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Language Diversity


Combining different disciplines, Leiden University researchers work together to formulate innovative solutions to societal problems. Below is an example from the field of language and culture.

Overview research dossiers


Language as key to understanding humanity

Language offers new insights into our history, cultural differences, migration, and the way in which our brain processes information. This knowledge can in turn help us understand what it means to be human, as well as opening the way to many practical applications. In order to realise these goals, linguists at Leiden University work closely together with researchers from other disciplines, such as biologists, psychologists, archaeologists and historians.

<p>Birch bark letter, written in Cyrillic in the Karelian dialect of the archaic Finnish language (13th century)</p>

Birch bark letter, written in Cyrillic in the Karelian dialect of the archaic Finnish language (13th century)

Knowledge from thousands of years ago

Approximately 6,000 languages are spoken worldwide. The study of language gives us information on the history and migration of different nations from thousands of years ago, even when we have no archaeological or written sources available to us from that time. Communities that are geographically remote from one another sometimes use the exact same words. These similarities must somehow have been ‘transported’. By following the journey of language, we can find out more about the journey of the people who spoke it, and about the other communities they came into contact with. Through studying similar words and concepts in different languages we learn about the socio-cultural background of peoples.

Cultural differences are recorded in the language

The study of language systems teaches us that cultural information is recorded in the grammar. Many Amerindian languages encode how a person obtained a given piece of information. Did they hear it somewhere, did they see it with their own eyes, or did someone else tell it to them directly? Other languages, such as Dutch, do not have this kind of coding. We can say: ‘There was a fair’ without having to specify the source of this information. In some languages and cultures, it is considered very important to indicate the source of information, while in others it is not.

Language in our brain

The study of language diversity also provides insight into human biological and psychological development, including how we learn language, what languages our brain accepts, and how our brain processes language in reading and speech.

Multidisciplinary collaboration

Leiden University has an exceptional range of expertise in the field of language diversity, as well as knowledge of a great number of languages. Leiden researchers specialise in Africa, Native America, South and Central Asia, Southeast Asia and Oceania, East Asia and Siberia, or Europe. Leiden’s language researchers are also known for their collaboration with experts from other disciplines such as medical scientists, psychologists, education experts, biologists, geneticists, archaeologists and historians.

More information:
Leiden University Centre for Linguistics

Language as a time machine

By studying language you can reconstruct the history of different communities, even when no other historical sources, such as written documents, are available. In the coming years, researchers Willem Adelaar and Marian Klamer will be carrying out this kind of reconstruction in areas of great linguistic diversity.

The riddle of the Americas

To this day, researchers still do not know when North and South America were first populated. While archaeologists claim that there were no humans in this area until 15,000 years ago, linguistic research seems to suggest otherwise. This conclusion is based on the more than 175 genetic linguistic lines that have been identified by researchers throughout the region. These lines must have taken longer than 15,000 years to develop and spread. A thorough analysis of the linguistic lines can tell us much more about how the Americas were populated.

Comparing languages

Professor Willem Adelaar is working on the enigma of the Americas by comparing languages from Mesoamerica and the Andes. He has chosen these two regions because there are indications that the languages of the Andes region may have developed from languages that were once spoken in North and Central America. These are languages of which it is as yet unclear whether they are genetically related to one another or whether the two nations that spoke them were simply in contact with one another.

The Harakmbut, an Indian tribe from Peru of which William Adelaar examines the language.

The Harakmbut, an Indian tribe from Peru of which William Adelaar examines the language.

Relation between nations in Mesoamerica and the Andes

Adelaar has split his research into two parts. First he wants to identify the similarities between the languages of Mesoamerica and the Andes that can be traced to the earliest migratory flows between the two regions. To do this, all the available linguistic, archaeological and genetic knowledge on the peoples of Mesoamerica and the Andes will first be collected in a subproject. Armed with this knowledge, Adelaar and his colleagues can scan

the anguages in search of evidence of the relationship between the different communities. This vast investigation will be made possible through the knowledge of the regions and their languages that is amassed within Leiden University and through collaboration with geneticists. The researchers will also make use of the rapid advances in technology that now make it possible to compare ever greater datasets.

Searching for evidence of contact

Adelaar will also be searching language for evidence of later contact between the peoples of Mesoamerica and the Andes, roughly until the time of Columbus’ discovery of America. We know from archaeological sources that such contacts took place because of highly complex metalworking techniques that found their way from Peru to Mexico. Researchers have also found remarkable similarities in artistic expression between the peoples of the two regions. It seems unlikely that these meetings would have left no trace in the language. Adelaar is searching for evidence of these contacts, for instance through studying the external relations of the Purépecha (Mexico) and the Mochica (Peru). The former seem to display similarities with languages from the Andes region (such as Quechua or Aymara), and the latter with languages from Mesoamerica (such as Mayan).

More information:
The Linguistic Past of Mesoamerica and the Andes

Borrowing and inheriting in East Indonesia

It is not immediately clear why the Dutch word ‘goed’ resembles German ‘gut’ or English ‘good’. Is it because these languages share the same ancestor language, or is this word a loanword, like ‘sowieso’ or ‘computer’? It is sometimes difficult to differentiate between what languages ‘inherit’ and what they ‘borrow’, especially when looking at neighbouring languages that also happen to share the same ancestor language.

Forty languages on three small islands

In order to map the difference between ‘borrowing’ and ‘inheriting’ in language evolution, we have to study a situation in which borrowing takes place between unrelated languages, so that ‘inheriting’ can irrefutably be separated from ‘borrowing’. Such situations are rare in the world, but an example can be found in East Indonesia. On East Flores, Pantar and Alor, the local languages either belong to the Austronesian or to the Papua language family. These three islands jointly cover an area that is smaller than the Netherlands. Nonetheless, no

Marian Klamer in conversation with Teiwa-speakers from Lebang village (Pantar, Indonesia)

Marian Klamer in conversation with Teiwa-speakers from Lebang village (Pantar, Indonesia)

fewer than 40 different languages are spoken in this region. In addition, the languages in question are so diverse that some speakers who live only a few kilometres apart are utterly unable to understand each other. This has been the case for thousands of years, and speakers of these language families have been in contact with each other for a very long time, for instance through trade or marriage. Nowadays, most speakers use Indonesian as a relay language.

Reconstructing history and migratory flows

Professor Marian Klamer and her group of five researchers work in the region, studying a variety of linguistic contact contexts and trying to establish which words and structures have been borrowed and which inherited. Her team studies the circumstances in which these processes unfold and creates a reconstruction of the history and migrations of the different groups of people. All this provides information on the evolution of language in general, and the history of the people of Flores, Pantar and Alor in particular. 'We cannot rely on written sources to find out about their history, because these sources only go back a hundred years,' Klamer explains. 'And the deeper history requires archaeological research, which has not yet taken place here. We therefore have to rely on finding information in the languages themselves. Take kinship terminology (‘cousin’, ‘grand-child’), for example. These terms are strongly traditionally determined, but they also change form or meaning through contact, for example when the women of one language group marry into another group, and raise their children there. In addition, place names in language A form a link between a geographical location and the speakers of language A, even when these speakers live elsewhere. For example: what would it mean if we found Frisian place names in Drenthe?'

Research results useful for other disciplines

The results of this research are important not only for linguists; it can also be used as a starting point for research by historians, archaeologists and anthropologists. The project runs until 2019 and is supported by a VICI grant from the Dutch research institute NWO.

Insight into history

Not only is Adelaar and Klamer’s research interesting from a linguistic perspective, it also immediately impacts the local people. The researchers have many contacts within the communities they study. Their research also provides the local inhabitants with insights into their own history, language and culture. In addition, the languages studied in these two research projects are being properly documented, which means they will be preserved for posterity.

More information:
Reconstructing the past through languages of the present: the Lesser Sunda Islands

In search of the origin of all languages

There is a linguistic hypothesis that states that all languages from Europe to India originate from a single mother language: Proto-Indo-European. This language is thought to have been spoken thousands of years ago. Researcher Alwin Kloekhorst plans to use linguistic genealogy to study the very first split of Proto-Indo-European into the languages of the Indo-European family. This will help us to find out more about the origin of modern European languages, including Dutch.

Long prehistory

The Proto-Indo-European language is the hypothesised mother language of all languages within the Indo-European family. This language is thought to have been spoken around 3500 BC by nomads living in what is present-day Ukraine. When these nomads first began to spread throughout Europe and Asia, their language changed into a number of different dialects from which the modern European, Iranian and Indian languages developed. No written evidence of Proto-Indo-European has ever been found, but its existence has been assumed by linguists since the early 19th century.

Three scenarios on the origins of Anatolian

Until now there has been much confusion about how Proto-Indo-European split into the languages that we know today. One of the most important questions concerns the position of the Anatolian language branch, which consists of a group of languages that were spoken between 2000 BC and the year zero in Anatolia (Turkey), and which are the oldest known Indo-European languages. 

Three possible scenarios have been put forward in the academic debate regarding the origin of Anatolian. Scenario 1: Anatolian is a daughter of Proto-Indo-European. Scenario 2: More precisely, Anatolian is the daughter language that first split off from Proto-Indo-European. Scenario 3: Anatolian is a sister language of Proto-Indo-European. Despite the fact that Anatolian is clearly related to the other Indo-European languages, it cannot easily be fitted into the current genealogy. This is why some researchers have suggested that Anatolian is perhaps not so much a daughter of Proto-Indo-European as a sister.

Alwin Kloekhorst investigates an inscription on a potsherd

Alwin Kloekhorst investigates an inscription on a potsherd

Grandmother language

Alwin Kloekhorst hopes to elucidate the mysterious position of Anatolian by comparing Anatolian languages with various other groups in the Indo-European family. 'If we find evidence that Anatolian is not a daughter but a sister of Proto-Indo-European, we can trace Anatolian and Proto-Indo-European to a kind of grandmother language. This would mean that all Indo-European languages (including Dutch) have a much longer prehistory than we had so far assumed. And we are talking about hundreds, possibly thousands of years.' In order to investigate this hypothesis, Kloekhorst will be using cladistics, a kind of linguistic variation on genealogy, to establish very precisely the position of Anatolian within the Indo-European language family. Kloekhorst’s research project runs until 2020 and is supported by a VIDI grant from NWO.

More information:
Splitting the Mother Tongue: The Position of Anatolian in the Dispersal of the Indo-European Language Family

The effects of multilingualism

More than half of Europeans speak two or more languages. Linguist Lisa Cheng investigates the various forms of multilingualism in Europe from a linguistic, cognitive and sociological perspective. She looks for instance at the way in which minority languages influence the standard language of a country, and investigates the effect of multilingualism on cognitive capacity.

This research on multilingualism is supported by the European Commission and carried out in no fewer than eight different countries: the Netherlands, England, France, Germany, Italy, Spain, Slovenia and Croatia. Leiden University is co-ordinator of the project and is responsible for the collaboration within this large-scale project.

Influence on the standard language

One of the key questions in Cheng’s research is the extent to which minority languages (languages that are spoken by a minority of the population of a country, for instance by immigrants) and heritage languages (languages that are learnt at home but are not the standard language) influence the standard language of a country. Cheng: 'Did you know for example that the English youth of London speak very different English from the standard? We want to find out whether this is due to the migrant languages that are spoken in London and its surroundings. And if so, which languages? Which aspects of language (such as pronunciation, sentence structure, or word order) can be influenced, and which can’t?' These questions are studied by collecting recordings of English speakers between the ages of 18 and 25. The same research will is also conducted in the other participating countries, after which the data will be meticulously analysed.

Effects of multilingualism on cognition

Another component of the project is concerned with the potential advantages of multilingualism, for instance in terms of cognition. This addresses questions such as the following: How many languages do you need in order to have an advantage: two or three? Does it make any difference whether the languages resemble each other (German and Dutch) or whether they are very different (Chinese and Dutch)? Is it important to learn these languages at a young age, or does this not matter? These questions are also addressed in the eight countries listed above.

Contribution to European policy

The research results are very interesting from a linguistic perspective. And they can help assess European policy, for instance in the field of education. The goal of the European Commission is to ensure that every European citizen speaks three 

The effects of multilingualism

of the European languages fluently. The EU hopes by this means to protect language diversity and to stimulate language learning. The latter is important, says the EU, so as to make it easier for European citizens to find a job outside their own country, and in order to increase intercultural understanding within Europe. Cheng: 'But young people in Europe do not seem interested in learning a second language. So the question is how can you stimulate European people, especially young Europeans, to learn more languages?' With this project, the researchers hope to demonstrate, among other things, that the EU objectives should not only focus on ‘school languages’; in fact, heritage languages offer the same advantages. 'Once we have enough research results, we aim to issue this as an advisory document to the EU,' says Cheng.

Language policy in schools

The results of this project can also be used to formulate language policy in schools. European schools are increasingly facing classes of pupils with diverse cultural backgrounds who speak different languages. What learning methods work best to teach the standard language of a country in this kind of classroom? How can you make use of the knowledge and skills that the pupils already have? Potentially, this research can impact this entire field of policy.

More information:
Advancing the European Multilingual Experience (AthEME)

The evolution of Dutch

In order to compare languages, it is important to have a thorough knowledge of the specific languages you are studying. Gijsbert Rutten and his team are investigating the origin of Standard Dutch and the repression of ‘non-standard’ variants between 1750 and 1850.

The appearance of a single Dutch language

‘Standard’ Dutch as we know it did not always exist. In the eighteenth century, there was a lot more variation in the spoken and written language than there is today. Under the influence of the wave of nationalism that swept through Europe between 1750 and 1850, a discussion arose within Dutch associations and public bodies regarding the introduction of a single national standard language as a symbol of the nation. This led to the introduction of the Dutch language policy in the early nineteenth century: the government decided that there should be a single standard grammar and spelling. In his research, Gijsbert Rutten investigates how the ideas regarding a standard language developed in the Netherlands, and how the use of this standard language was imposed.

Dutch at school

In his research, Rutten focuses on such issues as education. During the introduction of Standard Dutch in schools, pupils were required to speak and write in class as much as possible in line with the standard, although they obviously spoke dialect with each other outside the classroom. Rutten wants to find out whether pupils were made aware of this distinction, and how exactly it worked. In order to investigate this phenomenon, Rutten studies textbooks, periodicals for educators, school inspection reports and the minutes of teachers’ associations. Many of these sources have never previously been studied.

The success of the policy

In addition Rutten also wants to know how successful the language policy of the nineteenth century was. The government had created official spelling rules and a grammar, but there were no laws to fully impose the mandatory use of these rules. It is known that there was resistance from

The Groot ABC Boek (‘Roosters book’), a popular school book used in the Netherlands in the 18th and 19th century. Collection Dutch National Museum of Education

The Groot ABC Boek (‘Roosters book’), a popular school book used in the Netherlands in the 18th and 19th century. Collection Dutch National Museum of Education

literary circles, for instance from well-known author Willem Bilderdijk. But perhaps an even more intriguing question is whether the official spelling and grammar were followed by ‘regular’ language users. To investigate this, Rutten is comparing language use in the eighteenth century, i.e. before the official rules, with language use in the nineteenth century. He uses sources such as private letters, diaries and newspapers in his research.

Contemporary Dutch

Studying the introduction of Standard Dutch allows us to find out more about the origins of contemporary Dutch. What myths are there regarding the origins of modern Dutch? The research results can also provide more general insights into how languages develop. How does everyday usage ensure that something becomes a grammatical rule? How does a standard language come into being? Rutten’s research project runs until 2019 and is supported by a VIDI grant from NWO.

More information:
Going Dutch. The Construction of Dutch in Policy, Practice and Discourse, 1750-1850


Scientists working in this multidisciplinary research area

  • Prof. dr. Lisa Cheng
  • Prof. dr. Alexander Lubotsky
  • Prof. dr. Maarten Mous
  • Prof dr. Willem Adelaar
  • Dr. Ahmad Al-Jallad
  • Dr. Felix Ameka
  • Dr. Yiya Chen
  • Dr. Jenny Doetjes
  • Mr. Dr. Aone van Engelenhoven
  • Prof. dr. Holger Gzella
  • Prof dr. Jaap de Jong
  • Prof. dr. Ton van Haaften
  • Prof. dr. Marian Klamer
  • Dr. Alwin Kloekhorst
  • Dr. Maarten Kossmann
  • Prof. dr. Claartje Levelt
  • Dr. Tijmen Pronk
  • Prof. dr. Johan Rooryck
  • Dr. Gijsbert Rutten
  • Prof. dr. Jos Schaeken
  • Prof. dr. Niels Schiller
  • Prof. dr. Rint Sybesma
  • Prof. dr. Ingrid Tieken-Boon van Ostade
  • Prof. dr. Arie Verhagen
  • Prof. dr. Marijke van der Wal

Prof. dr. Lisa ChengProfessor of Linguistics

Topics: multilingualism, heritage language, syntax, Bantu, Chinese

+31 (0)71 527 2104

Prof. dr. Alexander Lubotsky Professor of Comparative Indo-European Linguistics

Topics: Indo-European, Vedic Sanskrit, Avestan, Phrygian, history of languages

+31 (0)71 527 2190

Prof. dr. Maarten MousProfessor of African Linguistics

Topics: Cushitic languages, mixed language, bantu languages, youth languages

+31 (0)71 527 2242

Prof dr. Willem Adelaar Professor of Native American Languages and Cultures

Topics: languages of the Andes and Meso-America

+31 (0)71 527 2511

Dr. Ahmad Al-Jallad Assistant Professor of Arabic Language and Linguistics

Topics: ancient Arabic and North-Arabic language, inscriptions, historic Semitic linguistics

+31 (0)71 527 2223

Dr. Felix Ameka Assistant Professor African Linguistics

Topics: West-African languages, Kwa languages, Hausa, Fulfulde

+31 (0)71 527 2243

Dr. Yiya Chen Assistant Professor of Phonetics

Topics: phonetics, Chinese dialects, sound production and perception, pitch variation, sentence planning

+31 (0)71 527 1688

Dr. Jenny Doetjes Associate Professor of French Language and Culture

Topics: semantiek en syntaxis vanuit een cross-linguïstisch perspectief, Franse taalkunde

+31 (0)71 527 2181

Mr. Dr. Aone van EngelenhovenUniversity Lecturer

Topics: Indonesia , East Timor, Moluccan migrants in the Netherlands, historical linguistics, descriptive linguistics oral traditions, language and cognition

+31 (0)71 527 2072

Prof. dr. Holger Gzella Professor of Hebrew and Aramaic Language and Literature

Topics: Hebrew, Aramic, Semitic languages, historic and comparative linguistics, ancient Near-East

+31 (0)71 527 2255

Prof dr. Jaap de JongProfessor of Journalism and New Media

Topics: Journalism and new media, modern Dutch rhetoric/language use

+31 (0)71 527 2137

Prof. dr. Ton van Haaften Professor of Argumentation

Topics: language proficiency, argumentation, legal linguistics

+31 (0)71 527 2105

Prof. dr. Marian Klamer Professor of Austronesian and Papuan Linguistics

Topics: languages of Indonesia and the Pacific, language description, language typology, language contact, language history

+31 (0)71 527 2783

Dr. Alwin Kloekhorst Assistant Professor of Comparative Linguistics

Topics: Proto-Indo-European, Anatolian language, Hittite

+31 (0)71 527 2224

Dr. Maarten Kossmann Assistant Professor Berber Language

Topics: language contact in North-Africa and the Sahel zone, Berber, Dutch-Moroccan youth language, Songhay, Tuareg

+31 (0)71 527 2649

Prof. dr. Claartje Levelt Professor of First Language Acquisition

Topics: language development in babies and children, language perception, language production, babylab, phonological developmentchildren

+31 (0)71 527 2103

Dr. Tijmen PronkAssistant professor of Comparative Indo-European Linguistics

Topics: Indo-European linguistics, Slavic languages, accentology, etymology, dialectology

+31 (0)71 527 2224

Prof. dr. Johan Rooryck Professor of French Linguistics

Topics: morphosyntax of the Roman languages, core knowledge systems, evidentiality, possessions, anaphors

+31 (0)71 527 2049

Dr. Gijsbert Rutten Postdoctoral researcher of the History of Dutch

Topics: language variation, language change, history of Dutch, standardisation

+31 (0)71 527 2112

Prof. dr. Jos Schaeken Professor of Slavic and Baltic Languages and Cultural History

Topics: Russian language and culture, Church Slavonic, Old Prussian

+31 (0)71 527 2077

Prof. dr. Niels Schiller Professor of Psycho- and Neurolinguistics

Topics: experimental language sciences, psycholinguistics, neuro-linguistics, language disorders, multilingualism

+31 (0)71 527 4171

Prof. dr. Rint Sybesma Professor of Chinese Linguistics

Topics: syntaxis, talen van China, Mandarijn, schrift

+31 (0)71 527 2529

Prof. dr. Ingrid Tieken-Boon van Ostade Professor of English Historical Sociolinguistics

Topics: standardization of the English language (codification and prescriptivism), late modern English, English letter language

+31 (0)71 527 2163

Prof. dr. Arie Verhagen Professor of Dutch Linguistics

Topics: grammar, text, (cultural) evolution of language

+31 (0)71 527 4152

Prof. dr. Marijke van der Wal Professor of the History of Dutch

Topics: standardisation, language change, language variation, language history, ego documents

+31 (0)71 527 2134


Students learn directly from researchers

Language diversity is a central theme in the bachelor’s and master’s programmes in Linguistics. It is also studied in all Leiden University language, culture and regional study programmes. These programmes stimulate students to apply the newest linguistic insights to their own research. The annual Summer School in Languages and Linguistics offers students from Leiden University and beyond the opportunity to gain additional knowledge from inspired language experts from Leiden and abroad. Non-students can also benefit from the linguistic knowledge amassed at Leiden University, in the form of advice and programmes offered by the Academic Language Centre.

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