Environmental physiology and comparative biochemistry are shifting to a new level of focus-the gene. New developments in molecular biology have put simplified techniques for screening and analysis of gene expression into the hands of physiologists and biochemists who are using these for novel explorations of organismal responses to environmental stress. Selected topics cover both animal and plant systems to focus on recent advances in gene expression responses to environmental stresses including low and high temperature, freezing, oxygen limitation, reactive oxygen species, nutrient restriction as well as environmentally-cued programmed cell death. The book highlights the latest techniques and approaches for exploring the regulation of gene expression and illustrates, in selected systems, the interactions between genes and environmental stress that underlie adaptive responses.