For the past thirty years one of my major interests has been Organic Evolution, and coupled with that for most of this period has been Vertebrate Paleontology, with special emphasis on the earliest vertebrates. Taxonomic study of these primitive forms has been bound to lead to phylogenetic speculation, and of recent years that aspect has dominated my interest. At the same time I have become increasingly concerned with problems of the mode or modes of occurrence of evolutionary changes. Merging these two has given rise to some serious problems.
Proceedings of the Iowa Academy of Science
©1955 Iowa Academy of Science, Inc.
Robertson, George M.
"Problems of Origin and Early Development of the Vertebrates: Skeletal Tissues,"
Proceedings of the Iowa Academy of Science, 62(1), 493-497.
Available at: https://scholarworks.uni.edu/pias/vol62/iss1/62