Though rarely experimentally tested, biotic interactions have long been hypothesized to limit low-elevation range boundaries of species. We tested the effects of herbivory on three alpine-restricted plant species by transplanting plants below (novel), at the edge (limit), or in the center (core) of

Experimental infections of Arabidopsis thaliana (Arabidopsis) with genomically charac- terized plant pathogens such as Pseudomonas syringae have facilitated the dissection of canonical eukaryotic defence pathways and parasite virulence factors. Plants are also attacked by herbivorous insects, and th

Pollinator exclusion bags for small herbaceous plants are much more convenient to apply and remove if their bottom edge is made in the form of a cloth tunnel loaded with sand to conform to the terrain. Damage and inadvertent selfing of flowers are minimized.

1. We revisited bumble bee survey data collected by Pyke in 1974 (Pyke, Ecology , 63 , 555–573, 1982) to evaluate seasonal changes in abundances of bumble bees and their floral resources, diel patterns of bumble bee activity, and elevation effects on plant and bumble bee phenology. 2. Bumble bee abu

1. The extent to which flower colour and other visual cues influence butterfly flower choice in the field is poorly understood, especially in comparison with choices by Hymenoptera. 2. Using a novel approach to studies of visitation behaviour by butterflies, flower colour of four Asteraceae species

Abstract Song repertoire size is the number of distinct syllables, phrases, or song types produced by an individual or population. Repertoire size estimation is particularly difficult for species that produce highly variable songs and those that produce many song types. Estimating repertoire size is

higher densities in streams with the highest risk of vertebrate predation. Along with many students and other colleagues, we have spent many years trying to understand that perplexing pattern. Adaptive behavior and life history strategies that can be induced experimentally by predator risk result in

If related species share enemies, variation in the damage experienced by species within a community may be predictable based on phylogeny. We examined the hypothesis that plant species more closely related to other community members experience greater herbivory by assessing leaf damage to native and

Ralph E Clark. Western State College of Colorado. 2000.

Vicki Shaw. High Country Citizen’s Alliance. 2000.

James Amos. The Pueblo Chieftain. June 9, 2000.

Pamela Spath. National Renewable Energy Laboratory. September 2000.