Fibrolamellar bone in basal Archosauromorpha: Tracing the evolution of high growth rates.

基底主龙形动物的纤维板层骨：追踪高生长率的进化。

• 批准号: 36841863
• 负责人: Professor Dr. Martin Sander
• 金额: --
• 依托单位: Abteilung Paläontologie
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/36841863?language=en
• 关键词: Fibrolamellar; bone; basal; Archosauromorpha; Tracing

The origin of endothermy is a major issue in the evolutionary biology of vertebrates. Traditionally, it has been explained by selection pressure for increased agility or improved parental care. However, endothermy may also be linked to the evolution of high growth rates, which in turn require high basal metabolic rates, which lead to endothermy. High growth rates appear to be a precondition for the evolution of multi-tone land animals (such as sauropods and elephants) because low growth rates lead to a dramatically decreased likelihood of survival to maturity. The only way to detect high growth rates in an extinct tetrapod is through bone histology. Specifically, fibrolamellar bone tissue serves as a proxy for high growth rates. While our research in the previous funding period has shown that high growth rates were already present in the earliest sauropod dinosaurs, also suggesting they were a prerequisite for gigantism, it is not clear whether these high growth rates evolved due to the selection pressure for increased body size or in the framework of another selective regime. Thus, we need to comprehensively sample the pre-Jurassic and nondinosaurian part of the archosauromorph phylogeny to detect the patterns of occurrence of fibrolamellar bone. At present, a single origin with repeated loss appears equally as likely as a convergent origin in several archosauromorph groups. Understanding the pattern of fibrolamellar bone evolution in basal archosauromorphs will address the hypothesis of high basal metabolic rates being an adaptation to large body size.

恒温动物的起源是脊椎动物进化生物学中的一个重大问题。传统上，它被解释为增加灵活性或改善父母照顾的选择压力。然而，内温性也可能与高生长率的进化有关，这反过来又需要高的基础代谢率，这导致了内温性。高生长率似乎是多色调陆地动物（如蜥脚类动物和大象）进化的先决条件，因为低生长率导致生存到成熟的可能性大大降低。检测灭绝的四足动物高生长率的唯一方法是通过骨骼组织学。具体而言，纤维板层骨组织作为高生长率的代表。虽然我们在上一个资助期的研究表明，最早的蜥脚类恐龙已经存在高生长率，也表明它们是进化的先决条件，但目前尚不清楚这些高生长率是由于增加身体大小的选择压力还是在另一个选择机制的框架内进化而来的。因此，我们需要全面采样的前侏罗纪和nonsauromorphygenesis的一部分，以检测纤维板层骨的出现模式。目前，重复丢失的单一起源似乎与几个主龙形类中的会聚起源一样可能。了解纤维板层骨的模式，在基础的原型龙形骨的演变将解决高基础代谢率是一个适应大的身体尺寸的假设。