Identification of each individual from the massive inventory of living organisms requires appropriate classification system. This system allows not only identification of all specimens that are already collected, but also allows identification of the newly discovered organisms in the future. The classification system is robustly based on science and logic, so this system is universally applicable.
The classification system starts by grouping the specimens into two major categories namely animals and plants. In general, animals are grouped by the presence of appendages that implies the ability to move on their own while plants are grouped together based on the lack of appendages that implies their inability to move on their own. Careful examinations are made on specimens that do not show presence of appendages, as they may represent an individual’s stage in life (such as eggs and cocoons). Examinations include dissection and observation under the microscope to confirm the presence of animals and appendages within the specimen.
Plants are characterized by the presence of fibrous materials or structures associated with plants such as wood, leaves, roots, or branches. Plants also include small specimens such as mosses, lichens, mushrooms, and molds. Due to the complexity in plant group, classification and identification are only applicable to plant specimens with complete structures. Microscopic observation aids the observation of a distinct feature of plant known as cell wall. Cell wall is absent in animal specimens.
The approach of specimen classification proceeds with further differentiation within these two major groups. Sub-categories of animals are established based on the morphological features and functions of parts of animals such as done by Aristotle (Pellegrin 114). Similarly, sub-categories of plants are developed based on morphology and functions of various plant parts such as fruits, pollens, flowers, etc. Microscope is used to aid the observation of various animals’ and plants’ parts in the specimen to ensure that the differentiation process is done to a very detailed level. This is a very important step, as not all parts of the specimen can be differentiated through naked eye.This approach allows the development of sub-categories using a concept that have been well accepted within scientific communities.
Science requires that all procedures be replicable with a high degree of consistency, and this requirement applies to this biological classification system. In order to achieve this, biological classification is equipped with nomenclature system to identify and name individual organism. Categories and sub-categories bear specific names to allow consistent identification of any specimen. Using this nomenclature system, a living organism is eventually designated with two names consisting of genus and species names. This is done to identify a broader category and a specific identification. This nomenclature also allows identification of specimen that can be traced back to a larger categories. Furthermore, nomenclature system allows consistent naming of the specimens, so any identified living organism will be referred to the same genus and species names by all biologists.
For practical purposes, the current system is equipped with a key to identifying living organism based on the categorization procedures mentioned above. This key contains morphological features of various parts of the organism to help differentiate specimen into specific categories, and eventually to identify the genus and species of the specimen. This key is crucial not only in identifying existing specimen, but also in identifying new specimens. However, to ensure consistency in naming the living organism and to prevent false or multiple identifications (one species identified as two or more different species or vice versa), the rights for naming the living organism using this biological classification should be given to specific persons only, preferably those with appropriate training and experience in working with this system. Such person is called the taxonomic authority and the person’s name appears after the designated genus and species names.
Science advances with time and there will be new discoveries in the future. Despite the massive collections available to date, there are still possibilities of the discovery of new specimens. There may be places that have not been explored, and there are possibilities of the existence of living organisms that have not been found. Furthermore, there are also possibilities of new techologies that will allow faster and more detailed identification of living organism. One technology that will help improve the biological classification system is the technique to keep the specimens alive, or to preserve the specimen in its natural state. This tool will create better understanding of the parts and functions in each individual organism, for the parts will be in relatively natural forms and functions. This allows more precise differentiation based on this biological classification system.
Biological classification system is intended to identify and name each individual from a massive collection of specimens. This system offers clear and simple rules for categorizing living organism (Ereshefsky 200); thus allowing biologist to communicate using the same biological nomenclature. This system relies on differentiation based on morphology and function of various parts of the organism, and this system is equipped with a key to ensure consistent procedure of identification. This system will also allow identification of new organism by appointing highly trained and experienced persons with rights to assign new names to newly discovered organisms.
Ereshefsky, Marc. The poverty of Linnaean hierarchy - A philosophical stury of biological taxonomy. Cambridge, UK: Cambrige University Press, 2004. Print.
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Pellegrin, Pierre. Aristotle's classification of animals. London, England: University of California Press, 1982. Print.
Taxonomic approaches (Essay #3)
There are two general approaches in taxonomy known as “lumping” and “splitting”. Lumping describes tendency to combine several different non-inclusive classifications (taxa) into an inclusive single taxon, while splitting describes tendency to divide an inclusive single taxon into several non-inclusive taxa (Queiroz and Gauthier 27). Despite the differences of the two approaches, the decisions to lump or split occur quite frequently in taxonomy. In fact, both lumping and splitting are acceptable and are implemented in the field of taxonomy. These decisions often cause the instability in the nomenclature, as names and classifications may change. Fortunately, this instability can be prevented by opting to splitting as the main if not the only approach in taxonomy.
Currently, the field of molecular biology contributes to the taxonomy by providing tools to differentiate organisms based on their genetic make up (Johns and Avise 1481). The molecular technology allows analysis of organisms’ genotype in addition to phenotype characteristics. Splitting approcah supports this trend of identifying organisms to a molecular level based on genotypes, as the differentiation in taxonomy can now be done based on underlying biochemistry behind the phenotypes. Modern molecular approach is applicable not only to microorganism, but also to vertebrates. Same vertebrate species may be split into several different sub-species based on the molecular analysis of the genotypes.
Splitting has an advantage from biodiversity’s point of view, as splitting enriches the biodiversity. Splitting a taxon into several smaller taxa yields more categories and may eventually yield more species designations. Increase in species numbers contribute to the total numbers of existing species in a certain area, and increase in total numbers of species means higher biodiversity value. Population of wild species declines from 1970 to 2000 (Loh, Green and Ricketts 293), and this is a significant blow for biodiversity conservation. Therefore, increase in the numbers of species can potentially create positive force towards improving the biodiversity.
Increase in the numbers of species is also significant for increasing survival probability of living organisms in a particular area. Speciation process may result in species that are more superior that the predecessors. For instance, a new plant species with a small seed size will have greater chance of survival from predation compared to the predecessor, as the seed will not be readily discoverable by the predators (Willson and Whelan 196).
Similarly for animals, new species may have better ability to adapt to the changing environment; better hunting or foraging capability; and better reproductive success compared to the parent species. Splitting allows non-inclusive identification and classifications of these traits in parent species and in the subsequent species. This shows that the concept of splitting in taxonomy accommodates the abovementioned natural process. Splitting also allows identification of newly discovered species, or new classification based on available technologies.
Taxonomy is a growing science shaped by new discoveries as well as technological improvements. Splitting approach allows expansion of the taxonomic approach in accordance to these new discoveries and technologies. Splitting approach aligns with natural process of speciation and natural selection. Even with the advancement of molecular biology, splitting approach can still accommodate taxonomic classification based on this new technology. Furthermore, splitting allows expansion of the taxonomic classification without harming the exsiting structure; thus providing a robust systematic for species identification without the risk of re-arranging the existing systematic. Re-arrangement of existing systematic could produce complicated consequences such as taxonomic re-definition that may require rewriting of existing theories.
More importantly, splitting approach will indirectly contribute to the biodiversity richness by increasing the numbers of identified species. This increase will eventually improve the biodiversity indices. Splitting allows identification of improved phenotypes and genotypes of organisms. Similarly, splitting also allows identification of traits that are passed on from the predecessor. Splitting in taxonomy is known to accommodate natural speciation process, but splitting can potentially support non-natural or man-made speciation process. Man-made speciation exists in a branch of science namely bio-engineering where hybridization and DNA recombinant technology often result in emerging new breed of organisms. Taxonomic splitting allows identification of species of origin and allows the genetically-engineered organisms to be identified as different taxa. This supports the argument that taxonomic splitting enriches the biological inventory of living organisms.
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