Climate change is expected to alter patterns of species co-occurrence, in both space and time. Species-specific shifts in reproductive phenology may alter the assemblages of plant species in flower at any given time during the growing season. Temporal overlap in the flowering periods (co-flowering)

Status badges, such as bird plumage colors, are important parts of animal communication; they mediate intra- as well as intersexual interactions. Reliability of avian plumage badges is thought to be maintained by selective pressures, including social punishment. Costs, benefits, and resultant fitnes

Repeat photography is a field method to study landscape change over time, yet most studies use a single pair of photographs spanning upwards of a century or more to ascertain change. In this study, I used repeat photography to study vegetation change across high-elevation environments within the San

Non-native species and habitat degradation are two major catalysts of environmental change and often occur simultaneously. In freshwater systems, degradation of adjacent terrestrial vegetation may facilitate invasion by altering resource availability. Here we examine impacts of an invasive herbivoro

Terrestrial snow is an important freshwater reservoir with significant influence on the climate and energy balance. It exhibits natural spatiotemporal variability which has been enhanced by climate change, thus it is important to monitor on a large scale. Active microwave, or radar remote sensing ha

The species-area relationship (SAR) is a widely used concept in ecology, yet there is much controversy over its form. It has traditionally been assumed either to have a simple universal power-law form, S = cAz, or to be idiosyncratic, varying from habitat to habitat, taxa to taxa, and spatial scale

The way in which plants respond evolutionarily to environmental change partially depends on the magnitude of variation present within populations. In an attempt to understand the evolutionary response of Androsace septentrionalis (Rock Jasime) to current and future climate change in the Elk mountain

The diatom Didymosphenia geminata has become an increasing concern for aquatic habitats. The algae has spread within its native environment and exhibit invasive characteristics, as well as invade ecosystems outside of its native range. D. geminata does not appear to affect the species richness of an

Nectar robbing can affect both male and female components of plant reproduction. To understand the mechanisms driving those plant-reproductive outcomes, I studied the effects of nectar robbing on pollen deposition and pollinator behavior in the hummingbird-pollinated host plant Ipomopsis aggregata.

Previous studies by Pyke et al. have shown that bumblebees exhibit behavior that is consistent with optimal foraging theory. In this most recent effort, bumblebees were observed foraging on vertical inflorescences and their behavior was compared to a predicted model that would result in a maximum ne

At the Rocky Mountain Biological Laboratory (RMBL), revegetation is an important area of research because there are many areas of disturbed land that are more vulnerable to the spread of invasive species. In my project, I revisited a former student’s revegetation work in order to determine the long-

Song repertoire size is the range of distinct syllables, phrases, and song types created by an individual or population. Variations within songs create complex repertoires, making them difficult to estimate. There are several methods to estimate repertoire size, however prior studies discovered that

Mutualisms are commonly dependent on the ecological context in which partners interact. In ant‐aphid interactions, the dietary status of ants has been hypothesized to be one factor that may mediate ant‐aphid interactions. This hypothesis was supported in one laboratory study with one ant species. We

The carbon balance of a system is particularly sensitive to water availability because carbon availability drives both the mechanisms of photosynthesis and decomposition (Huxman et al. 2004 b, Ignace et al. 2007). The carbon balance of terrestrial plants is mainly a function of (i) carbon fixation t

Anthropogenic environmental change currently threatens to alter resource availability across the planet, likely driving responses by plant species. In the Colorado Rocky Mountains, climate change is expected to decrease soil moisture availability and increased nitrogen deposition is expected to incr

In flowering plants, environment-mediated hybrid fitness plays a large role in hybrid zone dynamics. The relationship of physiological traits to hybrid fitness, however, has not been described for many plant systems. In this study, we investigated the effects of soil moisture on water-use efficiency

Much of global biodiversity is comprised of parasitic organisisms. It is well recognized that the selective pressures imposed by parasites shape host defenses and life-history strategies. Many studies suggest that human changes to the environment facilitate pathogen emergence by disrupting establish

Optimal foraging theory states that there are benefits and costs from foraging. If the animal shows optimal foraging behavior, the benefits minus the costs from foraging should be maximized. One assumption of optimal foraging theory is that animals can recognize food, which for butterflies means det

The conservation of keystone species and their associates is of great importance due to the disproportionately large role they play in community and ecosystem structure. The Red-naped Sapsucker (Sphyrapicus nuchalis) is considered part of an intricate keystone species complex in the aspen forests of

Concerns of the decline of pollinators and their services have recently been raised. While several hypothesis have been studied, such has the shift of flowering phenology so it no longer overlaps with pollinators and habitat fragmentation, this study investigated the decline of the nectar robbing bu