Data from: Morphological and functional implications of sexual size dimorphism in the Moorish gecko, Tarentola mauritanica

Sexual dimorphism (SD) is a common trait in animals, appearing due to sexual selection, fecundity selection or natural selection promoting sexual niche segregation. To evaluate the relative contribution of these mechanisms in shaping phenotypic patterns, we explored morphological and functional SD in the Moorish gecko, Tarentola mauritanica (Linnaeus, 1758). This species is particularly interesting because the sex of individuals is determined by the incubation temperature of the eggs, which may pose constraints on the expression of SD. Our results indicate the existence of marked SD in T. mauritanica. Males were overall larger than females, and were able to bite harder, but we found no differences between the sexes in climbing capacities. When differences in body size were taken into account, SD became less pronounced, appearing only in relative head dimensions, relative hind limb length and bite force. Different body parts varied under the same static allometric slopes in both sexes, a pattern not very usual in lizards. Put together, our results suggest constraints in the expression of SD in the Moorish gecko, possibly due to either not particularly intense sexual selection, to counter-balancing selection in similar traits in both sexes, or to the mode of sexual determination.

性二态性（Sexual dimorphism, SD）是动物界常见的性状，其形成源于性选择、繁殖力选择或推动生态位分化的自然选择。为评估上述机制在塑造表型模式中的相对贡献，我们针对毛里塔尼亚壁虎（Tarentola mauritanica，Linnaeus, 1758）的形态与功能性性二态性展开了研究。该物种的性别由卵的孵化温度决定，这一特性可能对性二态性的表达形成约束，故而具备独特的研究价值。我们的研究结果显示，毛里塔尼亚壁虎存在显著的性二态性：雄性整体体型大于雌性，且咬合力更强，但二者的攀爬能力并无显著差异。在控制体型差异的影响后，性二态性的表现便趋于弱化，仅在相对头部尺寸、相对后肢长度及咬合力上仍存在差异。两性的不同身体部位均遵循相同的静态异速生长斜率，这一模式在蜥蜴类群中较为罕见。综合来看，我们的研究结果表明毛里塔尼亚壁虎的性二态性表达存在约束，其成因可能包括性选择强度不足、两性同类性状存在平衡选择，或是该物种的性别决定方式。