The increase in corolla length provides a rare example of a match between predicted and observed evolution of a plant trait in natural populations. The clinal properties are consistent with the hypothesis that habitat-mediated divergent selection on vegetative traits and pollinator-mediated selectio

AbstractMost herbivorous insect species are restricted to a narrow taxonomic range of host plant species. Herbivore species that feed on mustard plants and their relatives in the Brassicales have evolved highly efficient detoxification mechanisms that actually prevent toxic mustard oils from forming

This chapter contains sections titled: Introduction Background Geometric and Kinematic Analysis of the Black Canyon Region The Dubois and Cochetopa Successions The Black Canyon and Dubois Succession Contact The Cebolla Creek Quartzite Conglomerate The Proterrozoic Rocks of the Uncompahgre Plateau U-

Abstract. Soil thickness plays a central role in the interactions between vegetation, soils, and topography, where it controls the retention and release of water, carbon, nitrogen, and metals. However, mapping soil thickness, here defined as the mobile regolith layer, at high spatial resolution rema

PremiseIndustrialization and human activities have elevated temperatures and caused novel precipitation patterns, altering soil moisture and nutrient availability. Predicting evolutionary responses to climate change requires information on the agents of selection that drive local adaptation and infl

The weathering of shale exerts an important control on the hydrochemical fluxes to river systems, thus influencing the global carbon, nutrient, and geochemical cycles. However, the quantitative understanding of shale weathering and its impact on global biogeochemical cycles remains inadequate due to

The ecology of quaking aspen was studied in Gunnison County, Colorado. In the study area, aspen stands often take the form of small islands surrounded by fescue grasslands. At its upper altitudinal limits, aspen generally abuts the spruce-fir forest. The greatest number of trees were 4- to 7-in DBH

AbstractGenetic variation at the major histocompatibility complex (MHC) is vitally important for wildlife populations to respond to pathogen threats. As natural populations can fluctuate greatly in size, a key issue concerns how population cycles and bottlenecks that could reduce genetic diversity w

Blooms of the river benthic diatom Didymosphenia geminata are an enigma because they occur under phosphorus-poor conditions. A recent proposal that ferric–ferrous iron redox shifts sequester the additional phosphorus needed to stimulate and sustain D. geminata blooms does not agree with published ex

Looking at the entire flower community as a resource for foraging pollinators, it is found that flowers are an unreliable resource, especially in unpredictable environments.

Uncertainties in the calculation of water and phosphorus budgets for a bottom‐withdrawal reservoir were determined for 1979–1982. Ungaged components of the water budget were estimated from the residual of measured terms. This residual accounted for less than 30% of total water input and for more tha

Context The ability to identify priority habitat is critical for species of conservation concern. The designation of critical habitat under the US Endangered Species Act 1973 identifies areas occupied by the species that are important for conservation and may need special management or protection. H

Mountain big sagebrush (Artemisia tridentata Nutt. ssp. vaseyana) covers large areas in arid regions of western North America. Climate-change models predict a decrease in the range of sagebrush, but few studies have examined details of predicted changes on sagebrush growth and the potential impacts

It is found that, after over 100 years, these disturbed plant communities remained distinct from similar surrounding undisturbed areas, suggesting that biotic factors structure vegetation communities even hundreds of years following disturbance.

This study describes the stratigraphic characteristics and distribution of fluvial deposits of the Upper Cretaceous Williams Fork Formation in a portion of Rulison Field and addresses 3D geologic modelling of reservoir sand bodies and their associated connectivity. Fluvial deposits include isolated

ABSTRACT: The Gunnison River in the Gunnison Gorge is a canyon river where upstream dams regulate mainstem discharge but do not affect debris‐flow sediment supply from tributaries entering below the reservoirs. Regulation since 1966 has altered flood frequency, streambed mobility, and fluvial geomor

Secondary transfer of pollen can occur when a second pollinator remobilizes grains that had already been transferred to a flower by a previous pollinator. We used a pollen-color dimorphism to measure components of secondary transfer by bumble bees visiting the lily Erythronium grandiflorum. Remobili

Although reciprocity of affiliative exchanges within cohorts increased as individuals matured, competition among genetic relatives emerged early in ontogeny and persisted into adulthood, suggesting that close affiliates are each other's closest competitors.

Stable isotope ratios of precipitation are useful tracers of climatic and hydrological processes. To better understand the isotope hydro-climatology of a high-elevation Rocky Mountain valley we collected meteoric water samples from Gunnison, Colorado, USA and determined stable isotope values for 239