Environmental limit to genetic change. An alternative theorem of natural selection

Interest in molecular biology and cloning of animals is high. It is widely predicted that biotechnological improvements will revolutionize animal production on farms. The environment, as a constraint, is usually ignored. Yet, as organisms need environmental resources to live, there must come a point above which the genetically improved animals are no longer economically sustainable in farm environments. This recognition may be more important than ethical questions about biotechnology. This paper presents a fundamental theorem about natural selection and 'improvement' of organisms. This shows that, in evolution and on farms, the environment usually limits organisms and that, as a direct consequence, 'improvement of genotypes' beyond this limit is pointless, and does not occur in evolution.