Most Notosuchia were active terrestrial predators. A few were semi-aquatic, or were insectivorous, omnivorous or herbivorous. A question relative to their thermometabolism remains to be answered: were Notosuchia warm-blooded? Here we use quantitative bone palaeohistology to answer this question. Two variables were used as proxies to infer thermometabolism: resting metabolic rate and red blood cell dimensions. Resting metabolic rate was inferred using relative primary osteon area and osteocyte size, shape and density. Blood cell dimensions were inferred using harmonic mean canal diameter and minimum canal diameter. All inferences were performed using phylogenetic eigenvector maps. Both sets of analyses suggest that the seven species of Notosuchia sampled in this study were ectotherms. Given that extant Neosuchia (their sister group) are also ectotherms, and that archosaurs were primitively endotherms, parsimony suggests that endothermy may have been lost at the node Metasuchia (Notosuchia–Neosuchia) by the Early Jurassic. Semi-aquatic taxa such as Pepesuchus may have had thermoregulatory strategies similar to those of recent crocodylians, whereas the terrestrial taxa (Araripesuchus, Armadillosuchus, Iberosuchus, Mariliasuchus, Stratiotosuchus) may have been thermoregulators similar to active predatory varanids. Thermal inertia may have contributed to maintaining a stable temperature in large notosuchians such as Baurusuchus.

中文翻译：

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Notosuchia（Pseudosuchia：Crocodylomorpha）是热血的吗？古组织学分析提示等温

大多数诺奇氏菌是活跃的陆地掠食者。少数是半水生的，或者是食虫的，杂食的或草食性的。关于它们的热代谢的一个问题有待回答：诺氏菌属是温血的吗？在这里，我们使用定量骨古组织学来回答这个问题。有两个变量被用作推断热代谢的代表：静息代谢率和红细胞大小。静息代谢率由相对的原骨面积和骨细胞的大小，形状和密度来推断。使用谐波平均根管直径和最小根管直径推断血细胞尺寸。所有推论均使用系统发育特征向量图进行。两组分析都表明，在这项研究中采样的7种Notosuchia是放热的。鉴于现存的新鳄属（其姊妹群）也是等温线，而始祖龙原本是吸热体，因此简约性表明，侏罗纪早期在metasuchia（Notosuchia–Neosuchia）结点可能失去了吸热性。半水生类群Pepesuchus可能具有类似于近期鳄类动物的温度调节策略，而陆生类群（Araripesuchus，Armadillosuchus，Iberosuchus，Mariliasuchus，Stratiotosuchus）可能是类似于活性捕食性变体的温度调节剂。热惯性可能有助于维持诸如Baurusuchus之类的大型公证人的稳定温度。