Rule 4 Genes and environment are both important The environment an organism finds itself in plays an important role in determining the options open to that individual. The genes which define an organism's makeup are also of fundamental importance. To understand ecology it is important to appreciate the fundamental nature of both of these factors and the fact that they interact Rule 5 Understanding complexity requires models. Ecology is a complex subject, with huge variation at almost every scale-millions of species, each with considerable genetic variation, varying numbers and ever-changing behaviors in a complex and dynamIc environment. To understand it, it is necessary to clearly identify specific questions and then formulate hypotheses which can be tested. It is often very useful to frame the hypothesis in mathematical terms to avoid ambiguity and confusion which are often inevitable in a verbal model Mathematical models are widely used in ecologyRule 4 Genes and environment are both important. The environment an organism finds itself in plays an important role in determining the options open to that individual. The genes which define an organism’s makeup are also of fundamental importance. To understand ecology it is important to appreciate the fundamental nature of both of these factors and the fact that they interact. Rule 5 Understanding complexity requires models. Ecology is a complex subject, with huge variation at almost every scale-millions of species, each with considerable genetic variation, varying numbers and ever-changing behaviors in a complex and dynamic environment. To understand it,it is necessary to clearly identify specific questions and then formulate hypotheses which can be tested. It is often very useful to frame the hypothesis in mathematical terms to avoid ambiguity and confusion which are often inevitable in a verbal model. Mathematical models are widely used in ecology