Living organisms experience a worldwide continuous increase in artificial light at night (ALAN), negatively affecting their behaviour. The field cricket, an established model in physiology and behaviour, can provide insights into the effect of ALAN on insect behaviour. The stridulation and locomotion patterns of adult male crickets reared under different lifelong ALAN intensities were monitored simultaneously for five consecutive days in custom-made anechoic chambers. Daily activity periods and acrophases were compared between the experimental groups. Control crickets exhibited a robust rhythm, stridulating at night and demonstrating locomotor activity during the day. By contrast, ALAN affected both the relative level and timing of the crickets' nocturnal and diurnal activity. ALAN induced free-running patterns, manifested in significant changes in the median and variance of the activity periods, and even arrhythmic behaviour. The magnitude of disruption was light intensity dependent, revealing an increase in the difference between the activity periods calculated for stridulation and locomotion in the same individual. This finding may indicate the existence of two peripheral clocks. Our results demonstrate that ecologically relevant ALAN intensities affect crickets’ behavioural patterns, and may lead to decoupling of locomotion and stridulation behaviours at the individual level, and to loss of synchronization at the population level.

A major challenge in designing technologies that are intended to work in direct contact with humans lies in achieving maximal coordination between the human and the technological device (robot), while minimizing interference with or restraint of the normal human behavior. This is particularly relevant to systems designed to assist in human walking. Our current study presents an innovative bio-inspired approach to ensure a robust and consistent coupling between a human and a four-legged walking-device, to assist in walking-related challenges. These can be, for example, cases of limited stability during walking (due to old age, or any walking-related pathology), a need for excessive loadcarrying while walking, and more. We utilize ample previous knowledge of six-legged (insect) locomotion, its major advantages and related mechanisms, together with recent advances in monitoring human walking gait. We present a detailed computer simulation of the coordinated motion of a four-legged robotic device, tightly coupled to the movement of a walking human (a coupled human-robotic six-legged walking system). The simulated technology ensures at all times a consistent, stable, and efficient coupled walking gait. The robotic device maintains the coupling both during normal walking and during perturbations such as induced by a challenging terrain or simply by human instability. Preliminary tests of the technology using a physical model have demonstrated the system's ability to operate in the real world. Most importantly, in all instances, the device and the technology developed are totally transparent to the user, in the sense that they require no dedicated change or adjustment of the human's on-going walking behavior.