Here is an abbreviated classification or taxonomy of all the organisms presented in this website, as well as a few others of interest. This is not meant to be a complete listing of all living things, nor even a completely correct one, since these classifications change as new theories come into favor. One should realize that every one of the groupings presented below is a judgment call representing collective scientific opinion, rather than a hard fact.
The classification of living things into groups depends not only on their differences and similarities but also on the degree to which they are studied and understood. For example, lesser-studied types such as mollusks tend to be lumped together into broad classifications, while popular and easily-studied types tend to be divided into fine distinctions. For a prime example of this, pick up any field guide on birds, and see how many Warblers there are in it. Birds are widely considered to be "over-split" - divided into many different species and families that are really not different. Coincidentally, bird-watching is an extremely popular pastime among scientists and laymen alike. Conversely, mollusks are probably "under-split", but then mollusk-watching is no fun at all.
More: Classification of Marine Organisms ...