* Lack of comprehensive data: We don't have a complete record of all languages ever spoken, and many languages are spoken by small, isolated communities whose languages may not be documented.
* Defining "lost": There's no single definition of what constitutes a "lost" language. Does it mean no longer spoken by anyone? No longer passed down to children? No longer used in everyday life?
* Ongoing process: Language loss is a continuous process, not a sudden event. Languages can become dormant, revitalized, or merge with others, making it hard to definitively say when a language is "lost."
However, estimates suggest that languages are disappearing at an alarming rate:
* UNESCO: Reports that one language goes extinct every 14 days.
* Ethnologue: Estimates that about 2,500 languages are spoken today, with roughly half considered endangered or severely endangered.
* Other estimates: Some sources estimate that 90% of the world's languages could disappear by the end of the century.
Factors contributing to language loss:
* Globalization: The spread of dominant languages like English, Spanish, Mandarin, etc.
* Forced assimilation: Historical policies that marginalized or suppressed minority languages.
* Migration and urbanization: People leaving rural areas and moving to urban centers where dominant languages are spoken.
* Lack of language revitalization programs: Limited support for preserving and transmitting endangered languages.
It's important to note that language loss is a complex issue with various contributing factors. It's also a significant loss of cultural diversity and heritage.