Meeting Abstract
Male hawkmoths, Manduca sexta, locate females for mating by tracking wind-borne plumes of female pheromone in flight. The quantity and quality of the odor and the timing of odor encounters are extracted from their environment using input from sensory cells on their antennae. Steering and navigation control are thought to depend on: 1) instantaneous spatial comparison between the two antennae, spatial sampling, or 2) comparison of odor inputs between two sequential sampling points, temporal sampling. If spatial sampling is important for plume tracking, removal of one antenna should diminish their ability to locate an odor source. However, removing one antenna should have less of an impact on temporal trackers, as they could still compare odor cues over time. To characterize the effects of different environments on plume tracking, we challenged males with only one odor-detecting antenna to track a plume in an either turbulent or laminar air flow. More than 50% of moths with only one odor-detecting antenna located the source in turbulent flow, dropping to ca. 30% in smooth air flow. Plumes are wider in turbulent flow and narrower in smooth flow. Males in treatment groups that had difficulty successfully locating the source also showed difficulty hovering. When a donor antenna was attached to the stump of the removed antenna prior to flight “re-loading” the large mechanoreceptors at the base flight stability, hovering and source location was partially recovered, more so in the turbulent flow environment. Bilateral mechanosensory input was more important for successful source location than bilateral odor information. We thank Jen Milligan, Kim Thompson and Sean Copley for their assistance. AES and MAW were supported by NSF grant IOS-1121498 and AFOSR grant FA9550-14-03987.
