The origin of the unique body plan of turtles has long been one of the most intriguing mysteries in evolutionary morphology. Discoveries of several new stem-turtles, together with insights from recent studies on the development of the shell in extant turtles, have provided crucial new information concerning this subject. It is now possible to develop a comprehensive scenario for the sequence of evolutionary changes leading to the formation of the turtle body plan within a phylogenetic framework and evaluate it in light of the ontogenetic development of the shell in extant turtles. The fossil record demonstrates that the evolution of the turtle shell took place over millions of years and involved a

中文翻译：

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龟体图的起源：来自化石和胚胎的证据

长期以来，海龟独特的身体计划的起源一直是进化形态学中最有趣的谜团之一。几种新干龟的发现，以及最近对现存龟壳发育研究的见解，提供了有关这一主题的重要新信息。现在可以在系统发育框架内为导致龟体计划形成的进化变化序列开发一个综合方案，并根据现存龟壳的个体发育发展对其进行评估。化石记录表明，龟壳的进化经历了数百万年，涉及