Cranial Sexual Dimorphism of Bottlenose Dolphins (genus Tursiops) in Taiwan Waters

• Main Authors: Kuo, Chia-Wen, 郭佳雯
• Other Authors: Jai-Chyic Pei
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/k7287p

碩士 === 國立屏東科技大學 === 野生動物保育研究所 === 95 === Sexual dimorphism may be the outcome of sexual selection, and it is important for intra-species variation. Although the bottlenose dolphin is the most extensively researched cetacean, its sexual dimorphism in Taiwan waters is still poorly known. Thirty-eight skulls of common bottlenose dolphin and 12 skulls of Indo-Pacific bottlenose dolphin from Taiwan waters were examined using Mann-Whitney test and principle components analysis for meristics and 32 cranial morphometric characters. Common bottlenose dolphins revealed significant sexual dimorphism in 2 of all characters in proportion. Female common bottlenose dolphins have proportional longer rostrum than males. None of any cranial characters show sexual dimorphism in Indo-Pacific bottlenose dolphins. No significant difference has been found in meristics in both species. These results indicate that male and female common bottlenose dolphins may have different food habitat and prey, and Indo-Pacific bottlenose dolphin may have limitary home range.