Taxonomy: Why we need it?

In my last post, I had commented on why plants are important to us and why we need to know more about plants. Carrying on with that line of thought, I thought it fit to touch the topic of Taxonomy. The number of plant species on earth is estimated to be in excess of 400,000 and there is a whole discipline that deals with the naming and cataloging of these plant species. This is the Plant Taxonomy field which started in a systematic, scientific manner with Carolus Linnaeus (1707-1778), who is known as the father of taxonomy. He gave us the binomial system of classification, grouping organisms with similarities in a hierarchical fashion. Though much has changed in this field since the times of Linnaeus, the binomial nomenclature using the genus and species name in Latin is still used.

Why do we need Taxonomy? One would think that for as long as the human race has been on the planet, one would know most of the co-habitants. And then there is the question as to WHY do we need to know the names of the plants around us? After all, we don’t even know what our next door neighbor’s name might be, so why bother learning the names of the plants. Well, sometimes it is good to know the name for practical reasons, for example knowing what a poison ivy looks like or identifying a plant as poison ivy may save us from unwanted miseries. But, on a more academic level, identifying and cataloging plants gives us better insights about the plant. It may add to our knowledge of the evolution of plants. Once identified as a member of any given family, we can deduce a lot of information from prior knowledge of that family. For instance it may fall into a family with a lot of plants having medicinal properties. One may then wonder and test if this plant may also have such properties. It allows designing proper methods for caring for the plants. Of course, going by the fact that diversity is an integral part in improving our stocks, we must diligently protect and preserve the flora and fauna of earth.

Despite over 250 years of cataloging, we are still oblivious to the full extent of floral diversity that surrounds us. And then there is the added confusion of how what we know is interconnected from an evolutionary point of view. Many a times, the plants are incorrectly classified under a family or a genus due to their ambiguous morphological features. However, with the power of DNA fingerprinting and other molecular tools along with the many classification techniques, such taxonomical puzzles can be successfully resolved. For example, just recently, the world’s largest flower sporting plant, Rafflesia, which has mystified scientist for over 200 years about its taxonomical position, was shown to be actually related to members of family Euphorbiaceae which have very small flowers.

Many new species and genus are being discovered with time and many still remain hidden from the human race. In 2001 scientist found a new conifer Xanthocyparis vietnamensis which provides a missing link to the true and false cypresses. Unfortunately, this plant was already on the verge of extinction when it was discovered.It is listed as an endangered species. This was the second conifer to be discovered in recent years, after 1948. Wollemi nobilis, popularly but incorrectly known as Wollemi pine (because it is not a pine, but is related to members of Araucariaceae) was discovered in 1994 and is a living fossil. In 2002 Kress and Larsen discovered a new genus of the ginger family (Zingiberaceae) called Smithatris. These are but a few examples of how taxonomists are discovering, identifying and preserving the flora of earth.