Longitudinal fissure Longitudinal fissure The longitudinal fissure (or cerebral fissure, median longitudinal fissure, or interhemispheric fissure) is the deep groove that separates the two hemispheres of the vertebrate brain. The medial surfaces of the two hemispheres are as similarly convoluted by gyri and sulci as is the outer surface of the brain. It is thought that a majority of existing animals, including Homo sapiens, have evolved from a common wormlike ancestor that lived around 600 million years ago, called the urbilaterian. A bilaterian animal is one that has symmetrical left and right body halves. While it is still debated whether this species
History of beliefs about the human body body has in the world. All cultural ideals of the body in the early modern period deal with deficiencies and disorders within a body, commonly told through a male ideal. Ideas of the body in the early modern period form the history of how bodies should be and how to correct the body when something has gone wrong. Therefore, early modern conceptions of the body were not biological as there was not a restrictive biological view of the human body as established by modern science. Conceptions of the body are primarily either eastern, based in China and involving practices such