Meeting Abstract
Desert kangaroo rats (Dipodomys deserti) exhibit highly successful escape maneuvers when subject to a predatory attack. Prior studies have loosely attributed the species’ success to the unpredictable nature of their evasive response, yet the exact mechanisms remain unknown. Based on literature emphasizing the role of auditory sensitivity in predator-prey dynamics, our goal was to compare kangaroo rat reaction times between auditory and visual cues in the field. For analysis, we used high-speed video cameras (240 fps) to record locomotor response prompted by a rattlesnake strike simulator (RSS). Although the RSS was originally developed to investigate overall escape kinematics, this analysis focused solely on reaction time. Our modified RSS included both auditory and visual triggers, deploying at staggered intervals. For auditory stimulus, we found an average reaction time of 102 ± 6.9 ms (n = 9), slower than past studies have determined. Visual stimulus resulted in an average reaction time of -4.56 ± 6.0 ms, with over half of individuals responding prior to a visual cue. This result indicates the significance of auditory sensitivity over visual sensitivity in kangaroo rat reaction speed. The discrepancy between studies is likely due to design differences as the original RSS required a reliance on visual cues alone and could not quantify auditory involvement. Future analysis will manipulate acoustic frequency to test the lower limits of kangaroo rat hearing threshold, as well as include anatomical data such as auditory bullae size to better explore the links between morphological adaptation and predation pressure.
