Biological systematics: the state of the art
واصفات البياناتعرض سجل المادة الكامل
To some potential readers of this book the description of Biological System atics as an art may seem outdated and frankly wrong. For most people art is subjective and unconstrained by universal laws. While one picture, play or poem may be internally consistent comparison between different art products is meaningless except by way of the individual artists. On the other hand modern Biological Systematics - particularly phenetics and cladistics - is offered as objective and ultimately governed by universal laws. This implies that classifications of different groups of organisms, being the products of systematics, should be comparable irrespective of authorship. Throughout this book Minelli justifies his title by developing the theme that biological classifications are, in fact, very unequal in their expressions of the pattern and processes of the natural world. Specialists are imbibed with their own groups and tend to establish a consensus of what constitutes a species or a genus, or whether it should be desirable to recognize sub species, cultivars etc. Ornithologists freely recognize subspecies and rarely do bird genera contain more than 10 species. On the other hand some coleopterists and botanists work with genera with over 1500 species. This asymmetry may reflect a biological reality; it may express a working practicality, or simply an historical artefact (older erected genera often contain more species). Rarely are these phenomena questioned.