Instructions: In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.
Input: The diaphragm is a muscle that is at the bottom of the ribcage of mammals .
Output:
The thoracic diaphragm , or simply the diaphragm , is a sheet of internal skeletal muscle in humans and other mammals that extends across the bottom of the thoracic cavity .