Patterns in the bony skull development of marsupials: high variation in onset of ossification and conserved regions of bone contact
Patterns in the bony skull development of marsupials: high variation in onset of ossification and conserved regions of bone contact
复制标题
有袋动物颅骨发育的模式：骨化起始和骨接触保守区域的高度变化
作者：
Stephan N. F. Spiekman;I. Werneburg
有袋类动物的发育是专门针对一个非常短的妊娠期和高度altricial新生儿。因此，有袋类新生儿在出生时表现出与功能限制有关的形态适应。然而，很少有人知道有袋动物头骨发育的变异性及其与形态多样性的关系。我们研究了五种有袋类动物颅骨的发育。骨化发生的相对时间进行了比较，文献数据和骨化序列的有袋类祖先重建平方变化简约。骨化发生的变化范围很大，这意味着无法观察到区分物种的模式。这一发现挑战了传统的研究，集中在骨化的发病作为一个标志物的胚胎发育或作为一个功能代理。我们的研究提出了观察颅骨骨接触的发展时间和它们的进化意义。虽然某些骨接触显示高水平的变化，早期和晚期发展的连接是相当保守和信息。口腔周围的骨头通常是最先连接的，枕骨区域的骨头是最后连接的。我们的结论是，骨接触是最好的研究颅骨发育的骨化发作。
Development in marsupials is specialized towards an extremely short gestation and highly altricial newborns. As a result, marsupial neonates display morphological adaptations at birth related to functional constraints. However, little is known about the variability of marsupial skull development and its relation to morphological diversity. We studied bony skull development in five marsupial species. The relative timing of the onset of ossification was compared to literature data and the ossification sequence of the marsupial ancestor was reconstructed using squared-change parsimony. The high range of variation in the onset of ossification meant that no patterns could be observed that differentiate species. This finding challenges traditional studies concentrating on the onset of ossification as a marker for phylogeny or as a functional proxy. Our study presents observations on the developmental timing of cranial bone-to-bone contacts and their evolutionary implications. Although certain bone contacts display high levels of variation, connections of early and late development are quite conserved and informative. Bones that surround the oral cavity are generally the first to connect and the bones of the occipital region are among the last. We conclude that bone contact is preferable over onset of ossification for studying cranial bone development.
影响因子：
2.6
作者：
Goswami A;Randau M;Polly PD;Weisbecker V;Bennett CV;Hautier L;Sánchez-Villagra MR
通讯作者：
Sánchez-Villagra MR