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Habitat selection theory predicts that consumers should distribute themselves across alternative resources in a fitnessmaximizing manner. One such distribution is the ideal free distribution, where consumer density matches local resource density. Alternatively, if wing wear is an important cost of wing use for bees, there should be relatively more bee consumers in high density patches, resulting in “overmatching”. If the energetic costs of flight influence patch choice, there also should be relatively more consumers in high density patches (where flight costs are lower), resulting in “overmatching”. To examine these hypotheses, I observed the visitation of bumble bees (genus Bombus) across experimental manipulations of plant density in patches of bergamot (Monarda fistulosa) in southwest Alberta, Canada over 2 summers. Bees flew more often and for a greater proportion of time, and hit their wings more frequently, in low-density patches. In 2004, bees “undermatched” resources (relatively few bees...

Sexual spores (i.e., basidiospores) of the spruce cone rust (Chrysomyxa pirolata; Uredinales) produced on leaves of a small perennial herb, the common pink wintergreen (Pyrola asarifolia; Pyrolaceae), must travel from the forest floor to the forest canopy, where they infect the female cones of white spruce (Picea glauca; Pinaceae). Asexual spores (i.e., urediniospores) must move among pyrola plants on the forest floor. Spore transmission is complicated by relatively calm wind conditions within the forest, and the short critical period during which the cones of white spruce can be infected. Here, we document a correlation between the orientation of leaves in the pyrola and presence of rust pustules on the leaf’s ventral surface. We experimentally address the consequences to spore dispersal of this change in leaf position and presence of pustules. Transmission of rust spores can increase with higher leaf angles in two ways: (i) by raising the pustules further above the ground surface, thereby increa...