Selection and constraints in the ecomorphological adaptive evolution of the skull of living Canidae (Carnivora, Mammalia)

The association between phenotype and ecology is essential for understanding the environmental drivers of morphological evolution. This is a particularly challenging task when dealing with complex traits such as the skull, where multiple selective pressures are at play and evolution might be constrained by ontogenetic and genetic factors. In the present contribution I integrate morphometric tools, comparative methods and quantitative genetics to investigate how ontogenetic constraints and selection might have interacted during the evolution of the skull in extant Canidae. The results confirm that the evolution of cranial morphology was largely adaptive and molded by changes in diet composition. While the investigation of the adaptive landscape reveals two main Selective Lines of Least Resistance (one associated with size and one associated with functional shape features), rates of evolution along size were higher than those found for shape dimensions, suggesting the influence of constra...

表型（phenotype）与生态学之间的关联对于理解形态演化的环境驱动因素至关重要。在研究颅骨这类复杂性状时，这项任务尤其具有挑战性——因为多种选择压力共同作用，且演化可能受到个体发育（ontogenetic）和遗传因素的限制。在本研究中，我整合了形态测量学工具、比较方法和数量遗传学（quantitative genetics），以探究现存犬科动物（Canidae）颅骨演化过程中个体发育限制与选择压力如何相互作用。结果证实，颅骨形态的演化在很大程度上具有适应性，并受到饮食组成变化的塑造。尽管对适应景观的研究揭示了两条主要的“最小阻力选择线”（Selective Lines of Least Resistance）——一条与体型相关，另一条与功能形态特征相关，但体型维度的演化速率高于形态维度，这表明存在约束...