Leigh Steven R
Department of Anthropology, 109 Davenport Hall, University of Illinois, Urbana, IL 61801, USA.
J Hum Evol. 2007 May;52(5):536-58. doi: 10.1016/j.jhevol.2006.11.016. Epub 2007 Feb 20.
Recent advances in developmental biology reveal that patterns of morphological development, even during early phases, may be highly susceptible to evolutionary change. Consequently, developmental data may be uninformative with regard to distinguishing homology and homoplasy. The present analysis evaluates postnatal ontogeny in papionin primates to test hypotheses about homology and homoplasy during later periods of development. Specifically, the analysis studies the allometric bases of craniometric resemblances among four papionin genera to test the hypothesis that homoplasy in adult cranial form, particularly of baboons (Papio) and mandrills (Mandrillus), is underwritten by divergent patterns of development. Bivariate and multivariate allometric analyses demonstrate that the developmental patterns in Papio baboons diverge markedly from ontogenetic allometric trajectories in other papionin species. The resemblances between Papio and Mandrillus (assuming that patterns of development in smaller papionins are ancestral) are largely consequences of perinatal increases in relative brain size in juvenile Papio. Postnatal growth to large size and strong negative allometry of neurocranial form results in shape similarities because developmental pathways for large papionin genera intersect. Analyses show that allometric data may not be particularly informative in revealing homoplasy. However, placed into proper phylogenetic context, such data illustrate derived patterns of development that may reflect critically important life-history or ontogenetic adaptations.
发育生物学的最新进展表明，形态发育模式，即使在早期阶段，也可能极易受到进化变化的影响。因此，发育数据在区分同源性和同功性方面可能并无助益。本分析评估了狒狒科灵长类动物的出生后个体发育，以检验关于发育后期同源性和同功性的假设。具体而言，该分析研究了四个狒狒科属颅骨测量相似性的异速生长基础，以检验这一假设：成年颅骨形态的同功性，尤其是狒狒属（Papio）和山魈属（Mandrillus）的同功性，是由不同的发育模式所导致的。双变量和多变量异速生长分析表明，东非狒狒的发育模式与其他狒狒科物种的个体发育异速生长轨迹明显不同。狒狒属和山魈属之间的相似性（假设较小狒狒科物种的发育模式是祖先型的）在很大程度上是幼年东非狒狒围产期相对脑容量增加的结果。出生后生长至大型化以及神经颅骨形态的强烈负异速生长导致了形状上的相似性，因为大型狒狒科属的发育途径相交。分析表明，异速生长数据在揭示同功性方面可能并非特别有用。然而，置于适当的系统发育背景下，此类数据说明了可能反映至关重要的生活史或个体发育适应性的衍生发育模式。
