Many researchers in linguistic anthropology study how languages are related. For example, German and English are more similar to each other than either one of them is to French. Researchers have hypothesized that German and English developed out of a common language, whereas French is closely related to Spanish and Italian. By comparing languages, linguistic anthropolgists are determining how long ago they split apart and where their speakers migrated. In fact, some linguistic anthropologists are working on the premise that by comparing all the world's languages, they can construct the original human language .
Other researchers are working to preserve endangered languages (eg. various Native Canadian languages, Australian Aboriginal languages, various African tribal languages) where there are very few native speakers. This involves language documentation where the language is documented in terms of its grammar, its lexicon, and its oral traditions such as its stories, songs, and religious texts. As well, researchers are working to revitalize endangered languages through political, community, and educational means to increase the number of active speakers. For instance, the Rosetta Project is a global collaboration of speakers and researchers working to develop a version of the Rosetta Stone to last until 12,000 AD. The intention is to create a platform for comparative linguistic research and education, as well as a linguistic tool that might help in the recovery or revitalization of lost languages in the future.
Other researchers are focusing on grammatical change and the changing patterns of language use and how they both form part of larger social changes.á For example, many cultures have young people who decide to move away and live elsewhere, taking their language with them and modifying it for their purposes. Researchers are studying how these language shifts are being assimilated into the original language, resulting in an overall language shift. For instance, in Canada French is on the decline except in Quebec, where it is actually on the rise and English is on the decline.