Video: "The linguistic genius of babies" by Patricia Kuhl at TED Talk. http://www.ted.com/talks/patricia_kuhl_the_linguistic_genius_of_babies
What does preserving a language really means? Record it and preserve it in archival? No. Teach a language to others? No.
To truly preserve a language is to speak (manually or vocally, depending on which language it is) to babies in a native environment, as shown an example in the video: a mother (one of 800 people in the world) speaks Koro to her baby.
Why? It has to do with your brain -- the critical period from birth to age seven.
A study shows that at 6-8 month old babies don't discriminate sounds of different language, but in an amazing short time, at 10-12 month old babies turn head to sounds of a language of their own culture. It is a 2 month critical period. They are absorbing certain sounds of the language and shaping in their brain.
Researchers compare each component of nonreferential babbles with the phonetic inventory of an adult signlan. Yonekawa (1984) suggested the number of primes in each parameter such as handshape, movement and location. In a participant, 29% of handshape, and 54% of movement inventory in adult JSL were used in non0referential gestures. discuss that nonreferential babbles with the phonetic inventory of adult JSL.
Petitto and Marentette (1991) showed that 32% of the handshape and 54% of the movement that made up the phonetic inventory of adult ASL were observed in manual babbling. These nonreferential gestures are produced before the onset of signed words.
Native-sign-language people who are culturally Deaf around the world are truly living preservers of their native signed languages and culture, passing on to next generations.
This documentation project follows a baby's language acquisition, literacy development, and phonological acquisition in sign language, specifically ASL, week by week from gazing at birth to manual babbling, to first words just before the first birthday in a natural native-ASL environment and visual culture.
The second-year and third-year documentation continues to follow the same child's language and phonological acquisition and literacy development in ASL on a weekly basis from the one-word stage to two-word and multiple utterances.
The documentary continues to follow the same child's ASL language and literacy development on a regular basis from age three to four. It surveys ASL phonological acquisition and more complex utterances.
These posts on ASL-English bilingualism, language acquisition, and bilingual education may be of an interest for parents who raise a bilingual-bimodal child in ASL (or another signed language) and English (or another written and/or spoken language of its respective) as well as informative and educational for ASL specialists, educators, and professionals.