(Obafemi Awolowo University Press, 1980-11-18) Segun, A. O.
The topic, laws of arrangement, concerns the most fundamental and inclusive aspects of life sciences. It will deal with' the scientific term, taxonomy a word derived from two Greek words, "taxis" which means arrangement and "nomos" law. A branch of biology which used to be called "natural history" deals with the diversity of organisms within their environment. This is now split into the two separate branches of systematic and ecology. Systematic is involved with the descriptions, classification and all relationships among species. It therefore, includes taxonomy which is the theory and practice of classifying all organisms, both living and fossil, into a grand overall scheme. It should be noted that classification of organism is not the end of a taxonomist's concern, he is also interested in species formation, factors of evolution, structure of natural populations, biogeography, and the entire broad field of comparative biology.