It is with pleasure that the editors dedicate this volume to William Camp bell Steere, one of the founding editors of Evolutionary Biology. As Dr. Steere approaches his eightieth birthday we include in the volume a brief biography and a complete bibliography of his publications in celebration of his contributions to the biological sciences. The Editors Ix Contents 1. William Campbell Steere: An Outline of His Life and Continuing Career . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 William R. Buck Bibliography of Publications of William Campbell Steere 5 2. Biochemical Systematics: II. A Reprise ....... . . . . . . . .. . . 25 David E. Giannasi and Daniel J. Crawford Introduction ........................................ 25 Micromolecules ..................................... 28 Flavonoids ....................................... 28 Terpenoids ....................................... 49 Alkaloids . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . 83 . . . . . . . . . Other Micromolecules of Chemosystematic Interest .. . . . . .. . 92 Micromolecules of Specific Plant Groups ................. 96 Lichens . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 104 . . . . . . . . . . New Approaches in Micromolecular Chemosystematics ...... 112 C Metabolism. . . . . . . . . . . . . . . . . . . . . . . . . .. . . 118 . . . . . . . . 4 Paleobiochemistry .................................. 120 Micromolecules: Biological and Evolutionary Considerations ................................. 127 Macromolecules ..................................... 132 Electrophoresis .................................... 133 Amino Acid Sequences .............................. 155 Serology ......................................... 167 Nucleic Acids ..................................... 182 Conclusions and Future Prospects . . . . . . . . . . . . . . . . .. . . 209 . . . . Micromolecules . . . . . . . . . . . . . . . . . . . . . . . . .. . . 209 . . . . . . . . Macromolecules . . . . . . . . . . . . . . . . . . . . . . . . .. . . 211 . . . . . . . . References ......................................... 213 xl xii Contents 3. Species Selection As a Causal Process ......... . . . . . . .. . . 249 Norman L. Gilinsky Introduction ........................................ 249 Differential Rates of Extinction . . . . . . . . . . . . . . . . . .. . . 251 . . . . . Differential Rates of Speciation: General Problems ........... 252 Differential Rates of Speciation: A Case for Reducibility ....... 254 Differential Rates of Speciation: A Case for Irreducibility Speciation via the Founder Principle . . . . . . . . . . . . .. . . 257 . . . Discussion ......................................... 262 Possible Examples of Species Selection: Hawaiian Drosophilidae ............................ 262 Possible Examples of Species Selection: Tertiary Neogastropoda ............................ 263 The Snail Example: Another Viewpoint ..... . . . . . . . . .. . . 267 . Species Selection and Randomness ..................... 268 Species Selection and Punctuated Equilibria . . . . . . . . . .. . . 269 . ."

Evolutionary Biology, of which this is the eighteenth volume, con tinues to offer its readers a wide range of original articles, reviews, and commentaries on evolution, in the bro dest sense of that term. The topics of the reviews range from anthropology and behavior to molecular biology and systematics. In recent volumes, a broad spectrum of articles have appeared on such subjects as natural selection among replicating molecules in vitro, mate recognition and the reproductive behavior of Drosophila, molecular systematics ofCrocodilia, evolution of the monocotyledons, and the com munication network made possible among even distantly related genera of bacteria by plasmids and other transposable elements. Articles such as these, often too long for standard journals, are the stuff of Evolutionary Biology. The editors continue to solicit manuscripts on an international scale in an effort to see that everyone of the many facets of biological evolution is covered. Manuscripts should be sent to anyone of the following: Max K. Hecht, Department of Biology, Queens College of the City University of New York, Flushing, New York 11367; Bruce Wallace, Department of Biology, Virginia Polytechnic Institute and State University, Blacks burg, Virginia 24061; Ghillian T. Prance, New York Botanical Garden, Bronx, New York 10458."

Sixteen volumes and one supplement have now appeared in the series known as Evolutionary Biology. The editors continue to seek critical re views, original papers, and commentaries on controversial topics. It is our aim to publish papers primarily of greater length and depth than those normally published by society journals and quarterlies. The editors make every attempt to solicit manuscripts on an international scale and to see that every facet of evolutionary biology-classical or modern-is cov ered. Manuscripts should be sent to anyone of the following: Max K. Hecht, Department of Biology, Queens College of the City University of New York, Flushing, New York 11367; Bruce Wallace, Department of Biology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061; Ghillean T. Prance, New York Botanical Garden, Bronx, New York 10458. The Editors vii Contents 1. Darwinian Selection of Self-Replicating RNA Molecules 1 Christ( r K. Biehricher Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Replication of Virus RNA in Vitro. . . . . . . . . . . . . . . . . . . . . . . . 2 Extracellular Darwinian Experiments. . . . . . . . . . . . . . . . . . . . . . 5 Characterization of the QI3 Replicase. . . . . . . . . . . . . . . . . . . . . . 9 Nonviral RNA Templates of QI3 Replicase. . . . . . . . . . . . . . . . . . II The Mechanism of RNA Replication . . . . . . . . . . . . . . . . . . . . . . 14 Initiation of Replication and Template Specificity . . . . . . . . . . . 14 Mechanism of Replica Chain Elongation. . . . . . . . . . . . . . . . . . 17 Termination of Replication. . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Replication of RNA Variants . . . . . . . . . . . . . . . . . . . . . . . . . . 21 The Quasispecies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 De NOl'O Synthesis of Self-Replicating RNA. . . . . . . . . . . . . . . . . 27 The Mechanism of Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Selection in the Exponential Growth Phase. . . . . . . . . . . . . . . . 32 Selection in the Linear Growth Phase. . . . . . . . . . . . . . . . . . . . 35 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Appendix I. Replication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Appendix II. The Quasispecies. . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Appendix III. Selection under Various Conditions . . . . . . . . . . . . 44 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ."

Evolutionary Biology, of which this is the twenty-first volume, continues to offer its readers a wide range of original articles, reviews, and com mentaries on evolution, in the broadest sense of that term. The topics of the reviews range from anthropology and behavior to molecular biology and systematics. In recent volumes, a broad spectrum of articles have appeared on such subjects as evolution of the bacterial genome, biochemical system atics in plants, a discussion of species selection, and development and evolution of the vertebrate limb. Articles such as these, often too long for standard journals, are the material for Evolutionary Biology. The editors continue to solicit manuscripts on an international scale in an effort to see that everyone ofthe many facets of biological evolution is covered. Manuscripts should be sent to anyone of the following: Max K. Hecht, Department of Biology, Queens College of the City University of New York, Flushing, New York 11367; Bruce Wallace, Department of Biology, Virginia Polytechnic Institute and State University, Blacks burg, Virginia 24061; or Ghillian T. Prance, New York Botanical Garden, Bronx, New York 10458."

This volume is the result of a NATO Advanced Study Institute held in England at Kingswood Hall of Residence, Royal Holloway College (London University), Surrey, during the last two weeks of July, 1976. The ASI was organized within the guide lines laid down by the Scientific Affairs Division of the North Atlantic Treaty Organization. During the past two decades, significant advances have been made in our understanding of vertebrate evolution. The purpose of the Institute was to present the current status of our know ledge of vertebrate evolution above the species level. Since the subject matter was obviously too broad to be covered adequately in the limited time available, selected topics, problems, and areas which are applicable to vertebrate zoology as a whole were reviewed. The program was divided into three areas: (1) the theory and methodology of phyletic inference and approaches to the an alysis of macroevolutionary trends as applied to vertebrates; (2) the application of these methodological principles and an alytical processes to different groups and structures, particular ly in anatomy and paleontology; (3) the application of these re sults to classification. The basic principles considered in the first area were outlined in lectures covering the problems of character analysis, functional morphology, karyological evidence, biochemical evidence, morphogenesis, and biogeography."