Trachea act as a resonator to amplify sound. In some birds, the tracheal rings are complete, and may even be ossified. In amphibians, the trachea is normally extremely short, and leads directly into the lungs, without clear primary bronchi. A longer trachea is, however, found in some long-necked salamanders, and in caecilians. While there are irregular cartilagenous nodules on the amphibian trachea, these do not form the rings found in amniotes. The only vertebrates to have lungs, but no trachea, are the lungfish and the "Polypterus", in which the lungs arise directly from the pharynx. The word "trachea" is used to
History of beliefs about the human body is important to understanding histories of coercion and control, sex and gender, and other important but culturally varied aspects of human experience. Another prominent voice in the field at the same time was Caroline Walker Bynum, whose 1988 "Holy Feast and Holy Fast" became a landmark study. Both Bynum and Porter noted that during the 1980s Western history of the body research drew on post-structuralist thought, such as Michel Foucault's ideas of biopolitics and biopower, which emphasised that state power is not abstract, but exercised through and over human bodies. But both expressed a concern that research was focusing too