A recent and comprehensive assessment instrument is the Knowledge About Evolution 2.0 instrument (KAEVO 2.0) which integrates components of previous questionnaires and thus aims to cover a diversity of evolutionary themes and concepts (Kuschmierz, Beniermann, et al., 2020). Kuschmierz et al. (2021) report on a study using the instrument across 26 European countries with first-year university students enrolled in biology-related as well as non-biology related programs. Authors found that students across countries had a rather low knowledge of evolution, with 47% of students in biology-related programs and 76% of students in non-biology-related programs categorized as “Very low knowledge”. Torkar & Šorgo (2020) used part of the KAEVO 2.0 to assess Slovenian pre-service primary school teachers’ CK and also found very low levels of knowledge. In the current study, select questionnaire items of the KAEVO 2.0 were included in the (second) module design as formative assessment and discussion tools.
Various studies also clarified or assessed PCK around teaching evolution. Ziadie & Andrews (2018) reviewed the extent of collective PCK resulting from peer-reviewed literature on the teaching of evolution in high school and undergraduate level, highlighting certain knowledge gaps. While no such review appears to exist regarding collective PCK on the teaching of evolution at the primary school level, aspects of PCK have been explored or reviewed in a number of studies. For example, Bruckermann et al. (2020) reviewed young children’s (up to 7 years) pre-conceptions and potential learning difficulties about evolutionary concepts of variation, inheritance, and natural selection. Many studies have contributed instructional strategies for the teaching of evolutionary concepts in primary school, summarized in table 1. Several learning progressions have also been proposed on teaching evolutionary concepts in primary school (Catley et al., 2005; Lehrer & Schauble, 2012; Russell & McGuigan, 2019a), together with proposed instructional strategies.
Table 1. Overview of methods to teach core evolutionary concepts in primary school synthesized from existing literature. (see end of document)
Thus, it can be said that the evolution education literature is making progress in establishing elements of collective PCK regarding the teaching of evolution in primary school. This literature can increasingly inform primary science teacher educational programming towards the development of teacher personal PCK. The literature reviewed here, as well as further English and German language publications and materials around teaching evolutionary concepts in primary school, were thus used to inform the module design and/or included as content and materials (see supplementary materials, additional file 1).
Despite these advances in collective PCK, not many studies exist around developing and evaluating primary school teachers’ personal and enacted PCK on teaching evolution. Asghar et al. (2007) explored the attitudes and knowledge of pre-service primary school teachers in Canada around teaching evolution through surveys and interviews, and concluded that study participants lacked sufficient CK and PCK about evolution despite evolution being integrated in the curriculum. Similarly, Billingsley et al. (2019) explored the attitudes of pre-service primary school teachers in the UK through a survey and found that the majority of participants had a positive attitude about the importance of teaching evolution in primary school and the recent inclusion of the topic in the English 6th grade curriculum, but only a quarter agreed that they had an adequate understanding of evolution to teach it.
Overall, PCK on evolution of mostly secondary in-service and pre-service teachers has been assessed using survey instruments (e.g. Fischer et al., 2021; Großschedl et al., 2015, 2019) as well as interviews, observations, and analysis of artifacts (e.g. Borgerding et al., 2015; Bravo & Cofré, 2016; van Dijk, 2009). In this study, qualitative and quantitative methods were used to assess participant PCK, particularly through the analysis of PCK elements in participant artifacts and questionnaire responses (see methods).
Opportunities for teaching evolution across the primary school curriculum
Within the larger design-based research project that this study is part of (Hanisch & Eirdosh, 2020), the rationale for teaching evolutionary concepts extends to the development of social-emotional competencies and transferable understandings of human behavior and culture. Thus a further aim of the review of literature was to identify opportunities to expand the teaching of evolutionary concepts in primary school beyond the natural domain and to connect to curriculum goals and instructional methods in the social, cultural and technical domains as well as in the domain of social-emotional learning.
Connections to curriculum goals in social - cultural and technical education
Evolutionary concepts have increasingly informed and shaped fields beyond biology, particularly with the emergence of the field of cultural evolution (Mesoudi, 2011). Overall, the theme of cultural evolution does not yet seem to be widely integrated in evolution education standards and practice and its potential remains relatively unexplored in evolution education (Hanisch & Eirdosh, 2020; in review). One might also think that cultural evolution is too advanced a theme for primary school. However, the literature review revealed that a variety of approaches and materials exist that indicate that even primary school aged children are already exposed to such ideas, and that they may hold significant learning potential. Thus, cultural evolutionary concepts may productively connect to curricular themes related to technology and culture (which are also included in the German Sachunterricht).
One primary school evolution education material that includes cultural evolution is the EvoKids textbook by Graf & Schmidt-Salomon (2017). In fact, the book includes a lesson plan for “Evolution of a paper plane” (p. 73 ff.) within the section of mechanisms of evolution, meant to help students understand the process of adaptation by natural selection through the analogy with successive improvements and selection of paper plane designs by trial-and-error. Interestingly, the “Evolution of a paper plane” lesson plan is not included within the book’s section on cultural evolution and no reference is made to the cultural evolutionary dynamics of the activity. At the same time, this activity is in fact equivalent to the paradigm of transmission chain experiments in cultural evolution (Mesoudi & Whiten, 2008). For example, Caldwell & Millen (2008) used this paradigm and developed experiments around the successive improvement of paper planes and “spaghetti towers” with participants aged 11 years and above to study cultural evolutionary processes. Similarly, Morgan et al. (2015) studied the role of teaching and language in the transmission of stone tool making. Their experimental setup in part resembles the games of Chinese whispers or Charades, which equally highlight the function of human language for the transmission of cultural information.
Furthermore, themes and instructional methods in evolution education usually focus on genetically inherited biological traits and may even discourage the discussion of other traits and mechanisms of their transmission (e.g. Campos & Sá-Pinto, 2013). In this regard, framings can sometimes be problematic in terms of reinforcing genetic determinism (and with possible implications for social-emotional development). For example, in Graf & Schmidt-Salomon (2017), when introducing the concepts of variation and inheritance, the text reads “What would it be like if we all looked exactly the same, and had the same hobbies and skills? (...) The fact that each one of you has different features is to do with your body's cells storing different hereditary information. Half of this comes from your mother and half from your father.” It seems problematic to frame complex traits like hobbies and skills as being caused exclusively by genes (and hence, predetermined and difficult to change).
At the same time, there are indications that primary school aged children can be supported in distinguishing between different kinds of traits and their biological and cultural forms of transmission. Moya et al. (2015) showed that 4-10 year old children across cultures (Peru, Fiji, USA) think most traits are biologically transmitted from parents, but by middle childhood (9 years and above), children increasingly differentiate between traits that are biologically inherited (such as morphological traits) and traits that are culturally inherited from parents or the social environment (such as knowledge and beliefs). It is an open question how such insights and methods might inform instructional strategies towards an understanding of biological and cultural inheritance in evolution education.
Connections to social-emotional learning goals
Another relatively unexplored dimension of teaching evolution, in primary as well as secondary school, is its relation to social-emotional learning and competencies such as growth mindset, self-regulation, perspective-taking, and cooperation.
The literature review suggests that, often, examples of themes and instructional methods in primary evolution education (as well as in secondary education) focus on the role of competition, predator-prey dynamics, and individual-level natural selection (e.g. most of the literature in table 1). Conversely, the evolution of cooperation is much less of a focus and may be perceived as a topic for advanced evolution education (see also Hanisch & Eirdosh, 2022; Ziadie & Andrews, 2018). However, cooperation is an important factor in the evolution of many species including humans. We argue that understanding the role of cooperation in our species can be a core component of developing cooperation competencies (see also Hanisch & Eirdosh, 2021, 2022). In the course of module development, we found that simulation games to teach the logic of natural selection can be modified to teach the evolution of cooperation, and they thus resemble cooperation games that are used in behavioral experiments to study human social behavior (e.g. Fehr & Gächter, 1999). Various cooperation games are often already used in primary and secondary education to develop cooperation competency and an understanding of the need for cooperation in society (e.g. Mann & Stapp, 1982), and these can be extended to explore the functions of various human behaviors (e.g. communication, sense of fairness, empathy) as well as the evolutionary origins of these traits. Thus, an instructional material that emerged during module design was a cooperation game that simulated a stone age collective hunt and the challenges of cooperation and collective action inherent in this situation, based on the game theoretic models of the “stag hunt” and public goods game as collective action problems (Obach, 2003; Skyrms, 2004), and highlighting how cooperative abilities are advantageous in such situations.
Implications for social-emotional learning also present themselves when teaching foundational evolutionary concepts like variation and natural selection. For example, an approach to help students see within-species variation is to explore variation among students in the class (e.g. Campos & Sá-Pinto, 2013, Buchan et al., 2020, see table 1). An issue that has apparently not been addressed so far is the ethical and social-emotional implications of doing this. After all, it can be problematic to highlight variations in traits like weight or skin color. Additionally, it is scientifically incorrect and pedagogically problematic to connect trait variation among students to the idea of “adaptation” and “natural selection”, with potentially harmful implications that some students in class are “better adapted” than others. This issue was explicitly addressed in the module in the form of a structured group discussion asking - why might it be problematic pedagogically to highlight variations among students in class, and how might one deal with this in the classroom. Overall, when exploring trait variation in the classroom it might be important to also point out the fact that not all traits have functions that are relevant for survival. Furthermore, it might also be important and helpful to highlight two factors that are responsible for why variation in many traits among humans today can not anymore be considered under natural selection in the strict sense - due to the fact that humans have the capacity for empathy for others, and additionally (and unlike other animals that also have the capacity for empathy), due to the fact that we have culture and can therefore create conditions that do not create disadvantages for others (as an example the teacher could highlight the fact that she was wearing glasses). Highlighting this aspect may be important especially in classrooms with diverse students.
Outside of the fields of science and evolution education, approaches to developing students’ wellbeing and social-emotional competencies also exist that in fact integrate evolutionary concepts. For example, learning about emotions and ways to regulate them is usually a topic considered outside of the domain of evolution or science education (e.g. in the German primary school curriculum, the theme of emotions is situated in the subject of Ethics). However, such lessons can be enhanced with evolutionary concepts - such as exploring concepts of emotion in other (related) animal species or the functions that emotions have for animals and four our own everyday lives and well-being. In this regard, Castano (2012) developed and evaluated a science education intervention for fourth-graders to promote “compassionate attitudes towards animals through gaining an understanding of their needs, emotions, capacities, current situations and their similarities with humans”, and highlighted that “science education with a focus on promoting understanding and compassion towards animals could contribute to the amelioration of aggression in schools”. Furthermore, a glance at primary school teaching materials about emotions showed potential for highlighting evolutionary concepts. For example, philosophical questions such as “what if there were no emotions [fear, anger, sadness …]” can be used to highlight the functions of emotions. The instructional strategy of stories about the natural selection of traits (e.g. Kelemen et al., 2014, see table 1) can be employed to develop stories about the natural selection of certain emotions. The Pixar Movie Inside Out (Docter & Del Carmen, 2015), developed in collaboration with the (cross-cultural, developmental, and evolutionary) psychologist Dacher Keltner, has also spurred a range of teaching materials that help to highlight the functions and interactions of emotions, language, identity, and well-being, which can serve as vehicles to reinforce understanding of evolutionary concepts.
Some materials and approaches for encouraging health-related behavior also imply the use of evolutionary concepts. In the German framework for Sachunterricht, under the theme of health, we find an example lesson in which students compare the lifestyle and healthy behavior of humans in the stone age with the lifestyle and healthy behavior of children in the modern world, with the aim to help students understand and develop healthy behaviors such as exercise and diet (GDSU, 2013, p.146). This lesson implicitly uses the concept of evolutionary mismatch as a teaching moment to motivate behavior change (see also Basile et al., 2021; Sherry, 2019). Evolutionary mismatch can be defined as “a negative consequence that results from a trait that evolved in one environment being placed in another environment”(Lloyd et al., 2011). However, this concept itself is not made explicit (to teachers or students), thus not allowing teachers and students to use this lesson in order to develop a more abstract and transferable understanding of this phenomenon which they could then use to understand many other potential instances of evolutionary mismatch that might impact human well-being and sustainable development in today’s world (Baumeister & Robson, 2021; Ehrlich & Blumstein, 2018; Li et al., 2018; Rees, 2010).
In the EvoKids textbook by Graf & Schmidt-Salomon (2017), another important possible instance of mismatch in our species is implicitly explored within the unit on human and cultural evolution. The text points out the role of group life, group cognition and group markers in the evolution of our species, relates this aspect to students’ own experience, and then asks the simple question “Are these things an advantage or could they also be dangerous?” (p. 99), through which an understanding can emerge that our evolved group-thinking may lead to problems such as social conflict today.
These existing lesson materials served as an indication that the concept of mismatch might be productively integrated in the module design towards the discussion of a variety of instances of potential mismatch in our species and ways to overcome them.
A further approach that integrates evolutionary concepts and was developed to enhance student mental health is the DNA-V model developed by Hayes & Ciarrochi, 2015). It is based in the field of contextual behavioral science, which integrates interdisciplinary evolutionary theories towards an understanding of human cognition and behavior and the development of methods that enhance human flourishing (Hayes et al., 2017). Central within contextual behavioral science is the view of individual learning and behavior change as evolutionary processes through mechanisms of variation and reinforcement, the view that due to language and symbolic thinking, humans can get “stuck” (often framed as an instance of possible mismatch) and thus need to be enabled to rediscover and practice processes of mindful and flexible behavior change in service of their self-identified values.
The DNA-V model has been developed specifically for younger people to help them distinguish and practice different skills of their mind towards the development of psychological flexibility: the Discoverer stands for the skill of flexible behavior change as a source of behavioral variation; the Advisor stands for our “inner voice” which is shaped by past evolution and experience and may give helpful or unhelpful advice (related to the concept of mismatch); Values are like “selection pressures” for those kinds of behaviors that serve valued living; and the Noticer stands for the skill of mindful awareness of all these experiences. Hayes & Ciarrochi (2015, p. 54-56) propose an activity about the evolutionary origins and functions of human language (our Advisor) and its negativity bias (i.e. our inner voice is often negative and warning us of potential problems) that shares elements with natural selection stories (Kelemen et al., 2014) by integrating variation, function, differential reproduction, and inheritance over many generations. Similarly, the well-being curriculum for students aged 4-11 by Connect PSHE (2021), informed by the DNA-V model, uses images of cave men and questions to help children understand the evolutionary origins and functions of emotions, language and thoughts (Fig. 1).
Such instructional methods focusing on the evolution of traits relevant to social-emotional learning may contribute to both conceptual understandings of evolution and psychological flexibility. Porosoff & Weinstein (2019) and Dixon & Paliliunas (2017) propose further activities and instructional methods based on contextual behavioral science that were integrated in the module design as related to the integration of evolutionary concepts.
Thus, this informal review (summarized in Table 2) revealed that, besides the growing body of literature and collective PCK for teaching evolution in primary school science education, more and more opportunities exist to weave the teaching and learning of evolutionary concepts across a diversity of themes in the primary school curriculum, including towards the development of social-emotional learning. These emerging opportunities thus represent another core rationale for this design study.
Table 2. Opportunities and innovations regarding the teaching of evolution across the primary school curriculum beyond natural science. (see end of document)
In the following sections, we describe how these findings were integrated in the iterative development and evaluation of a module design.