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Pollination syndromes refer to stereotyped floral characteristics (flower colour, shape, etc.) that are associated with a functional group of pollinators (bee, bird, etc.). The trumpet creeper Campsis radicans, endemic to the southeast and mid‐west United States, has been assigned to the hummingbird‐pollination syndrome, due mainly to its red, trumpet‐shaped flowers. Previous studies demonstrated that the ruby‐throated hummingbird Archilochus colubris is C. radicans' primary pollinator, but anecdotal data suggest various bee species may provide pollination service when hummingbirds are absent. This study characterised C. radicans nectar volume and concentration by time of day. Nectar volume was suitable for hummingbirds, but concentration was higher than typical hummingbird‐pollinated plants (∼20% w/w); at ∼30% w/w, it approached the concentration expected in bee‐pollinated plants (∼50% w/w). We also found substantial amounts of nectar at night. Two C. radicans populations received virtually no hummingbird visits, but the number of bees were markedly higher than in the populations previously described. Interestingly, there were no night‐time visitors despite the large quantity of nocturnal nectar. Based on previously published pollen delivery per visit by various species, this study estimated that cumulative deposition by bees routinely reached pollen deposition thresholds for setting fruit in C. radicans. They are, unequivocally, the predominant pollinators in these populations, thus providing pollination service in the absence of hummingbirds. These results highlight C. radicans as a food source for native bees and add to the understanding of how floral phenotypes can facilitate pollination by disparate functional groups.

Fatty acid and stable isotope signatures allow researchers, managers, and policy makers to better understand food webs, food sources, and trophic relationships. Research in marine and lentic systems has indicated that the variance of these biomarkers can exhibit substantial differences across spatial and temporal scales, but this type of analysis has not been completed for large river systems. Our objectives were (a) to evaluate variance structures for fatty acids and stable isotopes (i.e., δ¹³C and δ¹⁵N) of seston, threeridge mussels, hydropsychid caddisflies, gizzard shad, and bluegills across spatial scales (10s–100s of km) in large rivers of the Upper Mississippi River Basin, USA, that were sampled annually for 2 years and (b) to evaluate the implications of this variance on the design and interpretation of trophic studies. The greatest variance for both stable isotopes was present at the largest spatial scale for all taxa (except seston δ¹⁵N), indicating that these isotopic signatures are responding to factors at a larger geographic level rather than being influenced by local‐scale alterations. Conversely, the greatest variance for fatty acids was present at the smallest spatial scale (i.e., among individuals) for all taxa except caddisflies, indicating that the physiological and metabolic processes that influence fatty acid profiles can differ substantially between individuals at a given site. Our results highlight the need to consider the spatial partitioning of variance during sample design and analysis, as some taxa may not be suitable for use in assessing ecological questions at larger spatial scales.

The mushroom bodies (MBs) are insect brain regions important for sensory integration, learning, and memory. In adult worker honey bees (Apis mellifera), the volume of neuropil associated with the MBs is larger in experienced foragers compared with hive bees and less experienced foragers. In addition, the characteristic synaptic structures of the calycal neuropils, the microglomeruli, are larger but present at lower density in 35-day-old foragers relative to 1-day-old workers. Age- and experience-based changes in plasticity of the MBs are assumed to support performance of challenging tasks, but the behavioral consequences of brain plasticity in insects are rarely examined. In this study, foragers were recruited from a field hive to a patch comprising two colors of otherwise identical artificial flowers. Flowers of one color contained a sucrose reward mimicking nectar; flowers of the second were empty. Task difficulty was adjusted by changing flower colors according to the principle of honey bee color vision space. Microglomerular volume and density in the lip (olfactory inputs) and collar (visual inputs) compartments of the MB calyces were analyzed using anti-synapsin I immunolabeling and laser scanning confocal microscopy. Foragers displayed significant variation in microglomerular volume and density, but no correlation was found between these synaptic attributes and foraging performance. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 77: 1057-1071, 2017.

This chapter describes a movement to significantly increase student attainment in community and technical colleges. The observations of Leadership Coaches in Achieving the Dream, developed over a nine-year period of involvement, provide insight into the leadership required to transform institutional culture.

How can one expect a consultant to accomplish something a president is unwilling or unable to do? The president should be the leader in organization development.

■"ПНЕ first requirement in organizing Jand operating a saf ty program for a w ter utility or sewer district is that the manager be completely sold on the progr m. With his backing and continuous support a suggested safety progra can be established. Without the help and continuous backing of the manager, the establishment of a safety program is practically impossible. The job of selling the manager n its benefits should not be too difficult if the utility's, the employees', and the public's share of the costs due to accidents are made clear to him. The costs