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The anthologist of The Golden Treasury, F. T. Palgrave, recorded a conversation with Tennyson in which the poet claimed 'his poems sprang from a 'nucleus', some one word, may be, [...]

David Collings contends that the conception of culture pervading Wordsworth's great poetry is based on a rejection of human relationship. Many of Wordsworth's errant solitaries lead lives that embody the [...]

The western tree hole mosquito, Aedes sierrensis (Ludlow) (Diptera: Clucidae), is a pestiferous mosquito with a range extending over the entire pacific seaboard and into portions of the intermountain west. As a peridomestic heartworm vector, it demands at least some level of surveillance to understand its abundance. However, the species is refractory to a majority of conventional vector surveillance approaches for tracking mosquitoes. To find more options for Aedes sierrensis surveillance, a variety of oviposition attractants were evaluated in arena-style choice assays using colony reared adults. A range of infusion treatments (e.g., alfalfa, oak, and beetroot) were examined and then combined with investigations of liquid color as well as ovicup color and entryway position. These studies revealed that Ae. sierrensis have an affinity for purple coloration, plain water, and larger entryway sizes for oviposition cups. A prototype ovicup was 3D-printed using purple filament and multiple types of entryways, and used to re-test infusion waters. No particular attraction differences were detected after normalizing for purple color. Comparisons to black 3D-printed cups yielded surprising observations that male mosquitoes also aggregated on purple cups while females sheltered, but not necessarily oviposited, in black cups. Although this was only a laboratory-based assessment, these studies provide useful information for future field trials of potential oviposition traps for surveillance of Ae. sierrensis., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

We used single-sensillum recordings to characterize male Heliothis subflexa antennal olfactory receptor neuron physiology in response to compounds related to their sex pheromone. The recordings were then followed by cobalt staining in order to trace the neurons' axons to their glomerular destinations in the antennal lobe. Receptor neurons responding to the major pheromone component, (Z)-11-hexadecenal, in the first type of sensillum, type-A, projected axons to the cumulus of the macroglomerular complex (MGC). In approximately 40% of the type-A sensilla, a colocalized receptor neuron was stained that projected consistently to the posterior complex 1 (PCx1), a specific glomerulus in an 8-glomerulus complex that we call the Posterior Complex (PCx). We found that receptor neurons residing in type-B sensilla and responding to a secondary pheromone component, (Z)-9-hexadecenal, send their axons to the dorsal medial glomerulus of the MGC. As in the type-A sensilla, we found a cocompartmentalized neuron within type-B sensilla that sends its axon to a different glomerulus of the PCx4. One neuron in type-C sensilla tuned to a third pheromone component, (Z)-11-hexadecenol, and a colocalized neuron responding to (Z)-11-hexadecenyl acetate projected their axons to the anteromedial and ventromedial glomeruli of the MGC, respectively.

Terrestrial odor plumes have a physical structure that results from turbulence in the fluid environment. The rapidity of insect flight maneuvers within a plume indicates that their responses are dictated by fleeting (<1 s) rather than longer (>1 s) exposures to odor imposed by physical variables that distribute odor molecules in time and space. Even though encounters with pheromone filaments are brief, male moths responding to female-produced pheromones are remarkably able to extract information relating to the biological properties of these olfactory signals. These properties include the types of molecule present and their relative abundances. Thus, peripheral and central olfactory neurons are capable of representing these biological properties of a pheromone plume within the context of a temporally irregular and unpredictable signal. The mechanisms underlying olfactory processing of these signals with respect to their biological and physical properties are discussed in the context of a behavioral framework.

In different moth species, the number and spatial arrangement of olfactory glomeruli in the antennal lobe (AL) vary widely, but the spatial map within a species is thought to be invariant, making it possible to identify single glomeruli across individuals. We investigated the relationship between the physiological tuning of pheromone-selective interneurons and their association with specific, identified glomeruli in the macroglomerular complex (MGC) of the noctuid moth, Heliothis subflexa. Three odorants that are required for pheromone-source location in this species were tested individually and in blends. Recordings from 27 pheromone-specific projection neurons (PNs) indicated that the majority (48%) were selectively activated by the major pheromone component of this species, Z-11-hexadecenal (Z11-16:Ald), with 33% primarily tuned to Z-9-hexadecenal and 19% to Z-11-hexadecenol. Intracellular staining revealed that the dendrites of PNs tuned to Z11-16:Ald always branched within the largest glomerulus of the MGC, the cumulus. Similarly, each of the other two classes of PN was associated with a different 'satellite' glomerulus in the MGC. The spatial configuration of the four-glomerulus H. subflexa MGC was indistinguishable from that previously reported in the closely related species, Heliothis virescens. Hence, as these two species diverged, changes in the association of satellite MGC glomeruli with particular odorants have occurred without a measurable change in the anatomical arrangement of the glomerular array.