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Part of the embryonic brain
Hindbrain
Diagram depicting the main subdivisions of the embryonic vertebrate brain. These regions will later differentiate into forebrain, midbrain and hindbrain structures.
The hindbrain is homologous to a part of the arthropod brain known as the sub-oesophageal ganglion, in terms of the genes that it expresses and its position in between the brain and the nerve cord. It has been suggested that the hindbrain first evolved in the urbilaterian—the last common ancestor of chordates and arthropods—between 570 and 555 million years ago.
Poretti, Andrea; Alber, Fabienne Dietrich; Bürki, Sarah; Toelle, Sandra P.; Boltshauser, Eugen (January 2009). "Cognitive outcome in children with rhombencephalosynapsis". European Journal of Paediatric Neurology. 13 (1): 28–33. doi:10.1016/j.ejpn.2008.02.005. PMID18407532.