Tharakan S, Shepherd N, Gower D J, Stanley E L, Felice R N, Goswami A, Watanabe A
Department of Anatomy, New York Institute of Technology, College of Osteopathic Medicine, 100 Northern Boulevard, Old Westbury, NY 11568, USA.
Department of Genetics, Evolution, and Environment, University College London, Gower Street, London, WC1E 6BT, UK.
Integr Org Biol. 2023 Jun 5;5(1):obad022. doi: 10.1093/iob/obad022. eCollection 2023.
How do phenotypic associations intrinsic to an organism, such as developmental and mechanical processes, direct morphological evolution? Comparisons of intraspecific and clade-wide patterns of phenotypic covariation could inform how population-level trends ultimately dictate macroevolutionary changes. However, most studies have focused on analyzing integration and modularity either at macroevolutionary or intraspecific levels, without a shared analytical framework unifying these temporal scales. In this study, we investigate the intraspecific patterns of cranial integration in two squamate species: and . We analyze their cranial integration patterns using the same high-density three-dimensional geometric morphometric approach used in a prior squamate-wide evolutionary study. Our results indicate that and exhibit shared intraspecific cranial integration patterns, with some differences, including a more integrated rostrum in the latter. Notably, these differences in intraspecific patterns correspond to their respective interspecific patterns in snakes and lizards, with few exceptions. These results suggest that interspecific patterns of cranial integration reflect intraspecific patterns. Hence, our study suggests that the phenotypic associations that direct morphological variation within species extend across micro- and macroevolutionary levels, bridging these two scales.
生物体固有的表型关联，如发育和机械过程，是如何引导形态进化的？种内和整个分支的表型协变模式比较，可以为种群水平趋势最终如何决定宏观进化变化提供信息。然而，大多数研究都集中在宏观进化或种内水平上分析整合和模块性，缺乏一个统一这些时间尺度的共享分析框架。在本研究中，我们调查了两种有鳞目物种（此处原文缺失物种名）的种内颅骨整合模式。我们使用先前一项涵盖所有有鳞目动物的进化研究中所采用的相同的高密度三维几何形态测量方法，来分析它们的颅骨整合模式。我们的结果表明，（此处原文缺失物种名）表现出共享的种内颅骨整合模式，但也存在一些差异，包括后者的吻部整合程度更高。值得注意的是，种内模式的这些差异与它们在蛇类和蜥蜴类中的各自种间模式相对应，只有少数例外。这些结果表明，颅骨整合的种间模式反映了种内模式。因此，我们的研究表明，引导物种内形态变异的表型关联跨越了微观和宏观进化水平，连接了这两个尺度。
