Intro
Preface
Contents
Chapter 1: On Distributed Visual Systems
1.1 Introduction
1.2 From a Simple Light Sensor to a Sophisticated Eye
1.3 Sophisticated Vision Through a Distributed Visual System
1.4 Pros and Cons of Distributed Vision (Or "To Evolve a Centralized or Distributed Visual System")
1.5 Survey of Diverse Distributed Visual Systems
1.5.1 Cnidarians
1.5.2 Echinoderms (Deuterostomes)
1.5.3 Polychaetes (Annelida)
1.5.4 Bivalvia (Mollusks)
1.5.5 Chitons (Mollusks)
1.5.6 Myriapoda (Arthropoda)
1.5.7 Pancrustacea (Arthropoda)

1.5.8 Arachnida (Arthropoda)
1.6 Summary/Conclusions
References
Chapter 2: Cnidarians: Diversity and Evolution of Cnidarian Visual Systems
2.1 Introduction
2.2 Cnidarian Phylogenetic Relationships
2.3 Cnidarian Photobiology
2.3.1 Cnidarian Opsins
2.3.2 Cnidarian Phototransduction and the Origins of Metazoan Visual Cascades
2.3.3 Cnidarian Photoreceptor Neurons and Distributed Sensory Systems
2.3.4 Cnidarian Eyes
2.3.5 Distributed Visual Systems in Cnidarians
2.4 Photosensory Behaviors in Cnidarian Larvae
2.4.1 Anthozoan Larvae
2.4.2 Medusozoan Larvae

2.5 Photosensory Behaviors in Adult Cnidarians
2.5.1 Anthozoan Adults
2.5.2 Medusozoan Adults
2.6 Future Directions
References
Chapter 3: Extraocular Vision in Echinoderms
3.1 Introduction
3.2 A Brief History of Extraocular Photoreception and Vision in Echinoderms
3.3 Visual Behavior
3.3.1 Orientation to Static Stimuli
3.3.2 Shadows and Looms
3.4 Physiology
3.4.1 Sea Urchins
3.4.2 Brittle Stars
3.5 Photoreceptors
3.5.1 Molecular Characteristics
3.5.2 Sea Urchin Opsins
3.5.3 Brittle Star Opsins
3.5.4 Opsins Across Echinodermata

3.5.5 Retinal Determinant Genes and Transcription Factors
3.6 Achieving Spatial Resolution: Proposed Mechanisms
3.6.1 Screening
3.6.2 Limits of Resolution
3.6.3 Optics
3.7 Nervous Systems and Processing
3.8 Evolution of Extraocular Vision
3.9 Future Research and Challenges
References
Chapter 4: Dispersed Vision in Starfish: A Collection of Semi-independent Arms
4.1 Introduction
4.2 The Starfish Eyes
4.2.1 Low Pass Filtering in Starfish Eyes
4.2.2 Opsins and Spectral Sensitivity
4.3 Behavioral Repertoire of Starfish
4.4 Light Guided Behaviors

4.4.1 Shadow Response and Extraocular Photoreception
4.4.2 Visually Guided Habitat Detection: Proof of Image Forming Eyes
4.4.3 Eye Movements and Active Vision
4.4.4 Other Starfish Behaviors Putatively Involving Vision
4.5 Multimodal Control of Behavior
4.6 Processing of the Visual Information
4.6.1 Structure of the Starfish CNS
4.6.2 The Ectoneural Part of the RNC
4.6.3 Supporting Cells
4.6.4 Specializations in A. planci: Neural Bulbs on the RNC
4.7 Concluding Remarks
References
Chapter 5: Distributed Visual Systems in Pteriomorphian Bivalves