Mechanisms of Coexistence of Two Agamid Lizards in Northern Taiwan: An Eco-morphology Perspective

• Main Authors: Shao-Min Yang, 楊邵閔
• Other Authors: Yu-Teh Lin
• Format: Others
• Language: en_US
• Online Access: http://ndltd.ncl.edu.tw/handle/92349658663775775614

碩士 === 國立臺灣大學 === 生態學與演化生物學研究所 === 97 === The geographic distributions of Japalura swinhonis and Japalura polygonata xanthostoma overlap in northern Taiwan. Two species coexist in some locations, but not others. I investigated whether differences in morphology (standardized for overall sizes) occurred between sympatric and allopatric populations (a precondition for character displacement). I found morphological differences in head height and head dimensions in the field. In the laboratory test, I found head dimension can affect bite force and fighting ability, and it can affect sprint ability on different size of perch. When the two species competed for perch resource, male Japalura swinhonis had greater head size and bite force, but they suffered greater reduction in sprint ability than Japalura polygonata xanthostoma as perch incline change. It suggested a trade-off existed between fighting and motion ability in the two species, therefore they could coexist in some locations.