Introduction The first bird I can remember having really noticed was a Common Pochard drake on a small lake. This was at the age of about six in North Wales, where I had the good fortune to be born and raised. The most recent, 62 years later, that had me leaping up from the desk to grab binoculars and run downstairs and into the garden, was an Osprey flying over the house where I now live, next to the bird-rich Exe Estuary in beautiful Devon. In between, birds have delighted, inspired and fascinated me on a daily basis. Although I consider myself an all-round naturalist, at least in my interest if not my detailed knowledge, birds have always held my main attention. It is true for many others too, not least zoologists, for birds have figured hugely in scientific research. Birds are so noticeable, since they are largely active by day and live virtually everywhere, we admire their mastery of flight or their beautiful plumage, and regard the songs and calls of many species as the most beautiful or remarkable of all natural sounds. As well as providing ornithologists such excellent subjects for research, they give delight to birders and all who love nature, and inspire writers, poets, artists and photographers.

Today, their importance as a crucial part of all ecosystems, and as indicators of the damage we are wreaking on their - and our - environment, is established beyond question, but is, regrettably, all too often unheeded by politicians and other decision makers. If, as well as providing information, this book helps the reader to feel passionate about the birds with which we share the world, and to do something to help them, then I will be doubly pleased. Since our earliest prehistoric encounters with these remarkable creatures, they have been deeply enmeshed in our collective consciousness, embedded in so many myths, proverbs and parts of speech. A world devoid of birds would be an immensely poorer place. No single work, even one of many volumes, can be comprehensive; ornithology is such a vast subject today, with so many advances in the last few decades alone. In this book my aim is to provide a succinct and accessible guide to many of the most important aspects of bird biology, combined with an account of everyone of the almost 200 families of birds alive today. The book is clearly structured, with two major sections. The first, embracing Chapters 1 to 9, begins at the beginning, with a chapter describing the evolution of birds, then leads on to chapters dealing in turn with bird anatomy, physiology, flight, food and feeding, social life and population biology, biogeography and habitat and migration.

It ends with an account of how we have interacted with birds, both negatively and positively, a theme that recurs in many of the pages in the second section. The information in the text is supported by over a thousand photographs, diagrams and maps. In addition, boxed text deals with a range of themes of particular interest. The second section, Chapter 10, is an account of everyone of the 32 orders and 195 families of birds. A few words about scientific classification are apposite here, for those unfamiliar with how it works. Whether applied to birds or to any other living organisms, it uses the same hierarchical arrangement of ranks. In all cases the scientific names are either in Latin or the Latinised form of words derived from Greek or other languages, often describing some distinctive feature or the place where the bird lives, or celebrating the name of a person. This means that unlike common names, which vary from one language to another, the scientific names are truly internationaL The basic unit of classification is the species.

This is given a binomial name consisting of two parts, as originally proposed in the 18th century by the Swedish naturalist Linnaeus. It is always printed in italics. The first part, always given an initial capital, is the generic name. This is the name of the genus -- the group of similar, closely related species to which the species belongs (in some cases a genus may contain only a Single particularly distinctive species). The second part, always in lower case type, is the specific name; although this may be the same for many species (for instance, alba , white, minor , smaller, or americana , from America) the combination of generic and specific names is unique. Similar genera of birds are gathered together into families, whose names end in -idae, similar families into orders, with names ending in -iformes. All the orders combined form the Class Aves, the birds. In addition to this basic scheme, species may be divided into subspecies, more informally called races, which are given a third name, or trinomiaL There are other, intermediate, rankings too, such as superfamilies and subclasses.

The two used most in this book are tribes (ending in -ini), and subfamilies (ending in -inae). Just as the birds have evolved since they first appeared more than 150 million years ago, and continue to evolve today, our classification system itself is subject to a process of evolution. In contrast to some other groups of animals, birds have not left a rich fossil record. Nevertheless, new fossils are being discovered, and through many other studies more data is being continually added. In addition, similar features that initially suggested relationships may turn out to be the result of convergent evolution, in which two unrelated groups have evolved similarities due to adopting similar lifestyles. Most profound in its effect on how birds are classified have been the revolutionary techniques of DNA analysis in the past couple of decades. This has led to often surprising reassessments of relationships, including the realisation that some species in a family may not belong there but are better placed in a different family. It also has an impact on whether a subspecies should be promoted to species rank or a species demoted to subspecies level, although there is a degree of subjectivity involved in such decisions between the classifiers known as ''lumpers'' and those dubbed ''splitters''.

Because taxonomists - the scientists who classify organisms - do not always agree about the interpretation of the data, there is no single definitive list of the world''s bird species or how they should be arranged into families, and families into orders. Although a consensus is emerging in many cases, in others there is still considerable disagreement about the wisdom of following some proposals. As a result, my policy in this book, reflecting that of the ornithologists in the Bird Group of the Natural History Museum, is to adopt a conservative approach, and (apart from a few exceptions) to follow the arrangement set out in the third edition of The Howard and Moore Complete Checklist of the Birds of the World (see Further Information, p. 589, for details). At the same time, I have frequently referred to major changes that have been accepted by many authorities and that are likely to stand the test of time. As for the common names of species, I have generally followed those used in Howard and Moore, third edition, but in a few cases I have used alternatives that I regarded as preferable. In this book, the common names always have initial capitals. I have also included the common names used in North America, where these differ from those we generally use in Britain.

The accounts in Chapter 10 dealing with the orders and families summarise their salient features and in many cases, also include brief mention of their relationships to other birds. The family accounts, which vary in length according to the size and diversity of the family, detail the appearance, behaviour and lifestyle of its members (or member in the case of families containing just a single species), and where appropriate, include a summary of distinct subgroups within it. Each family text has a box containing key facts under standardised headings. The species whose names are listed under ''Conservation'' are many of those identified by BirdLife International as experiencing various levels of threat. Spa.