1. Introduction: why Macroecology? Tim M. Blackburn and Kevin J. Gaston; Part I. Why Are Some Taxa More Diverse Than Others?: 2. Evolutionary analysis of species richness patterns in aquatic beetles: why macroecology needs a historical perspective Alfried P. Vogler and Ignacio Ribera; 3. The unified phenomenological theory of biodiversity Sean Nee; Part II. Why Are Most Species Rare?: 4. The neutral theory of biodiversity and biogeography, and beyond Stephen P. Hubbell and Jeffrey Lake; 5. Breaking the stick in space: of niche models, metacommunities and patterns in the relative abundance of species Pablo A. Marquet, Juan E. Keymer and Hernan Cofre; Part III. Why Are There More Species in the Tropics?: 6. How to reject the area hypothesis of latitudinal gradients Michael L. Rosenzweig; 7. Climatic-energetic explanations of diversity: a macroscopic perspective Robert J. Whittaker, Katherine J. Willis and Richard Field; 8. The importance of historical processes in global patterns of diversity Andrew Clarke and J. Alistair Crame; Part IV. Why are More Species Small-Bodied?: 9. Why are most species small-bodied? A phylogenetic view Andy Purvis, C. David L. Orme and Konrad Dolphin; 10. Adaptive diversification of body size: the roles of physical constraint, energetics and natural selection Brian A. Maurer; Part V. Why are some species more likely to go extinct?: 11. Life histories and extinction risk John D. Reynolds; 12. Routes to extinction Bernt-Erik Saether and Steinar Engen; Part VI. Why Aren't Species More Widely Distributed?: 13. Why aren't species more widely distributed? Physiological and environmental limits F. Ian Woodward and C. K. Kelly; 14. Macroecology and microecology: linking large-scale patterns of abundance to population processes Andrew R. Watkinson, Jennifer A. Gill and Robert P. Freckleton; 15. Genetics and the boundaries of species' distributions R. K. Butlin, J. R. Bridle and M. Kawata; Part VII. Why Are There Interspecific Allometries?: 16. Intraspecific body size optimisation produces interspecific allometries J. Kozowski, M. Konarzewski and A. T. Gawelczyk; 17. Scaling the macroecological, and evolutionary implications of size and metabolism within and across plant taxa Brian J. Enquist; Part VIII. Why is Macroecology Important?: 18. Macroecology and conservation biology Kevin J. Gaston and Tim M. Blackburn; 19. Evolutionary macroecology and the fossil record David Jablonski, Kaustuv Roy and James W. Valentine; 20. Comparative methods for adaptive radiations Robert P. Freckleton, M. Pagel and Paul H. Harvey; 21. The next step in macroecology: from general empirical patterns to universal ecological laws James H. Brown, James F. Gillooly, Geoffrey B. West and Van M. Savage.