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Nov. 15, 2006 The system of taxonomy of flowering plants that has been in use since 1981, and which goes by the name of the Cronquist System, is now obsolescent, thanks to the appearance in 1998 of the APG System. ‘APG’ stands for ‘Angiosperm Phylogeny Group’. I suppose this should be hailed as a great new triumph in microbiology, but it is a real nightmare linguistically and lexicographically. In the Cronquist System, Plantae, or the Plant Kingdom, was divided into a dozen divisions, one of which was Magnoliophyta or Angiospermae, flowering plants. Magnoliophyta were subdivided into two classes, Magnoliopsida, which comprise dicotyledonous plants, or dicots, and Liliopsida, which comprise, monocotyledonous plants, or monocots. Dicots are such plants as oaks, elms, figs, maples, beans, grapes, melons, potatoes and a whole cornucopia of others. Monocots are palms, grains and grasses, lilies, tulips, onions, sugarcane and scores of others. Monocots tend to be sleeker, more streamlined and more slender than dicots, which are leafy, gnarled and heavy for the most part. Anyway, under Cronquist, a particular plant belonged to: 1) a kingdom (Plantae); 2) a division; 3) a class; 4) an order; 5) a family; 6) a genus; and 7) a species. These groups are called ‘taxa’ (plural of ‘taxon’). In addition to these taxa, there were other, interpolated taxa, like ‘subfamily’, ‘superorder’, etc., which I’ll just skip. A complete pedigree then had seven taxa, as for example, common wheat: wheat: kingdom—Plantae; division—Magnoliophyta; class—Liliopsida; order—Cyperales; family—Poaceae; genus—Triticum; species—vulgare. (Capitalizations are mandatory precisely as shown.) The APG classification ascends no higher than order. But in some cases two or more of the older orders have been merged. In other cases, an older order has been subdivided into two or more orders. This involves shifting the families around from order to order, creating new families, abolishing old ones and leaving some families unplaced so far. This might be compared to renaming and renumbering all the streets in New York City, while adding and destroying some streets, and then giving all the mail to the mailmen, with an instruction of, “Go to it!” Just yesterday I looked up ‘oleaster’ in Wikipedia. This corresponds to the genus Elaeagna or the family Elaeagnaceae. In my own notes and my own book on linguistics, I had Elaeagnaceae as a family in the order Proteales. But I am out of date; the family has been shifted to the order Rosales. Proteales still exist, however, and have even acquired an adventitious family, Nelumbonaceae, which used to be in Nymphaeales. Can you see the bedlam APG has wrought? Tear whole chapters out of your encyclopedias, scrap entries from your dictionaries, reject half the websites online. Undoubtedly, some will argue that this is an advance. The APG does reflect angiosperm phylogeny more accurately, being based solely on molecular comparison, rather than on general morphology. But it is practically worthless for the purpose of naming plants. For years or decades there will be contradictions, or should I say more contradictions than there are already. In fact, the 1998 version of APG is called APG I. In 2003, a revised version called APG II appeared. I suppose we can expect an APG III and an APG IV And the really annoying part is that no sooner will the APG be instituted than someone else will devise a newer and better scheme and APG will be defenestrated. Basically, the volume of change is tremendous. There were over 300 families in 60-odd orders, including hundreds of thousands of genera and species. All the pedigrees have been shot full of holes. This idea originated in Scandinavia of course. ------------ About the author Thomas Keyes: I have written two books: A SOJOURN IN ASIA (non-fiction) and A TALE OF UNG (fiction), neither published so far. I have studied languages for years and traveled extensively on five continents. Email: udikeyes@yahoo.com Comment on this article here! ------------ All articles are EXCLUSIVE to Useless-Knowledge.com and are not allowed to be posted on other websites. ARTICLE THIEVES WILL BE PROSECUTED! |
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