Morphological and developmental study on the evolution of the head (especially brain and inner ear) and neck in theropod dinosaurs

在美国的一家博物馆里，研究人员观察了第一批经过清理和染色的美洲鳄胚胎标本的骨化模式序列。此外，对家鸡的受精卵进行孵化，并定期固定，直到孵化前。这些标本使用CT扫描仪扫描，以获得骨化序列的数据。所得序列与先前发表的其他鸟类的序列一致。此外，我们还在美国和阿根廷的博物馆中观察了从晚三叠世到白垩纪的祖龙化石标本，并获得了它们的脑壳和颈部的形态学数据。基于这些数据，现在正在制作一个特征数据矩阵，用于分析祖龙这些骨骼部分的进化模式。

A first, cleared-and-stained specimens of embryos of the American Alligator housed at a museum in the U.S. was observed for sequences of ossification patterns. Furthermore, fertilized eggs of the domestic chickens were incubated and were periodically fixed until immediately before hatching. These specimens were scanned using a CT scanner for obtaining data on ossification sequences. The obtained sequence is consistent with those of other birds published previously. In addition, fossil archosaur specimens ranging from the Late Triassic through Cretaceous in age were observed in museums in the U.S. and Argentina and morphological data on their braincases and necks were obtained. Based on these data, a character data matrix is now in making for analyzing patterns of evolution in these skeletal parts in archosaurs.