Scientific American Library series ;

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At first glance, plants appear to be extremely passive organisms, silent, immobile, and unprotected. But within their placid exteriors there occurs a continuous swirl of activity - a complex orchestration of processes that allow the plant to obtain food, endure drastic weather, fend off predators, anticipate the future, and carry out tasks more often associated with higher animals. Plants are organic chemists par excellence, capable of synthesizing complex molecules; and they are experts at survival, equipped to withstand and adapt to the many challenges of nature. In Life Processes of Plants, botanist Arthur Galston describes how plants live, react to crises, and change when necessary. It is an eloquent and exquisitely illustrated volume, vividly conveying the scientific research that brought these extraordinary natural skills to light. Galston explores the dynamic existence of plants at all levels - from the organism as a whole down to the interplay of its tissues, cells, and molecules. Readers will be intrigued by the plant's methods of storing energy from sunlight, by the internal clock that tells plants the time of day, by the chemical warfare used against predators and competitors, and by the hormonal and electro-chemical communications network that conveys information within the plant. In addition, readers will witness the plant's impressive powers of regeneration, wherein almost any single cell can be the starting point for a complete separate plant. Another chapter shows how this regenerative ability and cooperation with microbes are the keys to remarkable developments in the exciting field of agricultural biotechnology . Life Processes of Plants illuminates some often overlooked phenomena of the natural world. Readers will see plants in a whole new way - as fascinating examples of both the complexity and simplicity of life.

An accessible question-and-answer guides to common sleep problems. Provide practical guidance about the various self-help measures, conventional medical options and complementary therapies. Written in clear, jargon-free language and conforming to a series format.

Where and when did modern humans (Homo sapiens) first appear? Who were our immediate evolutionary ancestors? What features distinguish modern humans and how did these features arise? These questions have gripped the scientific community and the public since the mid-nineteenth century, when the discovery of Neanderthal Man and the publication of Darwin's Origin of Species rocked the foundations of long-held beliefs on the subject. Many new findings, speculations, and reevaluations have sharpened our views of modern human origins since then. Nevertheless, the controversy continues, as the patchy fossil record and new evidence derived from genetic techniques have given rise to competing theories. Are we the result of a single uninterrupted lineage, with each distinct species of human leading directly to the next? Or, do species such as the Neanderthal represent offshoots of an evolutionary tree that died out without leaving successors? Did modern humanity arise roughly contemporaneously in different parts of the world or from a single species in a single location? And how do biological, linguistic, artistic, and technological factors distinguish Homo sapiens from near and distant relatives? At stake in the argument is nothing less than the very definition of what it means, biologically and culturally, to be human. In this vividly written volume, award-winning science author Roger Lewin describes the discoveries, the intellectual clashes, and the often conflicting interpretations of evidence that have shaped the current debate on modern humanity's origin. Readers will learn of astonishing findings (the original Neanderthal bones, and provocative theories (the genetically-derived speculation that we are all the children of a single African female who lived about 200,000 years ago), as well as one preposterous hoax (the Piltdown Man). Readers will also see the evolution of the modern science of paleoanthropology, which brings molecular biology, genetics, population biology, linguistics, and other disciplines into the search for the distinctive stamp of Homo sapiens in artifacts and skeletal remains.