The Experimental Zoology Group (EZO) offers a number BSc courses that convey the basic principles of zoology to students. These basic principles help to understand how animals are able to function (i.e. survive and reproduce) in their natural environment. EZO also offers a number of MSc courses that build on and expand the principles from the BSc courses. These MSc courses prepare students for an MSc thesis at EZO. To properly understand the functioning of animals, often a quantitative approach is needed in which the complex biological reality is reduced to its essential parts.