Borean languagesBorean (also Boreal or Boralean) is a hypothetical linguistic macrofamily that encompasses almost all language families worldwide except those native to the Americas, Africa, Oceania, and the Andaman Islands. Its supporters propose that the various languages spoken in Eurasia and adjacent regions have a genealogical relationship, and ultimately descend from languages spoken during the Upper Paleolithic in the millennia following the Last Glacial Maximum. The name Borean is based on the Greek βορέας, and means "northern".
Nostratic languagesNostratic is a hypothetical macrofamily, which includes many of the indigenous language families of Eurasia, although its exact composition and structure vary among proponents. It typically comprises Kartvelian, Indo-European and Uralic languages; some languages from the similarly controversial Altaic family; the Afroasiatic languages; as well as the Dravidian languages (sometimes also Elamo-Dravidian). The Nostratic hypothesis originates with Holger Pedersen in the early 20th century.
Language isolateA language isolate is a language that has no demonstrable genetic relationship with another language. Basque in Europe, Ainu in Asia, Sandawe in Africa, Haida in North America, Kanoê in South America, and Tiwi in Australia are all examples of language isolates. The exact number of language isolates is yet unknown due to insufficient data on several languages. One explanation for the existence of language isolates is that they might be the last remaining branch of a larger language family.
Historical linguisticsHistorical linguistics, also termed diachronic linguistics, is the scientific study of language change over time. Principal concerns of historical linguistics include: to describe and account for observed changes in particular languages to reconstruct the pre-history of languages and to determine their relatedness, grouping them into language families (comparative linguistics) to develop general theories about how and why language changes to describe the history of speech communities to study the history of words, i.
Afroasiatic languagesThe Afroasiatic languages (or Afro-Asiatic, sometimes Afrasian), also known as Hamito-Semitic or Semito-Hamitic, are a language family (or "phylum") of about 400 languages spoken predominantly in West Asia, North Africa, the Horn of Africa, and parts of the Sahara and Sahel. Over 500 million people are native speakers of an Afroasiatic language, constituting the fourth-largest language family after Indo-European, Sino-Tibetan, and Niger–Congo. Most linguists divide the family into six branches: Berber, Chadic, Cushitic, Egyptian, Semitic, and Omotic.