Prokaryotic microbes, commonly termed bacteria, are essential components of the ecosystem in the open ocean. They are major primary producers, major diazotrophs that fix dinitrogen …
Nutrient availability in tropical forests regulates important ecosystem processes and may also drive forests’ responses to global change. Textbooks often generalize tropical forests as nitrogen …
My dissertation broadly focused on understanding forest nutrient cycling and how disturbance and changing environmental conditions may alter this. I studied these dynamics through plant-microbe …
This dissertation investigates an old and fundamental question in evolutionary biology: how is adaptation maintained in highly heterogeneous environments? Adaptation in variable environments poses a …
This thesis investigates the intricate relationship between aerial predation, locomotion, and the unintended ecological consequences of human-made structures. Chapter one explores the predatory pursuit behavior …
The origin of air breathing required the evolution of a new structure (lungs) and a new behavior (surfacing, expiring, and inspiring), which posed the biomechanical …
I investigated factors that influence microbial diversity and composition and the consequences of this diversity for plant communities. First, I used cloning and sequencing of …
Domestic species are an example of experimental evolution involving intentional selective breeding for particular traits. These species provide an opportunity to study varying rates of …
Plant invasions are increasing worldwide and it is now commonplace to see coexistence between native and exotic species in many communities. As invasions are thought …
Animals of all kinds use gesture, or body movement, to communicate. Despite its ubiquity, this signaling mechanism is little studied on a functional or evolutionary …
Abstract of “Communities Within a Community: The Gut Microbiomes of Co-occurring Small Mammals in a Kenyan Savanna” by Bianca R. Palmer Brown, Ph.D., Brown University, …
Over the last decade novel methods in molecular biology have allowed greater access to the structure, composition and diversity of microbial communities across an increasingly …
In fish, the task of eating in an aquatic medium has resulted in a diversity of complex feeding mechanisms. My dissertation work investigated a selection …
Knowledge of genetic diversity within natural populations, how this variation is maintained, and its underlying selective drivers are central to both evolutionary ecology and biological …
Abstract of Development and Evolution of Scyphomedusae, by Rebecca R. Helm, Ph.D., Brown University, May 2016. Scyphozoan jellyfish are important members of marine ecosystems. Jellyfish, …
Dryland ecosystems were considered the most diverse in the Hawaiian archipelago. Today, less than 5% of original dryland habitat remains. Although contemporary wildfires and the …
Oceans cover 70% of the Earth's surface and each liter of seawater contains billions of microbes. These microbes account for most of the biomass in …
Tropical forests are important for provision of ecosystem services, meanwhile deforestation rates are high in the tropics to create pasture and agricultural lands. Regrowth of …
The fate of nitrate (NO3-) in marine sediments depends on a balance of microbially mediated processes that remove or recycle available nitrogen (N), i.e. denitrification …
The derived didactyl limbs of most extant artiodactyls have traditionally been viewed as adaptations for fast locomotion. The most primitive condition for artiodactyls is a …