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How we interact with our environment largely depends on both the external cues presented by our surroundings and the internal state from within. Internal states are the ever-changing physiological conditions that communicate the immediate survival needs and motivate the animal to behaviorally fulfill them. Satiety level constitutes such a state, and therefore has a dynamic influence on the output behaviors of an animal. In predatory insects like the praying mantis, hunting tactics, grooming, and mating have been shown to change hierarchical organization of behaviors depending on satiety. Here, we analyze behavior sequences of freely hunting praying mantises ( Tenodera sinensis ) to explore potential differences in sequential patterning of behavior as a correlate of satiety. First, our data supports previous work that showed starved praying mantises were not just more often attentive to prey, but also more often attentive to further prey. This was indicated by the increased time fraction spent in attentive bouts such as prey monitoring, head turns (to track prey), translations (closing the distance to the prey), and more strike attempts. With increasing satiety, praying mantises showed reduced time in these behaviors and exhibited them primarily towards close-proximity prey. Furthermore, our data demonstrates that during states of starvation, the praying mantis exhibits a stereotyped pattern of behavior that is highly motivated by prey capture. As satiety increased, the sequenced behaviors became more variable, indicating a shift away from the necessity of prey capture to more fluid presentations of behavior assembly. 

It is imperative that an animal have the ability to track its own motion within its immediate surroundings. It gives the necessary basis for decision making that leads to appropriate behavioral responses. It is our goal to implement insect-like body tracking capabilities into a robotic controller and have this serve as the first step toward adaptive robotic behavior. In an attempt to tackle the first step of body tracking without GPS or other external information, we have turned to arthropod neurophysiology as inspiration. The insect brain structure called the central complex (CX) is thought to be vital for sensory integration and body position tracking. The mechanisms behind sensory integration are immensely complex, but it was found to be done with an elegant neuronal architecture. Based on this architecture, we assembled a dynamical neural model of the functional core of the central complex, two structures called the protocerebral bridge and the ellipsoid body, in a simulation environment. Using non-spiking neuronal dynamics, our simulation was able to recreate in vivo behavior such as correlating body rotation direction and speed to activity bump dynamics within the ellipsoid body of the central complex. This model serves as the first step towards using idiothetic cues to track body position and orientation determination, which is critical for homing after exploring new environments and other navigational tasks.