CNS Evolution: New insight from the mud

Developmental Biology Unit, European Molecular Biology Laboratory, D-69117 Heidelberg, Germany.
Current biology: CB (Impact Factor: 9.57). 09/2009; 19(15):R640-2. DOI: 10.1016/j.cub.2009.06.020
Source: PubMed


Whether the highly centralised nervous systems of chordates and protostomes arose from a common ancestral precursor or independently has been a long-standing debate. Now, analysis of neural gene expression in an evolutionarily important chordate outgroup--the sand-dwelling, hemichordate acorn worms--reveals the presence of a central and peripheral nervous system, suggesting a common origin of central nervous systems.

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Available from: Elia Benito, Sep 29, 2014
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    • "Eventually , the integration of sensory neural nets led to the evolution of the central nervous system. The question whether the formation of a primitive nervous system occurred in more than one lineage or emerged singularly in one last common ancestor, the urbilaterian, is subject to continuing debate [36]. However, recent genome-wide studies involving comb-jellies have not only based this phylum of non-bilaterian animals at the very base of the tree of life, but are also suggestive of an independent emergence of a nervous system in this ancient clade [37] [38] [39]. "
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