Walter Koenig is Research Zoologist at the Museum of Vertebrate Zoology, University of California, Berkeley, and Adjunct Professor at the Department of Integrative Biology. Janis Dickinson is Assistant Research Zoologist at the Museum of Vertebrate Zoology, University of California, Berkeley.

• Introduction Walter D. Koenig and Janis L. Dickinson; 1. Evolutionary origins J. David Ligon and D. Brent Burt; 2. Delayed dispersal Jan Ekman, Janis L. Dickinson, Ben J. Hatchwell and Michael Griesser; 3. Fitness consequences of helping Janis L. Dickinson and Ben J. Hatchwell; 4. Parental care, load-lightening and costs Robert G. Heinsohn; 5. Matings systems and sexual conflict Andrew Cockburn; 6. Sex-ratio manipulation Jan Komdeur; 7. Physiological ecology Morné Du Plessis; 8. Endocrinology Steven J. Schoech, S. James Reynolds and Raoul K. Boughton; 9. Incest and incest avoidance Walter D. Koenig and Joseph Haydock; 10. Reproductive skew Robert D. Magrath, Rufus A. Johnstone and Robert G. Heinsohn; 11. Joint-laying systems Sandra L. Vehrencamp and James S. Quinn; 12. Conservation biology Jeffrey R. Walters, Caren B. Cooper, Susan J. Daniels, Gilberto Pasinelli and Karen Schiegg; 13. Mammalian contrasts and comparisons Andrew F. Russell; Summary Steven J. Pruett-Jones; Names of bird and mammal species mentioned in the text; References; Index.

"Recommended. Well-informed." S.W. Harris, emeritus, Humboldt State University, CHOICE

Walter Koenig is Research Zoologist at the Museum of Vertebrate Zoology, University of California, Berkeley, and Adjunct Professor at the Department of Integrative Biology. Janis Dickinson is Assistant Research Zoologist at the Museum of Vertebrate Zoology, University of California, Berkeley.

• Introduction Walter D. Koenig and Janis L. Dickinson; 1. Evolutionary origins J. David Ligon and D. Brent Burt; 2. Delayed dispersal Jan Ekman, Janis L. Dickinson, Ben J. Hatchwell and Michael Griesser; 3. Fitness consequences of helping Janis L. Dickinson and Ben J. Hatchwell; 4. Parental care, load-lightening and costs Robert G. Heinsohn; 5. Matings systems and sexual conflict Andrew Cockburn; 6. Sex-ratio manipulation Jan Komdeur; 7. Physiological ecology Morné Du Plessis; 8. Endocrinology Steven J. Schoech, S. James Reynolds and Raoul K. Boughton; 9. Incest and incest avoidance Walter D. Koenig and Joseph Haydock; 10. Reproductive skew Robert D. Magrath, Rufus A. Johnstone and Robert G. Heinsohn; 11. Joint-laying systems Sandra L. Vehrencamp and James S. Quinn; 12. Conservation biology Jeffrey R. Walters, Caren B. Cooper, Susan J. Daniels, Gilberto Pasinelli and Karen Schiegg; 13. Mammalian contrasts and comparisons Andrew F. Russell; Summary Steven J. Pruett-Jones; Names of bird and mammal species mentioned in the text; References; Index.

"Recommended. Well-informed." S.W. Harris, emeritus, Humboldt State University, CHOICE

Walter Koenig is Research Zoologist at the Museum of Vertebrate Zoology, University of California, Berkeley, and Adjunct Professor at the Department of Integrative Biology. Janis Dickinson is Assistant Research Zoologist at the Museum of Vertebrate Zoology, University of California, Berkeley.

• Introduction Walter D. Koenig and Janis L. Dickinson; 1. Evolutionary origins J. David Ligon and D. Brent Burt; 2. Delayed dispersal Jan Ekman, Janis L. Dickinson, Ben J. Hatchwell and Michael Griesser; 3. Fitness consequences of helping Janis L. Dickinson and Ben J. Hatchwell; 4. Parental care, load-lightening and costs Robert G. Heinsohn; 5. Matings systems and sexual conflict Andrew Cockburn; 6. Sex-ratio manipulation Jan Komdeur; 7. Physiological ecology Morné Du Plessis; 8. Endocrinology Steven J. Schoech, S. James Reynolds and Raoul K. Boughton; 9. Incest and incest avoidance Walter D. Koenig and Joseph Haydock; 10. Reproductive skew Robert D. Magrath, Rufus A. Johnstone and Robert G. Heinsohn; 11. Joint-laying systems Sandra L. Vehrencamp and James S. Quinn; 12. Conservation biology Jeffrey R. Walters, Caren B. Cooper, Susan J. Daniels, Gilberto Pasinelli and Karen Schiegg; 13. Mammalian contrasts and comparisons Andrew F. Russell; Summary Steven J. Pruett-Jones; Names of bird and mammal species mentioned in the text; References; Index.

"Recommended. Well-informed." S.W. Harris, emeritus, Humboldt State University, CHOICE