Historical linguistics in the context of "Languages of Taiwan"

African historiography is a branch of historiography involving the study of the theories, methods, sources, and interpretations used by scholars to construct histories of Africa. Most African societies recorded their history via oral tradition, resulting in a lack of written records documenting events before European colonialism. African historiography has therefore lent itself to contemporary methods of historiographical study, the utilisation of oral sources, and the incorporation of evidence derived from various auxiliary disciplines, differentiating it from other continental areas of historiography due to its multidisciplinary nature.

Oral historians utilised various sources from their communities in crafting socially-consolidated histories which were then passed down through generations, with traditions serving as contemporary documents of messages from the past. Early written history about Africa was largely undertaken by outsiders, each of which had their own biases. Colonial historiography was Eurocentric and propagated racist theories such as the Hamitic hypothesis. African historiography became organised in the mid-20th century, and initially involved the refutation of colonial narratives. Nationalist histories sought to generate patriotism and sustain the multi-ethnic nation states, and African historiography saw a movement towards utilising oral sources in a multidisciplinary approach alongside archaeology and historical linguistics. Following growing pessimism about the fate of the continent, Marxist thought became popular, and contributed to a more critical study of colonialism. From 1981 UNESCO began publishing the General History of Africa, edited by specialists from across the continent. The 1980s saw universities struggle amid economic and political crises, resulting in the migration of many scholars (largely to the United States), and the discipline remains critically underfunded. Historians of Africa in the 21st century focus more on contemporary history than precolonial history, and are less ideological than their predecessors as the discipline has taken on a more pluralist form.

A language family is a group of languages related through descent from a common ancestor, called the proto-language of that family. The term family is a metaphor borrowed from biology, with the tree model used in historical linguistics analogous to a family tree, or to phylogenetic trees of taxa used in evolutionary taxonomy. Linguists thus describe the daughter languages within a language family as being genetically related. The divergence of a proto-language into daughter languages typically occurs through geographical separation, with different regional dialects of the proto-language undergoing different language changes and thus becoming distinct languages over time.

One well-known example of a language family is the Romance languages, including Spanish, French, Italian, Portuguese, Romanian, Catalan, Romansh, and many others, all of which are descended from Vulgar Latin. The Romance family itself is part of the larger Indo-European family, which includes many other languages native to Europe and South Asia, all believed to have descended from a common ancestor known as Proto-Indo-European.

Language change is the process of alteration in the features of a single language, or of languages in general, over time. It is studied in several subfields of linguistics: historical linguistics, sociolinguistics, and evolutionary linguistics. Traditional theories of historical linguistics identify three main types of change: systematic change in the pronunciation of phonemes, or sound change; borrowing, in which new features (often, new words) enter a language or dialect as a result of influence from another language or dialect; and analogical change, in which the shape or grammatical behavior of a word is altered to more closely resemble that of another word. Research on language change generally assumes the uniformitarian principle—the presumption that language changes in the past took place according to the same general principles as language changes visible in the present.

Language change usually does not occur suddenly, but rather takes place via an extended period of variation, during which new and old linguistic features coexist. All living languages are continually undergoing change. Some commentators use derogatory labels such as "corruption" to suggest that language change constitutes a degradation in the quality of a language, especially when the change originates from human error or is a prescriptively discouraged usage. Modern linguistics rejects this concept, since from a scientific point of view such innovations cannot be judged in terms of good or bad. John Lyons notes that "any standard of evaluation applied to language-change must be based upon a recognition of the various functions a language 'is called upon' to fulfil in the society which uses it".

In historical linguistics, sister languages are languages that are descended from a common ancestral language. Every language in a language family that descends from the same language as the others is a sister to them.

A commonly given example is of Urdu and Hindi (the standardized registers of the Hindustani language), which are mutually intelligible with each other. Also, the Romance languages, each of which is a continuation of Vulgar Latin. Italian and French (both Romance languages) have about 89% lexical overlap, meaning 89 percent of words share the same characteristics and root origins. Similarly, Spanish and Portuguese also have about 89% lexical overlap. Spanish and Romanian overlap less, about 67%, because while Spanish and Portuguese have undergone Arabic influence, Romanian has undergone many different influences over the years, particularly from the Slavic languages and Greek. Along with a large amount of shared vocabulary, the Romance languages share numerous features of morphology and syntax because they are all continuations of their common ancestor, Latin.

The Rigveda or Rig Veda (Sanskrit: ऋग्वेद, IAST: ṛgveda, from ऋच्, "praise" and वेद, "knowledge") is an ancient Indian collection of Vedic Sanskrit hymns (sūktas). It is one of the four sacred canonical Hindu texts (śruti) known as the Vedas. Only one Shakha of the many survive today, namely the Śakalya Shakha. Much of the contents contained in the remaining Shakhas are now lost or are not available in the public forum.

The Rigveda is the oldest known Vedic Sanskrit text. Its early layers are among the oldest extant texts in any Indo-European language. Most scholars believe that the sounds and texts of the Rigveda have been orally transmitted with precision since the 2nd millennium BCE, through methods of memorisation of exceptional complexity, rigour and fidelity, though the dates are not confirmed and remain contentious until concrete evidence surfaces. Philological and linguistic evidence indicates that the bulk of the Rigveda Samhita was composed in the northwestern region of the Indian subcontinent (see Rigvedic rivers), most likely between c. 1500 and 1000 BCE, although a wider approximation of c. 1900–1200 BCE has also been given.

In the tree model of historical linguistics, a proto-language is a postulated ancestral language from which a number of attested languages are believed to have descended by evolution, forming a language family. Proto-languages are usually unattested, or partially attested at best. They are reconstructed by way of the comparative method.

In the family tree metaphor, a proto-language can be called a mother language. Occasionally, the German term Ursprache (pronounced [ˈuːɐ̯ʃpʁaːxə] ; from ur- 'primordial, original' + Sprache 'language') is used instead. It is also sometimes called the common or primitive form of a language (e.g. Common Germanic, Primitive Norse).

The Mayan languages form a language family spoken in Mesoamerica, both in the south of Mexico and northern Central America. Mayan languages are spoken by at least six million Maya people, primarily in Guatemala, Mexico, Belize, and Honduras. In 1996, Guatemala formally recognized 21 Mayan languages by name, and Mexico recognizes eight within its territory.

The Mayan language family is one of the best-documented and most studied in the Americas. Modern Mayan languages descend from the Proto-Mayan language, which has been partially reconstructed using the comparative method. The proto-Mayan language diversified into at least six different branches: the Huastecan, Quichean, Yucatecan, Qanjobalan, Mamean and Chʼolan–Tzeltalan branches.

In historical linguistics, cognates or lexical cognates are sets of words that have been inherited in direct descent from an etymological ancestor in a common parent language.

Because language change can have radical effects on both the sound and the meaning of a word, cognates may not be obvious, and it often takes rigorous study of historical sources and the application of the comparative method to establish whether lexemes are cognate. It can also happen that words which appear similar, or identical, in different languages, are not cognate.