Manduca sexta is a model organism commonly used for physiological and behavioral studies. M.sexta are facultative specialists typically reared in captivity with an artificial diet consisting of wheat germ, yeast, and a variety of other vitamins while the typical diet of M.sexta includes mainly solanaceous plants. Stimulus acknowledgement is important for understanding the minimum force that an organism can perceive or react to. In previous studies, mechanoreception has shown to vary significantly among parasitized and unparasitized caterpillars. Furthermore, the diet of an organism is very important for its long term health and vitality, so this study set out to determine the differences in stimulus acknowledgement between M.sexta of different diets and parasitism status. It is hypothesized that plant-reared caterpillars will have a lower threshold to mechanoreception based on feeding off of a natural over an artificial diet. The stimulus acknowledgement, or twitch, threshold was tested for artificial diet-reared, plant-reared, and plant-reared parasitized caterpillars to determine if any significant correlations exist between the three groups. Using a linear mixed model, it was found that significant differences (p < .001) in stimulus acknowledgement exist between the three groups. Through post-hoc analyses of covariance (ANCOVA), significant differences (p < .001) between each instar among the three groups were also identified. These findings strengthen the hypothesis that feeding on a natural diet correlates with bodily systems developing optimally. Further study should explore the physiological and biochemical mechanisms by which C.congregata manipulate the host M.sexta by inducing higher mechanosensitivity in parasitized caterpillars.
.png)
