Contents

Preface ix
The contributors xi

* Indicates Dr. Burr has a copy of this chapter.

PART I: GENERAL CHARACTERISTICS

*1. Evolution of visual behaviour 3
J.N. Lythgoe
Introduction 3
Evolution of eye structure 3
Physical and physiological constraints 5
Co-evolution 12

*2. Origin of invertebrate and vertebrate eyes 15
J. R. Cronly-Dillon
Introduction 15
Morphological characteristics of animal photoreceptor organs 19
Vertebrates evolved from a nemertine-like ancestor 29
Origin of pineal and parietal eyes 31
Cephalic organ 35
Origin of the vertebrate lens 44
Evolution of decussation of the vertebrate visual pathway 46
Concluding remarks 48

*3. Origins of eyes - with speculation on scanning eyes 52
R. L. Gregory
Introduction 52
Eye and brain: a hen-and-egg problem 53
Simple and compound eyes 55
Scanning eyes 55


PART II: EVOLUTIONARY DEVELOPMENTS

*4. The evolution of vertebrate visual pigments and photoreceptors 63
J.K. Bowmaker
Introduction 63
Visual pigments 64
Photoreceptors 65
Evolution of photoreceptors and visual pigments 66
Conclusions 78

5. The vertebrate dioptric apparatus 82
W.N. Charman
Introduction 82
Basic optics 82
Physical constraints on optical design 86
Limits on optical image quality at the retina g-)
Overall retinal image quality 99
Retinal aspects 100
Depth-of-focus, ametropia and accommodation 104
Conclusion 112

*6. Optics of the eyes of the animal kingdom 118
M.F. Land
Introduction 118
Camera eyes with corneal lenses 119
Aquatic lens eyes 121
Multi-element lenses 122
Concave mirror optics 123
Biological mirrors 126
Compound eves 127
Apposition optics 127
Superposition optics 128
Conclusions 133

7. Considering the evolution of vertebrate neural retina 136
I. Thompson
Introduction 136
Photoreceptors 137
Between the plexiform layers 139
Retinal ganglion cells 141
General observations 147

8. Functions of subcortical visual systems in vertebrates and the evolution of higher visual mechanisms 152
D. J. Ingle
Introduction 152
Visuomotor systems in amphibia 153
Modulation of tectal functions by satellite visual structures 157
Comparisons of motion sensitivity between fish and mammals 160
Shape recognition in vertebrates: advantages of a visual cortex 162

9. Neural control of pursuit eye movements 165
R. Eckmiller
Introduction 165
Sensory inputs for smooth pursuit system 167
Possible role of cerebral cortex in smooth pursuit control 174
Neural activity in the cerebellum and brain stem 180
Missing links and model considerations 189
Conclusions 191

10. Patterns of function and evolution in the arthropod optic lobe 203
D. Osorio
Introduction 203
Organization of visual processing 204
Evolution 212

*11. Evolution of visual processing 229
G.A. Horridge
Introduction 229
The laws of optics govern eye evolution 230
The evolution of vision 237
Insect vision 240
The evolutionary approach 241
The template model 243
Other models 251
Two-dimensional vision 233
Semi-vision performance 254
Larger templates 260
Whole-eye templates 263
Beyond semivision 267
Conclusion 268

12. Evolution of binocular vision 271
J. D. Pettigrew
Introduction 271
Hallmarks of binocular vision 271
Cats, owls, monkeys and machines 276
Evolution of avian stereopsis 280
Stereopsis in other vertebrate groups? 281

*13. Evolution of colour vision 284
C. Neumeyer
Introduction 284
Ability to discriminate wavelengths 285
Dimensionality of colour vision 289
Phylogeny of colour vision 295
Comparative colour perception 297
The question "Why" 298

*14. Uses and evolutionary origins of primate colour vision 306
J. D. Mollon
Introduction 306
Advantages of colour vision 306
Trichromacy and its evolution 310
Polymorphism of colour vision in platyrrhine primates 314

PART Ill: PHYLOGENETIC EVOLUTION OF THE EYE AND VISUAL SYSTENI

15. Photosensory systems in eukaryotic algae 323
J. D. Dodge
Introduction 323
Description of the eyespots and associated structures 323
Function of the photosensory apparatus 334
Evolution of the photosensory apparatus 336

16. Evolution of the cellular organization of the arthropod compound eye and optic lobe 341
I.A. Meinertzhagen
Introduction 341
The compound eye 342
Evolution of the ommatidium 344
The optic lobe 333
Conclusions 360

17. Photoreception and vision in molluscs 364
J. B. Messenger 364
Introduction 364
Classification 364
Extra-ocular photoreception 368
Non-cephalic eyes 371
Cephalic eyes 383
Visual processing 391
Summary

18. Evolution of vision in fishes 398
S. M. Bunt 398
Introduction 398
Constraints on evolution 399
Deuterostomes 401
Agnatha 405
The transition from the agnathan to the gnathostome 407
The aquatic visual environment 417
Conclusions

19. Central visual pathways in reptiles and birds: evolution of the visual system 421
T. Shimizu and H. J. Karten
Introduction 421
Phylogeny: reptiles, birds and mammals 421
Basic Sauropsida plan (reptiles and birds) 423
Reptilian plan 426
Avian plan 429
Evolution of the visual system 435
Conclusion 436

20. Evolution of mammalian visual pathways 442
G. H. Henry and T. R. Vidyasagar
Introduction 442
Mammalian characteristics in the primary visual pathway 442
Comparative view of features of the visual pathway 444
Conclusions 459

Appendix. Mammals 467
G. L. Walls
Introduction 467
Monotremes and marsupials 467
Placentals 472
Tentative schema of the evolution of the visual cells in vertebrates 480

Index 483