Deep Homology?

Half title......Page 2
Title page......Page 3
Imprints page......Page 4
Contents......Page 6
Preface......Page 8
Foreword......Page 17
Introduction......Page 23
1 Body Axes......Page 30
The anterior–posterior axis is subdivided by Hox genes......Page 31
otd/Otx may have ruled the front as caudal/Cdx ruled the rear......Page 46
Segmentation is so rare among phyla that it must be convergent......Page 48
The dorsal–ventral axis is established by BMP and Chordin......Page 53
Left–right asymmetry emerges from cytoskeletal chirality......Page 57
A common matrix of transcription factors subdivides the CNS......Page 70
Neurons make excessive connections that are later pruned......Page 78
Coordination between left and right involves commissural axons......Page 83
After an axon crosses the midline it can never go back again......Page 85
Neurites emanating from the same neuron repel one another......Page 89
A command center in the brain controls circadian rhythms......Page 92
Photons are detected by 11-cis-retinal (a vitamin-A derivative)......Page 101
Detection is facilitated by elaborate phospholipid membranes......Page 105
Color vision relies on a subclass of dedicated photoreceptors......Page 116
The paired-homeobox gene Pax6 governs eye development......Page 127
But other facts undermine Pax6's reputation as a master gene......Page 129
The hair cells of the human cochlea develop like fly bristles......Page 136
Macular hair cells display a plane of symmetry like the fly eye......Page 143
Is there a gene complex for human hair like the one for fly bristles?......Page 150
Flies use their antenna as an ear but still rely on conserved genes......Page 154
The acoustic properties of human and fly ears are quite similar......Page 158
Odors and flavors are identified via combinatorial compilation......Page 160
Gustatory neurons are broadly tuned to only a few taste qualia......Page 163
Olfactory neurons use one receptor and project to one glomerulus......Page 164
Successful glomerular wiring requires sensory neuron activity......Page 169
Pheromones are processed separately from other kinds of odors......Page 171
6 Limbs......Page 173
Appendages use a common set of genes to delineate their axes......Page 175
But the case for appendages in urbilaterians is not compelling......Page 181
Odd-skipped transcription factors are critical for joint formation......Page 182
Extra-joint syndromes are oddly correlated with polarity shifts......Page 185
Some vertebrate and arthropod taxa can regenerate their limbs......Page 188
The critical gene for specifying heart identity seems to be tinman......Page 190
But nematodes use tinman for a non-cardiac (pharyngeal) pump......Page 195
VEGF plays a regulatory role in circulatory system development......Page 196
Epilogue......Page 198
References......Page 200
Index......Page 424