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
Mermaids: The Body Found is an example of what is known as docufiction, in which documentary style and programming elements are combined with fictional - or sometimes less egregiously speculative - science and fiction. This type of programming receives particular criticism when, as in the original broadcast of "Mermaids: The Body Found", there are only a few, easily missed disclaimers to indicate the speculative nature of the programming. On the contrary, the serious tone of the majority of the presentation implied that it was a factual documentary. The first airings of the two "Mermaids" programs apparently fooled millions of people and also drew some