Contents

25 July 1997
Vol 277, Issue 5325

About The Cover

Humankind casts a large shadow over the whole planet, with the structure and function of virtually every ecosystem being affected by pervasive human activity. The special section beginning on 485 pulls together our current scientific understanding of the topic and examines science-led measures to optimize resource management and protect the environment. Also see the related Editorial on page 457. [Photo illustration: Tracy Keaton Drew]