Kongtueng Piyamat, Piboon Promporn, Klinhom Sarisa, Aunsan Intorn, Tongser Nontanan, Angkawanish Taweepoke, Nganvongpanit Korakot, Boonsri Burin
Faculty of Veterinary Medicine, Chiang Mai University, Chaing Mai 50100, Thailand.
Thai Elephant Conservation Center, Lampang 52190, Thailand.
Biology (Basel). 2025 Jul 24;14(8):933. doi: 10.3390/biology14080933.
Sexual dimorphism in Asian elephants () is evident in external features, but skeletal differences remain underexplored. This study aimed to examine the skull, scapula, and pelvis using traditional morphometric methods to assess sex-related variation.
Eleven skeletal specimens were analyzed, including nine skulls, eleven pelves, and eighteen scapulae. Linear measurements were obtained using measuring tape and calipers. Statistical analyses included Mann-Whitney U tests, Pearson's correlation, and logistic regression for sex prediction.
No significant differences were found in skull measurements between sexes. However, the pelvis and scapula exhibited notable variation. Significant pelvic parameters included pelvic girdle length ( = 0.024), symphysis length ( = 0.012), and pubis shaft perimeter ( = 0.048). Scapular differences were observed in diagonal breadth, mediolateral width, and spine length. Logistic regression using pelvic measurements yielded 100% accuracy for female classification and 66.67% for males, with an overall prediction accuracy of 90.91%.
The pelvis demonstrated the highest reliability for sex determination. These findings enhance the anatomical understanding of Asian elephants and support applications in conservation, forensic science, and population studies. Future research with larger sample sizes and advanced imaging may improve the precision of morphometric sex prediction models.
亚洲象的两性异形在外部特征上很明显，但骨骼差异仍未得到充分研究。本研究旨在使用传统形态测量方法检查头骨、肩胛骨和骨盆，以评估与性别相关的变异。
分析了11个骨骼标本，包括9个头骨、11个骨盆和18个肩胛骨。使用卷尺和卡尺进行线性测量。统计分析包括曼-惠特尼U检验、皮尔逊相关性分析以及用于性别预测的逻辑回归分析。
两性之间的头骨测量未发现显著差异。然而，骨盆和肩胛骨表现出明显的变异。显著的骨盆参数包括骨盆带长度（P = 0.024）、耻骨联合长度（P = 0.012）和耻骨骨干周长（P = 0.048）。在肩胛骨的对角宽度、内外侧宽度和脊柱长度方面观察到差异。使用骨盆测量进行逻辑回归分析，对雌性的分类准确率为100%，对雄性为66.67%，总体预测准确率为90.91%。
骨盆在性别判定方面显示出最高的可靠性。这些发现增进了对亚洲象解剖结构的理解，并支持在保护、法医学和种群研究中的应用。未来采用更大样本量和先进成像技术的研究可能会提高形态测量性别预测模型的精度。
