Mayo Clinic, Department of Physiology & Biomedical Engineering, Rochester, Minnesota, USA.
Compr Physiol. 2019 Mar 14;9(2):715-766. doi: 10.1002/cphy.c180012.
Symmorphosis is a concept of economy of biological design, whereby structural properties are matched to functional demands. According to symmorphosis, biological structures are never over designed to exceed functional demands. Based on this concept, the evolution of the diaphragm muscle (DIAm) in mammals is a tale of two structures, a membrane that separates and partitions the primitive coelomic cavity into separate abdominal and thoracic cavities and a muscle that serves as a pump to generate intra-abdominal (P ) and intrathoracic (P ) pressures. The DIAm partition evolved in reptiles from folds of the pleural and peritoneal membranes that was driven by the biological advantage of separating organs in the larger coelomic cavity into separate thoracic and abdominal cavities, especially with the evolution of aspiration breathing. The DIAm pump evolved from the advantage afforded by more effective generation of both a negative P for ventilation of the lungs and a positive P for venous return of blood to the heart and expulsive behaviors such as airway clearance, defecation, micturition, and child birth. © 2019 American Physiological Society. Compr Physiol 9:715-766, 2019.
共生现象是一种生物设计的经济性概念，即结构特性与功能需求相匹配。根据共生现象，生物结构永远不会过度设计以超过功能需求。基于这一概念，哺乳动物横膈膜肌肉（DIAm）的进化是两个结构的故事，一个是将原始体腔分隔成独立的腹腔和胸腔的膜，另一个是作为泵的肌肉，用于产生腹腔内（P）和胸腔内（P）的压力。DIAm 分隔在爬行动物中从胸膜和腹膜的褶皱中进化而来，这是由于将较大体腔中的器官分隔成独立的胸腔和腹腔的生物学优势所驱动的，尤其是随着抽吸呼吸的进化。DIAm 泵的进化源于更有效地产生负压（P）以通风肺部和正压（P）以将血液回流到心脏以及呼气行为（如气道清除、排便、排尿和分娩）的优势。© 2019 美国生理学会。综合生理学 9：715-766，2019 年。
