Foreword - Ernst Mayr
CHAPTER 1. Variation and Viability: Central Concepts in Biology- Benedikt Hallgrímsson & Brian K. Hall
CHAPTER 2. Variation from Darwin to the Modern Synthesis, by Peter J. Bowler
Introduction
I. Variation before Darwin
II. Darwin and Variation
III. Alternative Theories of Variation and Evolution
IV. Neo-Darwinism
V. The Evolutionary Synthesis
VI. Conclusions
CHAPTER 3. The Statistics of Variation, by Leigh Van Valen
Abstract
Introduction
I. Absolute Variation: Univariate Case
II. Absolute Variation: Multivariate Case
III. Relative Variation: Univariate Case
IV. Relative Variation: Multivariate Case
V. Dimensionality of Variation
VI. Tightness
VII. Measurement Error and Single Specimens
CHAPTER 4. Landmark Morphometrics and the Analysis of Variation, by Joan T. Richtsmeier, Subhash R. Lele and Theodore M. Cole, III
Introduction
I. Coordinate Data and the Coordinate System
II. The General Perturbation Model for Landmark Variation
III. Proper Elimination of Nuisance Parameters using a Coordinate System Invariant Method of Estimation
IV. Adding Assumptions to the Perturbation Model
V. Conclusions
CHAPTER 5. Variation in Ontogeny, by D.C. Jones and R.Z. German
Introduction
I. Measuring Variation
A. Data
B. Levels of Variation in Data on Growth and Protein Malnutrition
C. Measuring within Individual Variation
D. Among Individual Variation
E. Variation Between Treatment Groups
II. Results
A. Factor Differences for Within Individual Variation
B. Factor Differences for Among Individual Variation
III. Discussion
A. Within Individual Variation
B. Between or among Individual Variation
C. Variation across hierarchial levels
IV. Conclusions
CHAPTER 6. Constraints on Variation from Genotype through Phenotype to Fitness, by Lauren Ancel Meyers
Introduction
I. RNA Evolutionary Model
II. Evolving Constraints on Variation in RNA
III. Mechanistic Constraints
A. The spectrum of mutational constraints
B. The Evolution of Mutational Constraints
IV. Epistatic Constraints
A. The spectrum of epistatic constraints
B. The evolution of epistatic constraints
V. Viability Constraints
VI. Modularity: A Way out of the Constraints
CHAPTER 7. Developmental Origins of Variation, by Ellen W. Larsen
Introduction
I. Does Intrinsic Developmental Variation Exist?
II. Intrinsic Variation in Different Environments
III. Potential Origins of Intrinsic Developmental Variation
A. Noise
IV. An Example of Noise in Eukaryotic Transcription
V. Noisy Bicoid Gene Expression in Fruit Flies
VI. Noise in Asymmetry Production
VII. Noisy Implication for Evolution
VIII. Networks
IX. Morphogenetic Fields a Potential Source of Variation
X. Implications
XI. Summary
CHAPTER 8. Canalization, Cryptic Variation and Developmental Buffering: A Critical Examination and Analytical Perspective, by Ian Dworkin
Introduction
I. A Review of the Reviews
II. Empirical Concerns for the Study of Canalization
A. The amount of genetic variation must be controlled between lines/populations
B. The need for multiple, independent samples
C. Genetic background must be controlled for comparisons between treatments
III. Definitions of Canalization
IV. Reaction Norm of the Mean (RXNM) Definition of Canalization
V. The Variation Approach to Canalization
VI. Partitioning Sources of Variation
VII. Inferring Canalization: When is a trait Canalized?
VIII. What are the appropriate tests for making statistical inferences about Canalization?
IX. In the Interim…
X. Analysis for the RXNM Approach
XI. The Analysis of Cryptic Genetic Variation
XII. Mapping Cryptic Genetic Variants
XIII. Is the Genetic Architecture of Cryptic Genetic Variation different from that of other Genetic Variation involved with Trait Expression?
XIV. Now that I have all of this Cryptic Genetic Variation, what do I do with it?
XV. The future for studies of Canalization
CHAPTER 9. Mutation and Phenotypic Variation: Where is the connection Capacitators, Stressors, Phenotypic Variability and Evolutionary Change, by Ary A. Hoffmann and John A. McKenzie
Abstract
Introduction: Variability and Limits
I. Mutators, Recombinators, Stressors and Genetic Variability
II. Recombination
III. The Impact of New Mutants and Recombinants – Canalization and Capacitators
IV. In Search of Capacitators: Genes that influence Developmental Stability and Canalization
V. Capacitators, Stressors, and Quantitative Variation
VI. Do we need Cariability Generators?
VII. Concluding Remarks: Experimental Programs for Defining the Role of Variability Generators
CHAPTER 10. Within Individual Variation: Developmental Noise versus Developmental Stability, by Katherine E. Willmore and Benedikt Hallgrímsson
Introduction
I. Causes of Developmental Noise
A. Causes of Developmental Noise at the Molecular Level
B. Causes of Developmental Noise at the Developmental Systems Level
C. Causes of Developmental Noise at the Organismal Level
II. Mechanisms of Developmental Stability
A. Mechanisms of Developmental Stability at the Molecular Level
B. Mechanisms of Developmental Stability at the Developmental Systems Level
C. Mechanisms of Developmental Stability at the Organismal Level
III. Implications
CHAPTER 11. Developmental Constraints, Modules and Evolvability, by Christian Peter Klingenberg
Abstract
Introduction
I. Evolvability and Constraints
II. Integration and Modularity
III. Developmental Origins of Covariation among Traits
IV. Developmental Interactions and Pleiotropy
V. Evolution of Pleiotropy and Developmental Interactions
VI. Modularity of Pleiotropic Effects: Inherent in Developmental Systems or Evolved Property?
VII. From Pleiotropic Gene Effects to G Matrices
VIII. G Matrices, Constraints, and Evolutionary Dynamics
IX. Perspective: Developmental Processes and Evolutionary Constraints
CHAPTER 12. Developmental Regulation of Variability, by Miriam Zelditch
Introduction
I. Empirical Patterns
II. The Ontogeny of Variation in Male Norway Rat Cranial Shape
III. Biological Patterns Versus Artifacts
A. Morphological Sampling
B. Life-History/Developmental Rate
IV. Mechanisms Generating and Regulating Craniofacial Shape Variance
V. Targeted Growth
VI. Organismal Developmental Timing
VII. Variation in Relative Developmental Timing of Modules
VIII. Neural Regulation of Musculoskeletal Interactions
IX. Canalized Shape as an Epiphenomenon
CHAPTER 13. Role of Stress in Evolution: From Individual Adaptability to Evolutionary Adaptation, by Alexander Badyaev
Introduction
I. Evolution of Response to Stress
A. Detection and Avoidance
II. Evolutionary Consequences of Stress
A. Stress-induced Variation
III. Buffering, Accommodating, and Directing Stress-Induced Variation
IV. Inheritance
V. Evolutionary Adaptation
VI. Conclusions
CHAPTER 14. Environmentally Contingent Variation: Phenotypic Plasticity and Norms of Reaction, by Sonia Sultan and Steve Stearns
Introduction
I. Plasticity Concepts
II. Specific Types of Plasticity
III. Reaction Norms
IV. Parental Effect Reaction Norms (Cross-Generational Plasticity)
V. Imprinted Reaction Norms
VI. Iterated Reaction Norms
VII. Dynamic Reaction Norms
VIII. Photomorphogenetic Plasticity in Plants
IX. Adaptive Plasticity for Timing of Amphibian Metamorphosis
X. Mediation of Phenotypic Expression
XI. Genetic Variation and the Evolution of Plasticity
A. How Plasticity interacts with conserved developmental patterns
XII. Genetic Causation and the Butterfly Wing: A More complicated picture
XIII. The Same Networks may give rise to both Plasticity and Constraint
A. What effects does plasticity have on populations and communities?
B. Research Agenda
CHAPTER 15. Variation and Life History Evolution, by Derek A. Roff
Introduction
I. Phenotypic Variation in a Constant Environment
A. Heterozygous advantage
B. Antagonistic pleiotropy
C. Frequency-dependent selection
II. Phenotypic Variation in a Stochastic Environment
A. Temporal variation
B. Spatial variation
C. Spatial and temporal variation
III. Predictable Environments
A. Temporal variation
B. Spatial variation
IV. Concluding Comments
CHAPTER 16. Antisymmetry, by A. Richard Palmer
Introduction
I. Asymmetry Terminology
A. Terms for Subtle Asymmetries
B. Terms for Conspicuous Asymmetry in an Individual
C. Terms for the Orientation of Bilateral or Spiral Asymmetries
D. Terms for Conspicuous Asymmetries in a Population or Species
II. The History of Antisymmetry
III. Taxomonic Distribution and Functional Significance of Antisymmetry
A. Plants
B. Cnidaria
C. Mollusca
D. Annelida
E. Arthropoda-Chelicerata
F. Arthropoda-Crustacea
G. Arthropoda-Insecta
H. Brachiopods
I. Bryozoa
J. Echinodermata
K. Chordata
IV. Development and Regeneration of Asymmetry in Antisymmetric Species
A. Ontogeny
V. Regeneration of Missing Antimeres
VI. Inheritance of Direction in Antisymmetric Species
VII. Inheritance of Direction in Directionally Asymmetric Species
VIII. Evolutionary Significance of Antisymmetry
IX. What Next?
CHAPTER 17. Variation in Structure and its Relationship to Function: Correlation, Explanation and Extrapolation, by Anthony P. Russell and Adam M. Bauer
Abstract
Introduction
I. Background
II. Approaches to the Study of Structural Variation
III. Variation as an Observable Phenomenon
A. Variation and Taxonomic Utility
B. Variation Associated with Developmental Plasticity
C. Geographically-based Variation
IV. In Situ Correlational Studies of the Relationship between Structural Variation and Functional Attributes
A. Trophic Polymorphism and Environmental Fluctuation
B. Clinical Variation
C. Microgeographic Variation
V. Ex Situ Studies of the Relationship between Structural Variation and Performance
A. Variation in Trophic Performance
B. Locomotor Performance
C. Fluctuating Asymmetry and Variation in Performance
D. Selection Experiments and the Investigation of the Limits of Variability
E. Other Measures of Structural and Functional Variation
V. Concluding Remarks
CHAPTER 18. A Universal Generative Tendency Toward Increased Organismal Complexity, by D. McShea
Introduction
I. Internal Variance as Complexity
II. Three Simple Models
III. The Effect of Increased Dimensionality
IV. Apparent Difficulties
V. Is there an Upward Bias in Real Lineages?
VI. If so, the Principle is Supported
VII. If not, Why not?
VIII. Testing the Principle
IX. A Reversal of Intuition
CHAPTER 19. Variation and Versatility in Macroevolution, by V. Louise Roth
I. Principles
A. To Vary is Easy
B. Evolvability and Versatility
II. Examples
A. Elephantid Teeth
B. Disparity and Versatility in Sciurdae
III. Overview and Conclusion
CHAPTER 20. Variation and Developmental Biology: Prospects for the Future, by David M. Parichy
Introduction
I. Model Organisms: Expanding the Fold
II. Ecologically Significant Differences in Form Between Species
III. How many ways to make a Phenotype: Developmental Variation and Morphological Similarity
IV. Intraspecific Developmental Variation: Canalization, and Developmental Plasticity
V. Conclusions
CHAPTER 21. Phenogenetics: Genotypes, Phenotypes, and Variation, by Samuel Sholtis and Kenneth Weiss
Introduction
I. Mechanism versus Variation
II. From Genotype to Phenotype: Mechanism
A. A quick digression concerning DNA sequence: arbitrary and saturated
B. Pre-transcriptional mechanisms
C. Post-transcriptional mechanisms
III. From Genotype to Phenotype: Variation
A. A lexicographer’s nightmare: Canalization, Robustness, Plasticity, Polyphenism…
B. Developmental process: patterning repeated traits
C. Gene regulation and the evolution of phenotypes
D. Phenogenetic drift: the role of chance in the evolution of genotype-phenotype relationships
IV. Summary
CHAPTER 22. The Study of Phenotypic Variability, by Benedikt Hallgrímsson and Brian K. Hall
Introduction
I. Variability and the Biological Hierarchy
II. Components of Variability
III. Current Approaches to Understanding the Development-Genetic Architecture of Variability
A. Pattern Based Approaches
B. Perturbation Based Approaches
C. Model Driven Approaches
IV. A Developmental Systems Approach to Phenotypic Variability
A. The Regulation of Form in the Mouse Mandible
B. The Regulation of Outgrowth of the Maxillary Process
V. Conclusion
Index