Atelectasis as a collapse of lung tissue, atelectasis is not synonymous with a pneumothorax, which is a more specific condition that features atelectasis. Acute atelectasis may occur as a post-operative complication or as a result of surfactant deficiency. In premature neonates, this leads to infant respiratory distress syndrome. The term uses combining forms of "atel-" + "ectasis", from , "incomplete" + ἔκτασις, "extension". May have no signs and symptoms or they may include: It is a common misconception that atelectasis causes fever. A study of 100 post-op patients followed with serial chest X-rays and temperature measurements showed that the incidence of
Neoteny in humans weakening of the immune system from upper body musculature competing with the immune system over nutrients. It is argued that the genetic evidence of only a small part of the male population of the time of early agriculture passing on their Y chromosomes can be explained by the heredity of non-neotenic traits causing the male descendants of the non-neotenic men who were not killed by diseases in one generation to die from them in subsequent generations, leaving no Y chromosome evidence of their short term continuation of paternal bloodlines in present humans. Sexual selection for stereotypic masculinity causing most men