Evolution of Insect Olfaction

Abstract

Neuroethology utilizes a wide range of multidisciplinary approaches to decipher neural correlates of natural behaviors associated with an animal's ecological niche. By placing emphasis on comparative analyses of adaptive and evolutionary trends across species, a neuroethological perspective is uniquely suited to uncovering general organizational and biological principles that shape the function and anatomy of the nervous system. In this review, we focus on the application of neuroethological principles in the study of insect olfaction and discuss how ecological environment and other selective pressures influence the development of insect olfactory neurobiology, not only informing our understanding of olfactory evolution but also providing broader insights into sensory processing.

Biomechanics of the stick insect antenna: Damping properties and structural correlates of the cuticle

“…Antennae are leglike appendages that have evolved to become dedicated sensory organs, combining various sensory modalities such as sound, gravi-, thermo-chemo-and in some cases probably even magnetoreception (Ferreira de Oliveira et al, 2010;Göpfert and Robert, 2001;Hansson, 1999;Sandeman, 1976;Tichy, 2007). They also mediate different mechanosensory cues provide tactile of versatility with simplicity makes an insect antenna not only a fascinating biological sense organ; it makes it a model for artificial tactile systems that use only a single probe Hellbach et al, 2010) as an alternative to arrays of hair-like whiskers (Kim and Möller, 2007;Pearson et al, 2007;Solomon and Hartmann, 2006).…”

Development of site fidelity in the nocturnal amblypygid, Phrynus marginemaculatus

“…It is important to note that the odor source was not used to test a hypothesis of olfactory navigation. There is good evidence that odors are used to assist navigation (Hansson and Stensmyr 2011;Jacobs 2012;Svensson et al 2014), so we included the odor source to increase environmental heterogeneity and facilitate the spatial discrimination of the two shelters. We monitored activity and space use over a session of five nights with an automated, real-time video tracker that continually recorded the coordinates of a subject when it was outside of a shelter.…”

“…As noted above, in this experiment, we provided an olfactory cue near the HS in the form of geraniol to enhance the spatial heterogeneity of the experimental environment and promote shelter discrimination but not to test whether the odor was used for homing (although it was likely it would be). Geraniol is a component of many plant-based essential oils and was chosen as an odor source because it is detected by numerous terrestrial arthropods (Hansson and Stensmyr 2011;Leonard and Masek 2014). Because amblypygids do not rely directly on plants as a food source, we hypothesized that geraniol would be neither a particularly attractive nor aversive stimulus.…”

Ca2+ imaging of cricket protocerebrum responses to air current stimulation

“…In the insect nervous system, visual input from the compound eye is primarily encoded by neural circuits of the optic lobe [4,35], and chemical signals sensed by antennae are conveyed to the antennal lobe, which is the primary olfactory center of insect brains [6,16]. In contrast, primary sensory circuits for input provided by thoracic and abdominal sensory organs are located within the lower ganglia.…”