Biology subjects

Shigaki, S.

Publications and source records attributed to Shigaki, S..

3 recordsLinked to original sources

bioRxiv2024

Odor source localization behavior of an insect enhanced by intermittent intake strategy

This study investigated odor acquisition strategies to enhance odor plume tracking performance. Efficient odor plume tracking is a crucial ability for organisms, affecting their survival, including for insects with relatively simple nervous systems. Insects can use odor cues to locate food sources or potential mates. Odors released from a source disperse in complex patterns owing to air currents and collisions with objects, making their spread unpredictable. Organisms must therefore engage in active odor acquisition behaviors to effectively gather spatial information from this highly uncertain odor environment. This study focused on odor acquisition via wing flapping in a male silk moth and its relationship with female localization. Given the difficulty of directly intervening in wing flapping, we employed an insect-mounted robotic system to engineer interventions and investigate the relationship between wing-flapping-induced odor acquisition and localization. We found that the difference between air inflow and stoppage in odor attraction was large, and that the odor plume tracking performance was highest at 10 Hz, where odor attraction can be performed at high frequencies. Although constant strong odor acquisition improves localization performance, it increases the likelihood of movement in directions other than that of the odor source. This suggests that periodic wing flapping helps to suppress undesired movements.

animal behavior and cognition↗

bioRxiv2024

Sexually dimorphic auditory representation in Aedes aegypti brains

Male attraction to female flight sounds is a vital, reproducible component of courtship in many species of mosquitoes; however, female acoustic behaviours have proven challenging to define. To investigate sexual dimorphisms in acoustic behaviours, previous reports have largely focused on differences in mosquito peripheral ear anatomy and function. Whilst molecular investigations have recently begun on the auditory periphery, sexual dimorphisms in central processing of acoustic information have not yet been explored. Here we used a combination of neurotracing, calcium imaging and molecular analyses to examine sexual dimorphisms in auditory processing in the yellow fever mosquito Aedes aegypti. We identified shared and dimorphic neurons connecting male and female ears to the primary auditory processing centre in the brain, and defined multiple distinct neuronal clusters based on responses to auditory stimulation. We finally used transcriptomic and proteomic analyses to investigate the molecular factors underlying these differences, with motile ciliary-related terms significantly enriched in males.

neuroscience↗

bioRxiv2021

Analysis of Multisensory-Motor Integration in Olfactory Navigation of Silkmoth, Bombyx mori, using Virtual Reality System

Most animals survive and thrive due to navigation behavior to reach their destinations. In order to navigate, it is important for animals to integrate information obtained from multisensory inputs and use that information to modulate their behavior. In this study, by using a virtual reality (VR) system for an insect, we investigated how an adult silkmoth integrates visual and wind direction information during female search behavior (olfactory behavior). According to the behavioral experiments using the VR system, the silkmoth had the highest navigation success rate when odor, vision, and wind information were correctly provided. However, we found that the success rate of the search significantly reduced if wind direction information was provided that was incorrect from the direction actually detected. This indicates that it is important to acquire not only odor information, but also wind direction information correctly. In other words, Behavior was modulated by the degree of co-incidence between the direction of arrival of the odor and the direction of arrival of the wind, and posture control (angular velocity control) was modulated by visual information. We mathematically modeled the modulation of behavior using multisensory information and evaluated it by simulation. As a result, the mathematical model not only succeeded in reproducing the actual female search behavior of the silkmoth, but can also improve search success relative to the conventional odor source search algorithm.

systems biology↗