Brian K. Hall

Brian Keith Hall is the George S. Campbell Professor of Biology and University Research Professor Emeritus at Dalhousie University in Halifax, Nova Scotia. Hall has researched and extensively written on bone and cartilage formation in developing vertebrate embryos. He is an active participant in the evolutionary developmental biology (EVO-DEVO) debate on the nature and mechanisms of animal body plan formation. Hall has proposed that the neural crest tissue of vertebrates may be viewed as a fourth embryonic germ layer. As such, the neural crest - in Hall's view - plays a role equivalent to that of the endoderm, mesoderm, and ectoderm of bilaterian development and is a definitive feature of vertebrates. As such, vertebrates are the only quadroblastic, rather than triploblastic bilaterian animals. In vertebrates the neural crest serves to integrate the somatic division and visceral division together via a wide range novel vertebrate tissues.

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