the art of reading, writing, or arithmetic had developed. Application of ecological knowledge led to development of agriculture, animal husbandry, medicines, fisheries, and so on. Modem ecology is a relatively young science and, unfortunately, there are so few books on applied ecology. The purpose of ecology is to discover the principles that govern relationships among plants, animals, microbes, and their total living and nonliving environmental components. Ecology, however, had remained mainly rooted in botany and zoology. It did not permeate hard sciences, engineering, or industrial technologies leading to widespread environmental degradation, pollution, and frequent episodes leading to mass deaths and diseases.