ABSTRACT
A very common pattern in systematic research is the attempt to establish the true relationships of some taxon whose position is uncertain in the existing state of our knowledge. The phylogenetic systematist will translate each possible relationship into a hypothesis about ancestry, and will try to work out the implications—including functional, chronological and distributional ones—of each hypothesis in as much detail as possible. Matrix analysis is a method commonly used today, and is undoubtedly useful at times, even though it provides no infallible method of achieving a natural or phylogenetic system. As practised by systematists, the initial stages of the method involve the preparation of what Americans call a 'checker board diagram', from which, with the aid of a good deal of arithmetical computation, several different types of numerical matrix can be derived. Matrix analysis is comparatively easy when the number of taxa and of characters involved is not very large.
