238 Cognitive Exploration of Language and Linguistics
Not only linguistics, but many other sciences such as physiology, ethology
(study of the behaviour of animals), evolution theory, anatomy, anthropology,
human geography, neurobiology study these issues. In fact only an interdisci-
plinary approach, in which various disciplines co-operate, can deal with the
genesis and spread of languages and can provide data of this kind.
10.2.2
Genetic relatedness of languages
Language classification has a rich tradition of trying to identify language
families. This metaphor suggests the existence of a genetic relatedness between
a number of languages, reflecting the relations between the members of a
human family. Languages that show a large number of common features in
phonology, lexicology, morphology and syntax stem from a common ancestor.
Thus, a number of languages from India, such as Hindi, Iranian languages,
Slavonic languages, Greek, Latin, Celtic languages, Romance and Germanic
languages are all members of one big language family, i.e. the Indo-European
language family. Establishing language families therefore means historical
research and reconstruction of older language forms, called proto-language and
of the great lines of historical sound shifts or structural changes that have
caused language differentiation. The latter were discussed in Chapter 9 on
historical linguistics.
Here in this section we will concentrate on the results of historical differen-
tiation. In addition to the notion of language family, language classification
now uses a more complex taxonomy. At the top we have the category of a
phylum, i.e. a language group which is unrelated to any other group. The next
lower level of classification is that of a (language) stock, i.e. a group of languages
belonging to different language families which are distantly related to each
other. Language family remains a central notion, emphasizing the internal links
between the members of such a family. In a number of cases, e.g. in the case of
Indo-European, the levels of phylum, stock and family coincide, but as Tables
4 and 5 show, in the many complex language situations in Africa, Asia and the
Americas, these distinctions are necessary. Language families are further
subcategorized into branches, e.g. the Western European branch of the Indo-
European family, branches are subcategorized into groups, e.g. the Romance
and Germanic groups in the Western European branch, and groups may branch
into subgroups. These terms are displayed and illustrated for a number of
African languages in Table 4. Table 5 gives a classification of the world’s major
linguistic areas. Table 6 offers a survey of the Indo-European family.