Anthropogenic climate change has driven widespread changes in marine environments, including ocean warming, ocean acidification, and the formation of hypoxic zones. Such environmental changes would pose direct challenges to the survival and adaptation of aquatic organisms, greatly affecting the biodiversity of marine life and marine ecosystems. Changes in the marine environment are likely to have strong effects at the physiological, behavioral, and molecular levels, with implications at the individual, population, and species levels, resulting in the degradation of genetic resources through massive mortality. For example, the ingestion, digestion, respiration, and growth of aquatic animals were greatly depressed under extreme environments. In the long run, maintaining a sustainable ocean would require a better understanding of the adaptation of marine animals in response to the effects of multiple environmental stressors. The Research Topic is aimed to discuss the potential impacts of individual and compounded extreme environments on aquatic animals, as well as the regulatory mechanisms and adaptation strategies of marine species to cope with these impacts.

Biology of Stress in Fish: Fish Physiology provides a general understanding on the topic of stress biology, including most of the recent advances in the field. The book starts with a general discussion of stress, providing answers to issues such as its definition, the nature of the physiological stress response, and the factors that affect the stress response. It also considers the biotic and abiotic factors that cause variation in the stress response, how the stress response is generated and controlled, its effect on physiological and organismic function and performance, and applied assessment of stress, animal welfare, and stress as related to model species. - Provides the definitive reference on stress in fish as written by world-renowned experts in the field - Includes the most recent advances and up-to-date thinking about the causes of stress in fish, their implications, and how to minimize the negative effects - Considers the biotic and abiotic factors that cause variation in the stress response

Birds have and continue to fascinate scientists and the general public. While the avian respiratory system has unremittingly been investigated for nearly five centuries, important aspects on its biology remain cryptic and controversial. In this book, resolving some of the contentious issues, developmental-, structural- and functional aspects of the avian lung-air sac system are particularized: it endeavors to answer following fundamental questions on the biology of birds: how, when and why did birds become what they are? Flight is a unique form of locomotion. It considerably shaped the form and the essence of birds as animals. An exceptionally efficient respiratory system capacitated birds to procure the exceptionally large quantities of oxygen needed for powered (active) flight. Among the extant air-breathing vertebrates, comprising ~11,000 species, birds are the most species-rich-, numerically abundant- and extensively distributed animal taxon. After realizing volancy, they easily overcame geographical obstacles and extensively dispersed into various ecological niches where they underwent remarkable adaptive radiation. While the external morphology of birds is inconceivably uniform for such a considerably speciose taxon, contingent on among other attributes, lifestyle, habitat and phylogenetic level of development have foremost determined the novelties that are displayed by diverse species of birds. Here, critical synthesizes of the most recent findings with the historical ones, evolution and behavior and development, structure and function of the exceptionally elaborate respiratory system of birds are detailed. The prominence of modern birds as a taxon in the Animal Kingdom is underscored. The book should appeal to researchers who are interested in evolutionary processes and how adaptive specializations correlate with biological physiognomies and exigencies, comparative biologists who focus on how various animals have solved respiratory pressures, people who study respiration in birds and other animals and ornithologists who love and enjoy birds for what they are – profoundly interesting animals.