Extended Data Figure 9: Visceral cavities of S. xenarthrosus with internal organs.
From: A Cretaceous eutriconodont and integument evolution in early mammals
a, Detail of the visceral cavities of MCCMLH30000B with separation of the anterior thoracic cavity (TC) containing the lungs (LU), and the posterior abdominal cavity (AC) containing the liver (LI). Dashed line represents the diaphragm. SE, sternal elements. b, Lung tissue in the anterior part of the thoracic cavity. c, Peripheral conducting and acinar airways of the lungs with typical dichotomous structure of the bronchial tree. d, Peripheral conducting and acinar airways of the lungs from transferred slab MCCMLH30000A under translucent light. e, f, Details of the peripheral conducting airway dichotomies (DI) and acinar structures (ACI) of the lungs.
