Urbanization impact on locomotor performance in Western Fence Lizards (Sceloporus occidentalis)

Xiong, Daisy

008089803@coyote.csusb.edu

Vang, Victoria

Barajas, Ramiro

Corona, Sofia Hernandez

Spain, Emily

Horner, Angela

Putman, Breanna

Department of Biology

California State University

San Bernardino, California USA

As the need for urbanization increases due to rising human population, organisms are forced to adapt at a rapid rate. An ongoing concern for conservation biology is how urbanization impacts organisms and whether some urban adaptations may reduce fitness in natural settings. For this study, we used the Western Fence Lizard (Sceloporus occidentalis) because these lizards are able to live and thrive in both urban and natural habitats and are known to adapt quickly to changing environments. Previous studies showed that although anoles had longer limbs in urbanized habitats Western Fence Lizards have shorter limbs in urbanized habitats, highlighting the importance of studying multiple species in urbanization studies. We captured lizards from three locations in inland Southern California with both urbanized and natural habitats in order to compare the localized effects of urbanization. We hypothesized that limb and toe lengths in Western Fence Lizards would be correlated with locomotion ability, and predicted that urban lizards would have shorter limb and toe lengths, and thus run slower when compared to lizards living in natural habitats. We measured the speed and stride characteristics of each lizard by filming them (480 fps) running across a 90 centimeter trackway. After the lizards ran at least four trials on the track, each lizard was weighed and measured. We digitized speed, stride length, and contact time using DeepLabCut and then compared to the lizard morphology data. Preliminary results suggest that both locality and habitat influence lizard morphology and locomotion, suggesting Western Fence Lizards are highly adaptive.