Habitat fragmentation can alter the conditions of natural plant populations, introducing novel selective pressures. The ability of a population to respond to environmental change can be inferred by assessing the population’s genetic diversity and the heritability of traits thought to be under selection.
Identifying factors that shape the spatial distribution of genetic variation within and among natural populations is crucial to understanding many population> and landscape>level processes. In this study, I characterize the strength and extent of spatial genetic structure in Oenothera harringtonii (Onagraceae), an insect>pollinated, gravity>dispersed herb endemic to the grasslands of...
The tallgrass prairie once dominated much of the mid-western United States. Today, this highly productive system has been severely reduced, contributing to an array of environmental problems. The recent renaissance in natural area restoration and stewardship of the tallgrass prairie in the Chicago Wilderness region (Illinois, USA), especially in the...
Nitrogen (N) deposition can alter belowground microbial communities, especially ectomycorrhizal (ECM) fungi, resulting in a reduced ability of associated trees to access organic nutrients. This study tested whether N addition decreases ECM species richness and shifts ECM species composition across spatial scales in a subtropical slash pine (Pinus elliottii) plantation...
The environmental and plant physiological correlates of plant growth and reproductive effort in the locally threatened orchid, Cypripedium candidum Muhl. ex Willd were examined in the context of a conceptual model of demographic and reproductive trade-offs, focusing on three Illinois populations. This study addresses the current status and long-term trends...
Plant-aphid systems provide a valuable opportunity for studying the ecological consequences of land use change for interacting species. The North American tallgrass prairie has undergone severe reduction and fragmentation due to agricultural development. The prairie perennial Echinacea angustifolia, a model system for studying population-level effects of habitat fragmentation, hosts a...
The introduction of non-native pests in general, and invasive plants in particular, has been receiving increasing interest by scientists, environmental groups, and to a certain extent the general public. Deleterious effects from the release of such alien species include threats to the environment, national economies, and even human health. The...
Underutilized crops have the potential to economically benefit developing countries and to improve global food security. Breadfruit (Artocarpus altilis, Moraceae) is one such crop that can provide essential nutrients and requires relatively low-energy input to maintain compared to major crops. Humans have selected for many cultivars of breadfruit since its...
With increasing urbanization and creation of novel habitat types, green roofs can provide usable habitat for many species. To date, most research on green roofs has focused on minimizing the environmental impacts of buildings but little is known about the ecological services they provide. Previous research has shown that although...
Hybridization is an important evolutionary pathway to genetic diversity, fitness, and ultimately to the emergence of new species. In contrast, hybridization between a native and an introduced species can lead to a loss of locally adapted gene complexes and ultimately to the extinction of the native. In the last decade,...