<P> In 1859, Charles Darwin and Alfred Russel Wallace provided a compelling account of evolution and the formation of new species . Darwin argued that it was populations that evolved, not individuals, by natural selection from naturally occurring variation among individuals . This required a new definition of species . Darwin concluded that species are what they appear to be: ideas, provisionally useful for naming groups of interacting individuals, writing: </P> <P> I look at the term species as one arbitrarily given for the sake of convenience to a set of individuals closely resembling each other...It does not essentially differ from the word variety, which is given to less distinct and more fluctuating forms . The term variety, again, in comparison with mere individual differences, is also applied arbitrarily, and for convenience sake . </P> <P> The commonly used names for kinds of organisms are often ambiguous: "cat" could mean the domestic cat, Felis catus, or the cat family, Felidae . Another problem with common names is that they often vary from place to place, so that puma, cougar, catamount, panther, painter and mountain lion all mean Puma concolor in various parts of America, while "panther" may also mean the jaguar (Panthera onca) of Latin America or the leopard (Panthera pardus) of Africa and Asia . In contrast, the scientific names of species are chosen to be unique and universal; they are in two parts used together: the genus as in Puma, and the specific epithet as in concolor . </P> <P> A species is given a taxonomic name when a type specimen is described formally, in a publication that assigns it a unique scientific name . The description typically provides means for identifying the new species, differentiating it from other previously described and related or confusable species and provides a validly published name (in botany) or an available name (in zoology) when the paper is accepted for publication . The type material is usually held in a permanent repository, often the research collection of a major museum or university, that allows independent verification and the means to compare specimens . Describers of new species are asked to choose names that, in the words of the International Code of Zoological Nomenclature, are "appropriate, compact, euphonious, memorable, and do not cause offence". </P>

Difference between a scientific name and a common name
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