Nobody likes losing things, but the outcome of any loss can always be measured on a basis of what is remaining. The loss of species from the Earth is important humanity, but the impact can only be realized if a view in proportional terms and from perspectives of what is remaining is considered. To estimate the importance of the current extinction rates, it is important to appraise the number of species that occupy the earth’s surface.
Among the most surprising things about science is the little information we have. It is amusing that one can assume that biologists are having a good idea of the number of species of living organisms existing on Earth, but this is not the case. The question is still a debate, and the estimations that that makes a range of three and five hundred million species (Mora 2). What is agreed upon, however, are that only very few proportions of the total amount are currently identified with science and has been adequately described? Other parts of the world have studied much, especially the tropical regions where there are different species specifically at high altitudes and the depths of the ocean, which prove difficult to identify, so the careful study is to be conducted to distinguish them. The number of expertise scientists, in the field of “taxonomy”—the study that in involves classification of plants and animals, are relatively limited. Accordingly, the counting of the animal task is even more difficult to accomplish than might at first appear.
The confusion that seems when some species in number is presented on Earth may seem surprising to non-biologists. However, the number of the sheered wealth of species comes with difficulty to assure that almost all the discovered species are valid and that are not duplicates, or that the ones described are a single species, in fact, include some species that are lumped together unintentionally. The herring gull, previously identified as a single species, Larus argentatus, for example, is discovered in coastal regions right around the world under the temperature zone along Northern Hemispheres—identified as circumboreal distribution. On the contrary, it occurs in different forms and different places and the close molecule study of the genetics of this gull has revealed that the supposed species have several closely similar resemblances to one another. The northern European herring gull is, therefore, L. Smithsonian's. A southern Europe, the yellow-legged gull, is L. michecalleis, an American gull is L. amenicus, and the Caspian gull is of an Asian Minor identified as L. cachinnans (Crawford 9). Therefore, a single species has transformed overnight to become at least five species
Doubts remain about the relationship of the similar white-headed gulls of Siberia. Among the problems here actually is the definition of species. The convenient opinion that two species cannot interbreed is not workable since interbreeding that occurs between several animals and plant species, which are morphologically different is often possible. In case population of organisms are sufficiently divergent in their outward form, or their physiology, or their pattern of behavior, and in case there is a difference in molecule genetic pattern, and then possibilities are that they are distinct species. The definition involves a synthetic approach, and the drawn lines around species will have a variation from one time to the other as much of information becomes available. Therefore, the task of identifying the number of species there are on earth becomes even more of an issue.
Mora, Camilo, et al. "How many species are there on Earth and in the ocean?" PLoS Biol 9.8 (2011): e1001127. (http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1001127)
Crawford, Ruth. "How many species are there on Earth and why to worry about it?" Journal of Sustainability 1.1 (2013): 9.