Integrative and Comparative Biology Advance Access originally published online on July 8, 2009
Integrative and Comparative Biology 2009 49(2):178-186; doi:10.1093/icb/icp061
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An evo-devo view on the origin of the backbone: evolutionary development of the vertebrae
The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, E17-336, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
Correspondence: 1E-mail: zhanggj{at}mit.edu
Vertebral columns are a group of diverse axial structures that define the vertebrates and provide supportive, locomotive, protective, and other important functions. The embryonic origin of the first vertebral element in this subphylum, the lamprey arcualia, has remained a puzzle for more than a century although much developmental and genetic progress has been made. The comparative approach is a very powerful tool for studying vertebrate morphological variation and understanding how the novel structures were generated during evolution. Here, I first briefly describe the vertebral structures and their developmental processes in major taxa, and then analyze the most recently published data on the basal vertebrates. Finally, an ontogenetic and phylogenetic origin is proposed. The lamprey may have already evolved a sclerotome, which gave rise to arcualia ontogenetically; whole genome duplications likely promoted the establishment of sclerotomal core genetic program by gene co-options.
From the symposium "Cell-Cell Signaling Drives the Evolution of Complex Traits" presented at the annual meeting of the Society for Integrative and Comparative Biology, January 3–7, 2009, at Boston, Massachusetts.