ecoimmunology ecoimmunology ecoimmunology or ecological immunology is the study of the causes and consequences of variation in immunity. the field of ecoimmunology seeks to give an ultimate perspective for proximate mechanisms of immunology. this approach places immunology in evolutionary and ecological contexts across all levels of biological organization. classical, or mainstream, immunology works hard to control variation (inbred/domestic model organisms, parasite-free environments, etc.) and asks questions about the mechanisms and functionality of the immune system using a reductionist method. while ecoimmunology originated from these fields, it is distinguished by its focus to explain natural variation in immune functions. multiple institutes engage in ecoimmunological research, such as the center for immunity, infection, and evolution at the university of edinburgh and the max planck institute for immunoecology and migration. the us national science foundation has funded a research coordination network to bring methodological and conceptual unity to the field of ecoimmunology. the causes and consequences of immune variation have larger implications for public health, conservation, wildlife management, and agriculture. history ecological immunology is a discipline that uses ecological perspectives to understand variation in immune function. specifically, to explain how abiotic and biotic factors influence the variation in immune function. articles began discussing ecological contexts and of immune variation in the 1970s but matured into a discipline in the 1990s. ecoimmunology is an integrative field that combines approaches from evolutionary biology, ecology, neurobiology, and endocrinology. seminal papers seminal papers in the field include sheldon & verhulst's which proposed concepts from life history theory, trade-offs and allocation of resources between competing costly physiological functions, are a cause of variation in immunity one of the field’s seminal papers, by folstad and karter, was a response to hamilton and zuk’s famous paper on the handicap hypothesis for sexually selected traits. folstad and karter proposed the immunocompetence handicap hypothesis, whereby testosterone acts as a mediator of immunosuppression and thus keeps sexually-selected traits honest. although there is only moderate observational or experimental evidence supporting this claim up until now, the paper itself was one of the first links to be made suggesting a cost to immunity requiring trade-offs between it and other physiological processes. more recently, ecoimmunology has been the theme of three special issues in peer-reviewed journals, in philosophical transactions of the royal society b, in functional ecology, and in physiological and biochemical zoology (see