Multimodal integration across spatiotemporal scales to guide invertebrate locomotion

Plant behavior: Theoretical and technological advances

The widespread disregard for plant behavior is gradually being overcome through more inclusive theoretical approaches and the development of appropriate and advanced technologies. In this paper we review scientific evidence on recent contributions to the study of plants, such as movement and communication as well as potential forms of attention. Some of the most recent contributions to the study of plant abilities come from comparative studies on biocommunication and research on the accuracy of plants in responding to different environmental stimuli through electrophysiological and kinematical analyses in different context (e.g., individual and social). Furthermore, an underexplored area that warrants further investigation is plants' multisensory perception and its potential link to multimodal communication capabilities. Research into this set of abilities could help to clarify the degree of behavioral flexibility in sessile organisms without a nervous system and enhance discussions on interactive behavior as expressed in nature. This, in turn, will help to bridge the gap between studies on animal organisms and the rest of the living world.

Chronic carbendazim exposure disrupts behavioral responses and redox-regulatory mechanisms in non-target detritivore Nauphoeta cinerea nymphs

Carbendazim is widely applied in agriculture to control various fungal diseases during pre-harvest and post-harvest processes owing to its efficacy and cost-effectiveness. However, environmental and food contamination by carbendazim has become a global health issue. Indeed, the declining biodiversity of beneficial insects owing to agricultural intensification is currently of keen concern to the scientific community. The toxicological responses of Nauphoeta cinerea nymphs, a non-target insect, to ecologically realistic concentrations of carbendazim at 0, 0.25, 2.5, 5.0 and 25 μg/L for 50 uninterrupted days were assessed. Neurobehavioral data generated by video-tracking software revealed that chronic nymphal exposure to carbendazim significantly diminished the path efficiency, body rotation, maximum speed, turn angle and distance traveled but increased the immobility time, total time of freezing and episodes of freezing in insects. The deterioration in the locomotor and exploratory abilities of carbendazim-exposed insects was substantiated by high heat map intensity and reduced track plots. Further, chronic carbendazim exposure diminished acetylcholinesterase activity in head of the insects. Chronic carbendazim exposure significantly decreased antioxidant defense mechanisms but increased nitric oxide, hydrogen peroxide and lipid peroxidation levels in fat body, midgut and head of exposed insects. Activities of acid and alkaline phosphatases which play important roles in detoxification and metabolic processes were also markedly decreased in carbendazim-exposed insects when compared with control. Altogether, carbendazim represents an ecological threat to non-target insects through induction of oxido-inflammatory injury, providing valuable insights into the behavioral dysfunction and toxicological mechanisms of carbendazim in beneficial insects.

Moving in an Uncertain World: Robust and Adaptive Control of Locomotion from Organisms to Machine Intelligence

Whether walking, running, slithering, or flying, organisms display a remarkable ability to move through complex and uncertain environments. In particular, animals have evolved to cope with a host of uncertainties-both of internal and external origin-to maintain adequate performance in an ever-changing world. In this review, we present mathematical methods in engineering to highlight emerging principles of robust and adaptive control of organismal locomotion. Specifically, by drawing on the mathematical framework of control theory, we decompose the robust and adaptive hierarchical structure of locomotor control. We show how this decomposition along the robust-adaptive axis provides testable hypotheses to classify behavioral outcomes to perturbations. With a focus on studies in non-human animals, we contextualize recent findings along the robust-adaptive axis by emphasizing two broad classes of behaviors: (1) compensation to appendage loss and (2) image stabilization and fixation. Next, we attempt to map robust and adaptive control of locomotion across some animal groups and existing bio-inspired robots. Finally, we highlight exciting future directions and interdisciplinary collaborations that are needed to unravel principles of robust and adaptive locomotion.

Experience with Aposematic Defense Triggers Attack Bias in a Mantid Predator (Stagmomantis carolina)

Studies of predator psychology in aposematism have suggested important effects of signal detection through space and time on outcomes of attack behavior. Both the integration of aposematic signals from prey and experience state of the predator can have important effects on attack decisions. The universality of these effects however, especially as it applies to non-avian predators such as arthropods, remains poorly understood. We examined the effects of multimodal aposematic signaling and prior experience with aposematism on attack latency and attack likelihood of the Carolina mantis (Stagmomantis carolina). Using artificial prey bearing visual and olfactory signals of the convergent lady beetle (Hippodamia convergens), we tested 2 cohorts of mantids (representing juvenile and adult stages) across 4 groups: visual only, odor only, combined signals, and control. We then used approaches in linear modeling to test the hypotheses that (1) prior experience with aposematism alters attack behavior toward aposematic prey and (2) multimodal signals have synergistic effects on attack behavior relative to either unisensory signal presented alone. We found support for the first hypothesis in that mantids employ attack biases against visual and olfactory aposematic signals, but only after prior exposure to aposematism and only as juveniles. While support is lacking for multimodal integration by the mantids, this study is the first to suggest a response of mantids to an aposematic olfactory signal (in addition to visual signal) and may suggest a developmental window for mantid predators to develop biases toward aposematic prey that are shaped by experience.

Drosophila flying in augmented reality reveals the vision-based control autonomy of the optomotor response

For walking, swimming, and flying animals, the optomotor response is essential to stabilize gaze. How flexible is the optomotor response? Classic work in Drosophila has argued that flies adapt flight control under augmented visual feedback conditions during goal-directed bar fixation. However, whether the lower-level, reflexive optomotor response can similarly adapt to augmented visual feedback (partially autonomous) or not (autonomous) over long timescales is poorly understood. To address this question, we developed an augmented reality paradigm to study the vision-based control autonomy of the yaw optomotor response of flying fruit flies (Drosophila). Flies were placed in a flight simulator, which permitted free body rotation about the yaw axis. By feeding back body movements in real time to a visual display, we augmented and inverted visual feedback. Thus, this experimental paradigm caused a constant visual error between expected and actual visual feedback to study potential adaptive visuomotor control. By combining experiments with control theory, we demonstrate that the optomotor response is autonomous during augmented reality flight bouts of up to 30 min, which exceeds the reported learning epoch during bar fixation. Agreement between predictions from linear systems theory and experimental data supports the notion that the optomotor response is approximately linear and time invariant within our experimental assay. Even under positive visual feedback, which revealed the stability limit of flies in augmented reality, the optomotor response was autonomous. Our results support a hierarchical motor control architecture in flies with fast and autonomous reflexes at the bottom and more flexible behavior at higher levels.

Linking neural circuits to the mechanics of animal behavior in Drosophila larval locomotion

The motions that make up animal behavior arise from the interplay between neural circuits and the mechanical parts of the body. Therefore, in order to comprehend the operational mechanisms governing behavior, it is essential to examine not only the underlying neural network but also the mechanical characteristics of the animal's body. The locomotor system of fly larvae serves as an ideal model for pursuing this integrative approach. By virtue of diverse investigation methods encompassing connectomics analysis and quantification of locomotion kinematics, research on larval locomotion has shed light on the underlying mechanisms of animal behavior. These studies have elucidated the roles of interneurons in coordinating muscle activities within and between segments, as well as the neural circuits responsible for exploration. This review aims to provide an overview of recent research on the neuromechanics of animal locomotion in fly larvae. We also briefly review interspecific diversity in fly larval locomotion and explore the latest advancements in soft robots inspired by larval locomotion. The integrative analysis of animal behavior using fly larvae could establish a practical framework for scrutinizing the behavior of other animal species.

Polarization sensitivity and decentralized visual processing in an animal with a distributed visual system

The marine mollusc Acanthopleura granulata (Mollusca; Polyplacophora) has a distributed visual array composed of hundreds of small image-forming eyes embedded within its eight dorsal shell plates. As in other animals with distributed visual systems, we still have a poor understanding of the visual capabilities of A. granulata and we have yet to learn where and how it processes visual information. Using behavioral trials involving isoluminant looming visual stimuli, we found that A. granulata demonstrates spatial vision with an angular resolution of 6 deg. We also found that A. granulata responds to looming stimuli defined by contrasting angles of linear polarization. To learn where and how A. granulata processes visual information, we traced optic nerves using fluorescent lipophilic dyes. We found that the optic nerves innervate the underlying lateral neuropil, a neural tissue layer that circumnavigates the body. Adjacent optic nerves innervate the lateral neuropil with highly overlapping arborizations, suggesting it is the site of an integrated visuotopic map. Using immunohistochemistry, we found that the lateral neuropil of A. granulata is subdivided into two separate layers. In comparison, we found that a chiton with eyespots (Chiton tuberculatus) and two eyeless chitons (Ischnochiton papillosus and Chaetopleura apiculata) have lateral neuropil that is a singular circular layer without subdivision, findings consistent with previous work on chiton neuroanatomy. Overall, our results suggest that A. granulata effectuates its visually mediated behaviors using a unique processing scheme: it extracts spatial and polarization information using a distributed visual system, and then integrates and processes that information using decentralized neural circuits.

Cross-modal facilitation of auditory discrimination in a frog

Stimulation in one sensory modality can affect perception in a separate modality, resulting in diverse effects including illusions in humans. This can also result in cross-modal facilitation, a process where sensory performance in one modality is improved by stimulation in another modality. For instance, a simple sound can improve performance in a visual task in both humans and cats. However, the range of contexts and underlying mechanisms that evoke such facilitation effects remain poorly understood. Here, we demonstrated cross-modal stimulation in wild-caught túngara frogs, a species with well-studied acoustic preferences in females. We first identified that a combined visual and seismic cue (vocal sac movement and water ripple) was behaviourally relevant for females choosing between two courtship calls in a phonotaxis assay. We then found that this combined cross-modal stimulus rescued a species-typical acoustic preference in the presence of background noise that otherwise abolished the preference. These results highlight how cross-modal stimulation can prime attention in receivers to improve performance during decision-making. With this, we provide the foundation for future work uncovering the processes and conditions that promote cross-modal facilitation effects.

Construction of Swimmer's Underwater Posture Training Model Based on Multimodal Neural Network Model

Swimming monitoring based on acceleration sensor is an emerging research direction in the field of human motion recognition. As a public sport, swimming has a wide audience. The swimming monitoring system can facilitate people to monitor and record their own swimming data, so as to formulate a reasonable training plan. Aiming at the defects of single modal information representation ability, high contingency, and easy to be influenced by the outside world, this paper adopts the underwater posture training model of swimmers to perform multimodal information fusion. In this paper, a multimodal information fusion method based on evolutionary neural network is proposed, and an intelligent perception information processing model of the intelligent subject system is constructed. Aiming at the defect that the accuracy and speed of the underwater posture monitoring of swimmers cannot be guaranteed in a complex environment, an evolutionary neural network optimized by a multimodal adaptive genetic algorithm is constructed to perform multimodal information fusion to ensure the effectiveness of the system in the face of complex information. Regarding attitude detection, it mainly uses the three dimensions of the angle of movement, the influence of gravity, and the strength and speed of the movement to measure. The MPU6050 module processor has a wide range of applications and is a mold processing tool with high performance and level. It completes the data processing, data calculation, and data storage of the inspection system in this paper. This paper further studies the working principle, structure, and operation process of this module and adjusts the time error in the detection of carrier motion and attitude so that the processing function of this module can play an optimal state. Four kinds of swimming posture measurement experiments were carried out on the swimmers, and the experimental data were analyzed. The whole system is controlled by the host computer man-machine interaction software remotely and in real time through commands. The experimental results show that the system realizes the detection of the basic posture, meets the basic requirements of the system design, and provides a certain foundation for the follow-up research.

Spatio-Temporal Dynamics in Animal Communication: A Special Issue Arising from a Unique Workshop-Symposium Model

Investigating how animals navigate space and time is key to understanding communication. Small differences in spatial positioning or timing can mean the difference between a message received and a missed connection. However, these spatio-temporal dynamics are often overlooked or are subject to simplifying assumptions in investigations of animal signaling. This special issue addresses this significant knowledge gap by integrating work from researchers with disciplinary backgrounds in neuroscience, cognitive ecology, sensory ecology, computer science, evolutionary biology, animal behavior, and philosophy. This introduction to the special issue outlines the novel questions and approaches that will advance our understanding of spatio-temporal dynamics of animal communication. We highlight papers that consider the evolution of spatiotemporal dynamics of behavior across sensory modalities and social contexts. We summarize contributions that address the neural and physiological mechanisms in senders and receivers that shape communication. We then turn to papers that introduce cutting edge technologies that will revolutionize our ability to track spatio-temporal dynamics of individuals during social encounters. The interdisciplinary collaborations that gave rise to these papers emerged in part from a novel workshop-symposium model, which we briefly summarize for those interested in fostering syntheses across disciplines.