The prairie grasses Andropogon gerardii and Sorghastrum nutans have seeds with awns that twist in response to changes in humidity. The humidity-sensitive, or hygroscopic, part of the awn twists, moving the bent, passive portion in an arc. This trait has been demonstrated to improve seedling recruitment in other grass species...
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...
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.
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...
This thesis discussed how motifs of height and depth in Black literature highlight Black characters’ inability to form positive racial identities. The thesis uses three canonical pieces of Black literature, Passing, Native Son, and Plum Bun, to demonstrate that Black characters who try to reimagine White space are forced into...
Pollination is a reproductive necessity in the majority of the world’s flowering plants. Pollen limitation threatens plant reproduction, particularly in self-incompatible species. Although assessing pollen limitation usually requires pollen supplementation experiments, alternative methods support the findings of traditional pollen supplementation experiments.
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...
Trees in urban areas offer ecosystem services like carbon sequestration, storm water attenuation, reduction of energy used in buildings and wildlife habitat. Cities invest substantial funds and resources to maintain a healthy urban forest, and much research has been done to improve its resiliency and sustainability. Studies have been done...
Cosmetic cracks are very common in structures, and most of the time they remain unnoticed and do not decrease the structural integrity. Although these cracks are unremarkable and barely noticeable, occupants become concerned about these cracks when construction occurs nearby. In order to investigate the true nature of these cracks,...