Fishy tales of trilobites and elusive animals

When the definitive history of biology is written, the 1960s will probably be shown to be the period when the subject "grew up" and took its place alongside the "hard sciences". One of the developing areas was that of evolutionary ecology. While having its origins more than 100 years before, largely in behavioural studies, it (eventually) drew from all areas of biology and became a true synthesis of many, diverse fields. For the developing and inquiring mind it showed what biology really is - a multifaceted, integrated subject.

Evolutionary ecology was an exciting subject in the 1960s and Peter Mayhew, 40 years later, obviously enjoyed writing Discovering Evolutionary Ecology . As he admits on his university website: "I tried to make it short and fun to read too. Cheap, quick and informative; what have you got to lose?"

Mayhew tries and wholly succeeds in taking us on a journey from genes and chromosomes through inheritance and selection to population dynamics and adaptations, ending up with the birth and death of species and the "big evolution" (the species richness and diversity of clades) and "big ecology" (patterns of abundance, distribution and diversity).

As a book on evolutionary ecology, it is surprisingly free from mathematical equations (it contains just three) and this will encourage mathematically challenged undergraduates to read it. The touch is light and friendly, in many ways following in the tradition of all good books of natural history. On the downside, many of the photographs are muddy, although the trilobite is scarily like Mary the alien from an episode of Torchwood. The references more or less stop in 2004 and the glossary looks like an afterthought.

But these are minor quibbles about a book that is both readable and well-illustrated with relevant and easy-to-understand graphs, line drawings and tables. Undergraduates will love it - how many textbooks do you know that describe a large number as "whopping" or the diversity of the Great Lakes of East Africa as "surprisingly fishy"?

Ecology and evolution have traditionally been seen as complementary subjects, but epidemiology was once a science apart from the basic precepts of ecology, subsumed in the practice of medicine and veterinary science.

However, as Disease Ecology by Sharon Collinge and Chris Ray demonstrates, many (if not all) of the important infectious diseases emanate from complex ecological communities, some in altered states, and all with the potential to modify the prevalence of disease in hitherto unexpected ways. The maturation of community ecology and population dynamics have made this a natural advance in understanding, and this book is a timely statement of the areas of disease ecology where most progress is likely to be made in future.

For those less familiar with infectious diseases the book provides fascinating insights into their ecological context. In the introductory chapter, Collinge and Ray give a very decent overview of why the subject is exciting community ecologists, and the 13 separately authored chapters that follow provide a consistent approach. Rather than rushing on to find the good stuff in other chapters, this is worth digesting first. One of the devices that anchors each chapter is the use of boxes that "highlight key tools and concepts in community ecology", although these are of variable quality.

The study systems covered range from microbial community interactions within vectors to the geographic spread of rabies. Although only a few ecosystem types are included (how much is known of disease epidemiology in the oceans?), the lack of restriction on the taxa or habitats is welcome, as the reader finds parallels in the ecology of disease in woodland, salt marsh and freshwaters, or among plants and animals.

One recurring theme is the role of anthropogenic activities (for example, forest management, habitat fragmentation, urbanisation and agriculture) in the alteration of community dynamics and hence the amplification of disease. The authors hope to engage a broad readership. Scientists with an interest in other areas of community ecology will certainly be drawn to this book, as will undergraduates with some experience of ecological processes. None could fail to be impressed by the fact that oaks determine much of the interannual change in Lyme disease risk in northeast US or that management plans to minimise Nipah disease in Malaysia involve exclusion of fruit trees from buffer zones at pig farms.

The breadth of the book is bounded by the experience of an almost exclusively US authorship - though the case studies are global - but it would have had an extra frisson of excitement if it had drawn more effectively on expertise from other countries. No matter; there is plenty here to stimulate the interest equally of land managers and those with first-hand experience of disease, and we would recommend it to any ecology student.

Supporting apex predators can greatly benefit ecosystem-level conservation.

While Hans Kruuk's book is not principally about the conservation of otters (it is focused on their ecology) there is no doubt that the otter in the British Isles is a charismatic species that holds a special place in our natural fauna, and whose conservation greatly enhances broader aspects of biodiversity.

This book is neither exclusively science nor primarily natural history, but brings together the best of both worlds. Through Kruuk's exhaustive knowledge of otters he has made the science accessible to natural historians and provides a wealth of observations that scientists may otherwise overlook. Kruuk has spent much of his life researching these elusive creatures and his methods have often relied on painstaking and direct observation of otters in their natural environments.

Anyone who has tried this will testify to the almost Zen-like concentration required. As the author suggests: "Like many other types of fieldwork with animals, it is something of an art, of which the technical details have to be learned by practice".

For all their perkiness and mischievous demeanour, much loved by the makers of wildlife film documentaries, otters have had a hard time in their natural environments, and they embrace a lifestyle that is more risky than for most carnivores. Many of the chapters identify clearly why this is so, from the perspective of evolution and habitat and with an emphasis on the difficulty experienced by an otter of balancing its energy budget in a cold, wet environment.

This is a much more comprehensive book than anything that has gone before and deals with otter species worldwide. The species and their habitats are recognisably different but have remarkably similar ecologies, and the author explores these thematically throughout the book. This will be a mine of information for any scientist and a good read for anyone interested in mammals.

Interestingly, for a book on otters, the new pages of the paperback copy smelled worryingly of fish.

Keith Day is professor of environmental science, and Brian S. Rushton is reader in ecology and taxonomy, Ulster University.