ABSTRACT
This chapter is a theoretical and empirical synthesis of our past research on knowledge acquisition in the domain of evolutionary biology (Chinn & Samarapungavan, 2006; Samarapungavan, 2004; Samarapungavan & Malikowski, 1992; Samarapungavan & Wiers, 1994, 1997). Although the research reviewed here focuses on the scientific domain of evolutionary biology, I discuss our findings in terms of “theories of speciation” because a vast majority of our research participants have non-normative beliefs (i.e., beliefs that do not conform to current scientific theory) about the nature and origin of species. Our research is constrained by the guiding assumption that the structure of concepts and the nature of reasoning and learning vary across domains of knowledge (Carey & Spelke, 1994). A second assumption is that people (both children and adults) understand natural phenomena through the lens of explanatory frameworks (Samarapungavan & Wiers, 1997) constructed from a synthesis of their everyday phenomenological experiences as well as cultural information (Brewer & Samarapungavan, 1991; Carey, 1991; Gopnik & Wellman, 1994). The content and structure of such belief systems serve to organize and interpret experience. A vast body of empirical research has shown that children’s initial concepts of the natural world differ dramatically from scientific theories in their conceptual content (Carey & Spelke, 1994; Chi, Slotta, & de Leeuw, 1994; diSessa, 1993; Wiser, 1988; Vosniadou & Brewer, 1992, 1994; Samarapungavan, Vosniadou, & Brewer, 1996). Therefore, accounts of knowledge acquisition need to explain how people might come to acquire the formal scientific theories that are so distant from their initial representations of the world. Evolutionary biology serves as a paradigm case for exploring the factors that influence the course of conceptual development. Research indicates that even four-year-olds have concepts about the nature of biological species (Inagaki & Hatano, 2004; Kelemen, 2004). For instance, Kelemen (2004) suggests that children may be intuitively predisposed to construct design-based explanations for the origin of species. By elementary school, children also
develop ideas about mechanisms of speciation: how species originate, and whether and how they change over time (Evans, 2000; Samarapungavan & Wiers, 1997; Samarapungavan, 1997, 2004). In other words, children acquire beliefs about speciation even before they receive any formal biological instruction on the topic in school. To complicate matters, evolutionary theory is not necessarily the most prevalent or salient cultural account of speciation that is available to students through the course of their conceptual development (Brem, Ranney, & Schindel, 2003; Lawson & Worsnop, 1992; Ruse, 1988; Sinclair, Pendarvis, & Baldwin, 1997). Variants of creationism (Moreland & Reynolds, 1999) may be presented as competing explanations for speciation both informally (e.g., through conversations with parents or friends) and formally (e.g., in the course of formal religious instruction). The prevalence of competing cultural models for speciation also leads to variability in the extent and quality of formal instruction in evolutionary biology (Brem et al., 2003). Past research indicates that many adults reject evolutionary theory altogether and others, who are willing to entertain evolutionary explanations, show significant misunderstandings about many aspects of evolution (Bishop & Anderson, 1990; Brem et al., 2003; Chi, 2005; Clough & Wood-Robinson, 1985; Mazur, 2005; Samarapungavan & Malikowski, 1992; Sinatra, Southerland, McConaughy, & Demastes, 2003). The reasons for the current state of affairs with regard to the understanding of evolutionary biology are manifold and undoubtedly include socio-cultural factors such as religious belief (Mazur, 2005; Evans, 2001), the pedagogical treatment of evolution in formal schooling (Lerner, 2000), as well as personal predispositions such as openness to conceptual change (Sinatra et al., 2003). The research described here examines one set of factors: the interplay between domain-specific ontological and epistemic beliefs as children construct and revise their ideas about species and speciation. Specifically, we suggest that by elementary school, children construct explanatory frameworks in terms of which they think about species and speciation. The term “explanatory framework” is used to describe the system of beliefs that children draw upon to answer questions about speciation (see Samarapungavan & Wiers, 1997 for details). Explanatory frameworks are not fully pre-specified theories in that the core beliefs of a single framework may be compatible with a variety of specific solutions to problems of speciation. The frameworks are not necessarily parsimonious. Multiple mechanisms for speciation may be proposed within a single framework as long as these mechanisms are not mutually inconsistent and do not contravene the core beliefs of the framework. Historical theories of speciation have been characterized by a lack of parsimony. In The Origin of Species (1872, last edition) Darwin proposes mechanisms such as the modification of features through use, or by direct environmental influence, in addition to natural selection to explain speciation. One important aspect of explanatory frameworks is that they carry ontological and epistemo-
logical commitments that influence how novel problems are treated. In the next section, I will describe our findings with regard to naïve explanatory frameworks.
