Harry Baker and Rosalind Ridley have done an admirable job in assem bling this collection of articles that describe the methodology frequently used to study a group of CNS illnesses often referred to as the "prion diseases." Research on prions and the disorders that they cause has progressed relatively rapidly over the last decade since the discovery of the prion protein (PrP) that allowed the application of modem molecular biological and genetic tools. The power of these techniques is awesome and their use in deciphering the once mysterious prion diseases has brought a wealth of new information. Although prions are unprecedented pathogens, appearing to consist only of PrPSc molecules, the diseases that they cause are no less remarkable. The prion diseases in animals include scrapie of sheep and goats as well as "mad cow" disease or bovine spongiform encephalopathy (BSE). In the United King dom, the epidemic of BSE has heightened public awareness of this previously obscure group of diseases such that any work in the field is likely to stir up interest in the media and become a subject of public debate. It has been diffi cult for British investigators to work on prion diseases without being involved in these controversies. As such, several chapters have been included that deal with political and social issues surrounding prion diseases. The human prion diseases present an equally fascinating saga in which these CNS degenerations present as genetic, sporadic, and infectious illnesses."

Harry Baker and Rosalind Ridley have done an admirable job in assem bling this collection of articles that describe the methodology frequently used to study a group of CNS illnesses often referred to as the "prion diseases." Research on prions and the disorders that they cause has progressed relatively rapidly over the last decade since the discovery of the prion protein (PrP) that allowed the application of modem molecular biological and genetic tools. The power of these techniques is awesome and their use in deciphering the once mysterious prion diseases has brought a wealth of new information. Although prions are unprecedented pathogens, appearing to consist only of PrPSc molecules, the diseases that they cause are no less remarkable. The prion diseases in animals include scrapie of sheep and goats as well as "mad cow" disease or bovine spongiform encephalopathy (BSE). In the United King dom, the epidemic of BSE has heightened public awareness of this previously obscure group of diseases such that any work in the field is likely to stir up interest in the media and become a subject of public debate. It has been diffi cult for British investigators to work on prion diseases without being involved in these controversies. As such, several chapters have been included that deal with political and social issues surrounding prion diseases. The human prion diseases present an equally fascinating saga in which these CNS degenerations present as genetic, sporadic, and infectious illnesses.

Mark Ridley's Evolution has become the premier undergraduate text in the study of evolution. Readable and stimulating, yet well-balanced and in-depth, this text tells the story of evolution, from the history of the study to the most revent developments in evolutionary theory.

The third edition of this successful textbook features updates and extensive new coverage. The sections on adaptation and diversity have been reorganized for improved clarity and flow, and a completely updated section on the evolution of sex and the inclusion of more plant examples have all helped to shape this new edition. Evolution also features strong, balanced coverage of population genetics, and scores of new applied plant and animal examples make this edition even more accessible and engaging.

• Dedicated website – provides an interactive experience of the book, with illustrations downloadable to PowerPoint, and a full supplemental package complementing the book – www.blackwellpublishing.com/ridley.
• Margin icons – indicate where there is relevant information included in the dedicated website.
• Two new chapters – one on evolutionary genomics and one on evolution and development bring state-of-the-art information to the coverage of evolutionary study.
• Two kinds of boxes – one featuring practical applications and the other related information, supply added depth without interrupting the flow of the text.
• Margin comments – paraphrase and highlight key concepts.
• Study and review questions – help students review their understanding at the end of each chapter, while new challenge questions prompt students to synthesize the chapter concepts to reinforce the learning at a deeper level.