No abstract

Modern agriculture poses ecological problems and opportunities, which defy simple democratic reform without an educated citizenry. Developing an educated citizenry can be accomplished by further developing agricultural literacy in elementary education. While benchmarks for agricultural literacy have been produced, relatively little attention has been focused on how students conceptualize the food system. Using Piaget's theories of schemata development, this study compared students' understanding of agriculture to grade-specific benchmarks for agricultural literacy to uncover relationships between students' backgrounds, experiences, and understandings of the agri-food system. The population consisted of 18 elementary students from Long Beach, California. Data was collected via 45-minute semi-structured interviews. While almost half had been on field trips to a farm or visited a garden, none had ever grown a plant or raised an animal. Students' ideas about agriculture were often guesses, underdeveloped, or contradictory to expert conceptions. Students failed to convey an understanding of the types and variety of farms, the purpose of farms, or the cultural practices dominating conventional farming. Results suggest that educators should focus on existing underdeveloped schemata to help learners construct viable ideas about modern agriculture supported by contextually rich formal and informal agricultural experiences.

Observations on the ontogeny and diversity of salamanders provided some of the earliest evidence that shifts in developmental trajectories have made a substantial contribution to the evolution of animal forms. Since the dawn of evo-devo there have been major advances in understanding developmental mechanisms, phylogenetic relationships, evolutionary models, and an appreciation for the impact of ecology on patterns of development (eco-evo-devo). Molecular phylogenetic analyses have converged on strong support for the majority of branches in the Salamander Tree of Life, which includes 764 described species. Ancestral reconstructions reveal repeated transitions between life cycle modes and ecologies. The salamander fossil record is scant, but key Mesozoic species support the antiquity of life cycle transitions in some families. Colonization of diverse habitats has promoted phenotypic diversification and sometimes convergence when similar environments have been independently invaded. However, unrelated lineages may follow different developmental pathways to arrive at convergent phenotypes. This article summarizes ecological and endocrine based causes of life cycle transitions in salamanders, as well as consequences to body size, genome size, and skeletal structure. Salamanders offer a rich source of comparisons for understanding how the evolution of developmental patterns has led to phenotypic diversification following shifts to new adaptive zones.

Agricultural literacy of K–12 students is a national priority for both scientific and agricultural education professional organizations. Development of curricula to address this priority has not been informed by research on what K–12 students understand about the agri–food system. While students’ knowledge of food and fiber system facts have been studied, in–depth research into broader student understandings of the system have largely been ignored. This study employed semi–structured interviews to compare urban elementary students' understandings with nationally developed benchmarks for agri–food system literacy. Findings indicate that no participant had ever grown their own food, raised a plant, or cared for an animal. Participation in school fieldtrips to farms or a visit to a relative’s garden were the most frequently mentioned agricultural experience. Participants could readily name common food items, but could not accurately elaborate on the origins of common foods. Post–production activities, like food processing, were not well understood. Students’ agriculturally related experiences did not appear to influence their understanding about where food comes from or what happens to food as it travels from farm to plate.

Nationally, both science and agricultural education professional organizations have identified agriculture as a fundamental technology to be studied by students, with the goal of achieving an understanding of the agri‐food system necessary for democratic participation. Benchmarks representing the content that K–12 children need to understand about the scientific and technological underpinnings of the agri‐food system have been developed by agricultural and science educators. However, the benchmarks were developed without empirically based evidence on what existing agri‐food system knowledge students held. This study examines students’ understandings about science and technology concepts underpinning benchmarks for agricultural literacy. Urban upper elementary student concepts of the origins of food, the selection of plants and animals used for production, how people living in harsh environments obtain crops, and the prevention of food spoilage were probed. Using Piaget's theory of schema development, students’ understanding of agricultural technology were compared to grade‐specific benchmarks for agricultural literacy and examined for relationship to students’ backgrounds and experiences. In comparison to the benchmark goals for the age group, informants’ schema for the role that science and technology plays in the agri‐food industry was nearly nonexistent. This study suggests that existing agricultural literacy benchmarks, as designed, may not be age and/or developmentally appropriate. Additional suggestions indicate that underlying sub‐concepts needed for learner understanding may only be loosely connected to any meaningful experience of urban elementary students.