After volume 33, this book series was replaced by the journal "Evolutionary Biology." Please visit www.springer.com/11692 for further information. This volume continues bringing to readers the findings of eminent evolutionary biologists and paleobiologists. Among the topics discussed in this book are the origin of the dermal skeleton in conodont chordates, patterns of nucleotide substitution and codon usage in plasmid DNA evolution, a model to explain phenotype stability in functional systems, and inter-island speciation of Hawaiian biota.