Inheritable variation occurs widely in many different creatures, sometimes over long time periods, forming a persistent part of the organisms' abilities to adapt to their environments. What distinguishes persistent variation from transitory cases? An insect study system will be used to study a persistent case affecting the cellular "machinery" of energy processing common to all living things. How do the chemical and genetic effects of this variation interact with natural environments to maintain the variation, and how the system of variation has evolved as species carrying it have adapted to new habitats? Hopefully, general rules governing evolutionary change will emerge.
These results and their implications will shed important light on problems of concern to human society. For example, energy processing mechanisms in domestic crop animals and plants are no less variable than in these test insects. Many crop species have longer lives and are harder to use for initial study of adaptive principles than the test system. But there is good reason to believe that its results will apply to such crop species, and will assist in selective breeding to maximize food yield in changing agricultural environments. Equally, genetic aspects of conservation of rare species, and of environmental management in general, will be informed by this work in the same ways.
