Handbook of the Birds of the World – Volume 4

The book begins with a Foreword by Jürgen H. Haffer, titled Species Concepts and Species Limits in Ornithology.
The volume describes 6 families, fewer than other volumes, but contains the most species (834 species), as some of the families are very large; pigeons and doves (309 species), parrots (322 species) and cuckoos (136 species). These families are of interest to any ornithologist as they are present on all continents. Moreover, we find the sandgrouse, native to the arid terrains of Africa, southern Europe and south western Asia, the cockatoos, relatives of parrots, present in south-east Asia and Australia, and the turacos, inhabitants of sub-Saharan Africa. The plates and photographs in this volume show some of the most varied and colourful of the world’s birds.