This is a map of variability in accumulated freezing potential (freezing degree days, FDD) for the Upper Gunnison domain, derived from daily minimum temperature maps interpolated from weather station and microclimate sensor data. The original daily maps are also available. Freezing degree-days were

This is a map of accumulated freezing potential (freezing degree days, FDD) for the Upper Gunnison domain, derived from daily minimum temperature maps interpolated from weather station and microclimate sensor data. The original daily maps are also available. Freezing degree-days were accumulated fro

It is shown that ants are a Limited and Limiting resource for a tended aphid species and that fireweed aphids compete with intra-and interspecific aphid neighbors for the services of ant mutualists.

The aim of this study was to determine the effects of circulating catecholamines and light on the daily melatonin rhythm in the marmot. Endogenous levels of circulating catecholamines and plasma melatonin were measured during arousal from hibernation in light and stuthes were performed on the circad

Seed set after selfing in E. grandiflorum is often reduced relative to seed set after crossing; however, the compatibility patterns seen are not due to genes of major effect (i.e., S alleles). There is quantitative variation in the proportion of pollen tubes reaching the base of the style after both

I measured phenotypic selection of floral traits through both male and female functions of the hermaphroditic flowers of Ipomopsis aggregata (Pursh) V. Grant subsp. aggregata (Polemoniaceae). Fluorescent powdered dyes were used to track movement of pollen by hummingbirds and to measure pollen delive

One explanation for low fruit sets in plants with hermaphroditic flowers is that total flower production by a plant is controlled primarily by selection through male function. This male function hypothesis presupposes that success in pollen donation increases more strongly with flower number than do

Gel electrophoresis was used to obtain an estimate of the genetic similarity among populations of Euphydryas anicia, Euphydryas chalcedona, and Euphydryas colon in an effort to determine whether they should be considered separate species or arbitrary groupings of populations in a single polytypic sp

Abstract Kin discrimination should be a tactic in the fitness strategy of individuals. Two postulates derived from inclusive fitness theory that fitness benefits toward kin are correlated with degree of relatedness and that social behavior of members of a kin group is always cooperative are refuted

Investigation of this mating system in Epeerus longimanus, a mayfly of the western United States that forms swarms that are quite large, finds that swarm locations are not explainable as feeding or emergence sites, but they do correlate with landscape features.

We determined the distance travelled by drifting nymphs of the mayflies Baetis and Cinygmula to add to existing knowledge of factors influencing drift distance, and to investigate the influence of drift-exiting behavior upon drift magnitude and periodicity. Individuals were released into the water c