4 Microcosmology Microecosystems or microcosms are relatively small, closed or semi-closed ecosystems used primarily for experimental purposes. As such, they are living tools used by scientists to understand nature. | 4 Microcosmology INTRODUCTION Microecosystems or microcosms are relatively small closed or semi-closed ecosystems used primarily for experimental purposes. As such they are living tools used by scientists to understand nature. Microcosms literally means small world and it is their small size and isolation which make them useful tools for studying larger systems or issues. However although they are small as noted by Lawler 1998 microcosms should share enough features with larger more natural systems so that studying them can provide insight into processes acting at larger scales or better yet into general processes acting at most scales. Of course some processes may operate only at large scales and big long-lived organisms may possess qualities that are distinct from those of small organisms and vice versa . Because large and small organisms differ biologically it will not be feasible to study some questions using microcosms. However to the extent that some ecological principles transcend scale microcosms can be a valuable investigative tool. Microcosm as a term was originally used in ecology as a metaphor to imagine a systems concept Forbes 1887 see also Hutchinson 1964 . More recently Ewel and Hogberg 1995 and Roughgarden 1995 used microcosm as a metaphor for islands which have been used profitably as experimental units in ecology Klopfer 1981 MacArthur and Wilson 1967 . Microcosms are a part of ecological engineering because 1 technical aspects of their creation and operation often referred to as boundary conditions require traditional engineering and design and 2 they are new ecological systems developed for the service of humans. A large literature exists on the uses of microcosms primarily to develop ecological theory and to test effects of stresses such as toxic chemicals on ecosystem structure and function. This literature demonstrates a high degree of creativity in design of experimental systems as surveyed in the book length reviews by Adey and Loveland .
