Most natural populations intermittently experience extremely stressful conditions. This book discusses how such conditions can cause periods of intense selection, increasing both phenotypic and genetic variation, and allowing organisms with novel characteristics to be first generated and then established in the population. The authors argue that stressful conditions can have a major impact on the environment, backing up their arguments with evidence from the fossil record. They suggest further that, as a consequence, periods of stress must be taken into consideration when long term conservation strategies are planned, particularly as stressful conditions are becoming increasingly prevalent as a result of human activities. This broad overview will be of great interest to students and researchers in the field of evolutionary biology, genetics, ecology, palaeontology and conservation biology.
The hominin fossil record documents a history of critical evolutionary events that have ultimately shaped and defined what it means to be human, including the origins of bipedalism; the emergence of our genus Homo; the first use of stone tools; increases in brain size; and the emergence of Homo sapiens, tools, and culture. The Earth's geological record suggests that some evolutionary events were coincident with substantial changes in African and Eurasian climate, raising the possibility that critical junctures in human evolution and behavioral development may have been affected by the environmental characteristics of the areas where hominins evolved. Understanding Climate's Change on Human Evolution explores the opportunities of using scientific research to improve our understanding of how climate may have helped shape our species. Improved climate records for specific regions will be required before it is possible to evaluate how critical resources for hominins, especially water and vegetation, would have been distributed on the landscape during key intervals of hominin history. Existing records contain substantial temporal gaps. The book's initiatives are presented in two major research themes: first, determining the impacts of climate change and climate variability on human evolution and dispersal; and second, integrating climate modeling, environmental records, and biotic responses. Understanding Climate's Change on Human Evolution suggests a new scientific program for international climate and human evolution studies that involve an exploration initiative to locate new fossil sites and to broaden the geographic and temporal sampling of the fossil and archeological record; a comprehensive and integrative scientific drilling program in lakes, lake bed outcrops, and ocean basins surrounding the regions where hominins evolved and a major investment in climate modeling experiments for key time intervals and regions that are critical to understanding human evolution.
Today's microorganisms represent the vast majority of biodiversity on Earth and have survived nearly 4 billion years of evolutionary change. However, we still know little about the processes of evolution as applied to microorganisms and microbial populations. Microbial evolution occurred and continues to take place in a vast variety of environmental conditions that range from anoxic to oxic, from hot to cold, from free-living to symbiotic, etc. Some of these physicochemical conditions are considered "extreme", particularly when inhabitants are limited to microorganisms. It is easy to imagine that microbial life in extreme environments is somehow more constrained and perhaps subjected to different evolutionary pressures. But what do we actually know about microbial evolution under extreme conditions and how can we apply that knowledge to other conditions? Appealingly, extreme environments with their relatively limited numbers of inhabitants can serve as good model systems for the study of evolutionary processes. A look at the microbial inhabitants of today's extreme environments provides a snapshot in time of evolution and adaptation to extreme conditions. These adaptations manifest at different levels from established communities and species to genome content and changes in specific genes that result in altered function or gene expression. But as a recent (2011) report from the American Academy of Microbiology observes: "A complex issue in the study of microbial evolution is unraveling the process of evolution from that of adaptation. In many cases, microbes have the capacity to adapt to various environmental changes by changing gene expression or community composition as opposed to having to evolve entirely new capabilities." We have learned much about how microbes are adapted to extreme conditions but relatively little is known about these adaptations evolved. How did the different processes of evolution such as mutation, immigration, horizontal (lateral) gene transfer, recombination, hybridization, genetic drift, fixation, positive and negative selection, and selective screens contribute to the evolution of these genes, genomes, microbial species, communities, and functions? What are typical rates of these processes? How prevalent are each of these processes under different conditions? This book explores the current state of knowledge about microbial evolution under extreme conditions and addresses the following questions: What is known about the processes of microbial evolution (mechanisms, rates, etc.) under extreme conditions? Can this knowledge be applied to other systems and what is the broader relevance? What remains unknown and requires future research? These questions will be addressed from several perspectives including different extreme environments, specific organisms, and specific evolutionary processes.
Climate Change: Evidence and Causes is a jointly produced publication of The US National Academy of Sciences and The Royal Society. Written by a UK-US team of leading climate scientists and reviewed by climate scientists and others, the publication is intended as a brief, readable reference document for decision makers, policy makers, educators, and other individuals seeking authoritative information on the some of the questions that continue to be asked. Climate Change makes clear what is well-established and where understanding is still developing. It echoes and builds upon the long history of climate-related work from both national academies, as well as on the newest climate-change assessment from the United Nations' Intergovernmental Panel on Climate Change. It touches on current areas of active debate and ongoing research, such as the link between ocean heat content and the rate of warming.
This book summarizes the key adaptations enabling extremophile fishes to survive under harsh environmental conditions. It reviews the most recent research on acidic, Antarctic, cave, desert, hypersaline, hypoxic, temporary, and fast-flowing habitats, as well as naturally and anthropogenically toxic waters, while pointing out generalities that are evident across different study systems. Knowledge of the different adaptations that allow fish to cope with stressful environmental conditions furthers our understanding of basic physiological, ecological, and evolutionary principles. In several cases, evidence is provided for how the adaptation to extreme environments promotes the emergence of new species. Furthermore, a link is made to conservation biology, and how human activities have exacerbated existing extreme environments and created new ones. The book concludes with a discussion of major open questions in our understanding of the ecology and evolution of life in extreme environments.
Most organisms and populations have to cope with hostile environments, threatening their existence. Their ability to respond phenotypically and genetically to these challenges and to evolve adaptive mechanisms is, therefore, crucial. The contributions to this book aim at understanding, from a evolutionary perspective, the impact of stress on biological systems. Scientists, applying different approaches spanning from the molecular and the protein level to individuals, populations and ecosystems, explore how organisms adapt to extreme environments, how stress changes genetic structure and affects life histories, how organisms cope with thermal stress through acclimation, and how environmental and genetic stress induce fluctuating asymmetry, shape selection pressure and cause extinction of populations. Finally, it discusses the role of stress in evolutionary change, from stress induced mutations and selection to speciation and evolution at the geological time scale. The book contains reviews and novel scientific results on the subject. It will be of interest to both researchers and graduate students and may serve as a text for graduate courses.
In recent years, scientists have realized that evolution can occur on timescales much shorter than the 'long lapse of ages' emphasized by Darwin - in fact, evolutionary change is occurring all around us all the time. This work provides an authoritative and accessible introduction to eco-evolutionary dynamics, a cutting-edge new field that seeks to unify evolution and ecology into a common conceptual framework focusing on rapid and dynamic environmental and evolutionary change.
Human-induced environmental change currently represents the single greatest threat to global biodiversity. Species are typically adapted to the local environmental conditions in which they have evolved. Changes in environmental conditions initially influence behaviour, which in turn affects species interactions, population dynamics, evolutionary processes and, ultimately, biodiversity. How animals respond to changed conditions, and how this influences population viability, is an area of growing research interest. Yet, despite the vital links between environmental change, behaviour, and population dynamics, surprisingly little has been done to bridge these areas of research. Behavioural Responses to a Changing World is the first book of its kind devoted to understanding behavioural responses to environmental change. The volume is comprehensive in scope, discussing impacts on both the mechanisms underlying behavioural processes, as well as the longer-term ecological and evolutionary consequences. Drawing on international experts from across the globe, the book covers topics as diverse as endocrine disruption, learning, reproduction, migration, species interactions, and evolutionary rescue.
This book focuses on how climate affects or affected the biosphere and vice versa both in the present and in the past. The chapters describe how ecosystems from the Antarctic and Arctic, and from other latitudes, respond to global climate change. The papers highlight plant responses to atmospheric CO2 increase, to global warming and to increased ultraviolet-B radiation as a result of stratospheric ozone depletion.
This open access book describes the serious threat of invasive species to native ecosystems. Invasive species have caused and will continue to cause enormous ecological and economic damage with ever increasing world trade. This multi-disciplinary book, written by over 100 national experts, presents the latest research on a wide range of natural science and social science fields that explore the ecology, impacts, and practical tools for management of invasive species. It covers species of all taxonomic groups from insects and pathogens, to plants, vertebrates, and aquatic organisms that impact a diversity of habitats in forests, rangelands and grasslands of the United States. It is well-illustrated, provides summaries of the most important invasive species and issues impacting all regions of the country, and includes a comprehensive primary reference list for each topic. This scientific synthesis provides the cultural, economic, scientific and social context for addressing environmental challenges posed by invasive species and will be a valuable resource for scholars, policy makers, natural resource managers and practitioners.
