Sweeney Granite Mountains Desert Research Center

03 Jun, 01 PM - 10 Jun, 01 PM

The goal of this research is to understand interactions between feet and granular media (GM) during fast locomotion. Within a single step, GM alternates between solid-like and fluid-like states with potentially drastic consequences on running performance. How foot kinematics instigate state changes is unknown, yet is critically important for survival. I hypothesize that animals specialized for sandy environments will adjust foot movements to facilitate material solidification and achieve greater running speeds, whereas among non-specialists, adjustments will not increase material solidification resulting in slower running speeds and increased slippage. To test these hypotheses, using the lizards noosing method, I will collect individuals of a species each of a sand specialist (Callisaurus draconoides) and desert generalist (Gambelia wislizenii, Crotaphytus bicinctores). Using individuals of these species, I will quantify subsurface foot kinematics using X-Ray Reconstruction of Moving Morphology (XROMM), which combines 3D x-ray videos with skeletal CT scans, in collaboration with Dr. Callum F. Ross, Professor at The University of Chicago and Facility Director of The University of Chicago XROMM (UC-XROMM) Facility. Individuals will run on level and inclined (~30°) trackways filled with poppy seeds. At the angle of repose (~30°), GM will fluidize with the slightest stress, rendering running at these angles extremely challenging. I have selected similarly-shaped species with similarly-shaped feet so that differences I detect among performance are more likely due to foot kinematics than morphology. Lizards are an excellent model system because they occupy and specialize to a wide range of terrestrial niches. In the desert, for example, they are found on hard-packed sand and lava flows, to flowing sand dunes. My results will identify which aspects of foot kinematics instigate state transitions in GM to maintain high performance locomotion on complex terrain.

Visit #61820 @Sweeney Granite Mountains Desert Research Center

Approved

Under Project # 42510 | Research

Lizards running on flowable ground

graduate_student - Temple University

Reservation Members(s)

Tonia Hsieh Jun 3 - 7, 2019 (5 days)
Group of 3 Other Jun 3 - 7, 2019 (5 days)
Diana Mantilla Jun 3 - 10, 2019 (8 days)
Elizabeth Tucker Jun 3 - 10, 2019 (8 days)
Mark Walker Jun 3 - 10, 2019 (8 days)

Reserve Resources(s) | Create Invoice

Allanson Center Loft (Research Use) 4 Jun 3 - 10, 2019
Allanson Center West Cabin (Research Use) 2 Jun 3 - 7, 2019