Paula C. Jackson

Physiological Ecology of Vascular Plants

The Yucatan Peninsula has opposing gradients of precipitation and evaporation from north to south: as precipitation increases, evaporation rates decrease. Also, due to bedrock composed primarily of limestone, the area presents high porosity and rainfall infiltrates quickly, resulting in no superficial runoff. Natural disturbances such as hurricanes and fires are also common. The interaction of these factors has created a mosaic of environmental conditions that has given rise to a series of physiological adaptations in the plant species of the area. This chapter focuses mainly on the morphophysiological responses and adaptations of native plant species of the Yucatan to natural conditions, and on how plants respond to environmental factors at the level of the individual, species, population and/or functional groups. In this chapter, species were grouped according to their metabolic pathway (C3 species or crassulacean acid metabolism species (CAM)), and discussed based on adaptations to limiting resources: water, nutrients, temperature, and light. For C3 species only trees were included, and studies incorporated in this section spanned from plant establishment, growth, water use and water relations, alternative water sources, and carbon and nutrient flow. For the section on CAM the focus was on the factors that affect CAM plants in the microenvironments in which they occur. Other issues analyzed include plant physiological responses to natural disturbances, the potential impact of climate change on plant populations, and gaps in information as well as additional perspectives of study.

Transforming undergraduate biology learning with inquiry-based instruction

We developed an inquiry-driven course to enable students to develop skills they need to effectively use large amounts of information available on the Internet (including evaluating information, synthesizing, and collaborating) and engage more deeply with science content. Student teams collaborated to construct a scientific question, research what was known at the time about the answer to their question, and generate a final product to communicate their findings using multimedia on a web-based platform. Course iterations consistently yielded at least one group of students who transformed from struggling to successful, which led us to use content and narrative analysis of case studies to distinguish group types. We found three group types: High Engaging (HE), Transformed (T), and Low Engaging (LE). Each group type succeeded in creating a final web-based project. However, the projects created varied in level of cognitive depth between groups and indicated traits common to each group type. We outline similarities and differences among group types, use differences in groups to identify mechanisms that could facilitate deeper levels of cognitive engagement, and make recommendations about how educators can enable an increase in the number of highly engaged students in this type of inquiry-based course.