This volume gives a status report on the scientific investigations which can be undertaken in the field of exobiology using instruments in Earth orbit. A brief list of these recommended experiments is given here. Those listed for the Observational Exobiology section are in order of decreasing priority as determined by a consensus of the Workshop members. Otherwise, no priorities are implied by the order in which the experiments are listed. Observational Exobiology: 1. Search for extrasolar planetary systems, 2. Study star-forming regions in the galaxy--analogs for the solar nebula, 3. Study comets, asteroids, Titan, and the giant planets in our own solar system, 4. Study the organic chemistry of interstellar molecular clouds. Cosmic Dust Collection: 1. Develop and implement capture techniques which preserve biogenic material, 2. Develop and implement techniques to determine the orbits of dust particles, 3. Refine laboratory methods for the analysis of small particles. In Situ Experiments: 1. Study the formation, condensation, aggregation, and surface chemistry of suspended dust grains, 2. Create, release, and monitor an artificial comet in space, 3. Determine the viability of microorganisms in space.

Driving evolution forward, the Earth's physical environment has challenged the very survival of organisms and ecosystems throughout the ages. With a fresh new perspective, Evolution on Planet Earth shows how these physical realities and hurdles shaped the primary phases of life on the planet. The book's thorough coverage also includes chapters on more proximate factors and paleoenvironmental events that influenced the diversity of life. A team of notable ecologists, evolutionary biologists, and paleontologists join forces to describe drifting continents, extinction events, and climate change -- important topics that continue to shape Earth's inhabitants to this very day. In a world where global change has become an international issue, this book provides a several billion-year evolutionary perspective on what the environment and environmental change means to life.* Provides thorough background information on each topic while introducing cutting-edge research* Features original material solicited from the leading minds in evolutionary biology and geology today* Emphasizes the influence of massive geological forces - continental drift, volcanic activity, sea and tides

Life Science studies in space were initially driven by the need to explore how man could survive spaceflight conditions; the effects of being launched un der high accelerations, exposed to weightlessness and radiation for different periods of time, and returned to Earth in safety. In order to substantiate the detailed knowledge of potentially adverse effects, many model experiments were launched using organisms which ranged from bacteria, plants, inverte brates, rodents and primates through to man. Although no immediate life threatening effects were found, these experiments can be considered today as the precursors to life science research in space. Many unexplained effects on these life forms were attributed to the condition of weightlessness. Most of them were poorly recorded, poorly published, or left simply with anecdotal information. Only with the advent of Skylab, and later Spacelab, did the idea emerge, and indeed the infrastructure permit, weightlessness to be considered as an ex tended tool for research into some fundamental mechanisms or processes as sociated with the effect of gravity on organisms at all levels. The initial hy pothesis to extrapolate from hypergravity through 1 x g to near 0 x g effects could no longer be retained, since many of the experiment results were seen to contradict the models or theories in the current textbooks of biology and physiology. The past decade has been dedicated primarily to exploratory research.

This book aims at providing a brief but broad overview of biosignatures. The topics addressed range from prebiotic signatures in extraterrestrial materials to the signatures characterising extant life as well as fossilised life, biosignatures related to space, and space flight instrumentation to detect biosignatures either in situ or from orbit. The book ends with philosophical reflections on the implications of life elsewhere. In the 15 chapters written by an interdisciplinary team of experts, it provides both detailed explanations on the nature of biosignatures as well as useful case studies showing how they are used and identified in ancient rocks, for example. One case study addresses the controversial finding of traces of fossil life in a meteorite from Mars. The book will be of interest not only to astrobiologists but also to terrestrial paleontologists as well as any reader interested in the prospects of finding a second example of life on another planet.