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Peterson, Kevin J. Division of Biology, California Institute of Technology, Pasadena, California.
- Phylogenetic position
- Origin of characters
- Gene duplication
- Related Primary Literature
- Additional Reading
An outstanding problem in vertebrate paleobiology is the origin of vertebrates, which has been an issue for well over a hundred years. How are vertebrates related to invertebrates; what characteristics are specific to vertebrates in terms of their body plan; and what genetic innovations were necessary in order to develop these vertebrate-specific features remain questions. Answers are not likely to be found in the fossil record of early vertebrates, but require tools that have come into use only recently.
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