Here's why:
* Historical Development: Both languages evolved independently, with NZSL primarily influenced by British Sign Language in the 19th century. However, over time, NZSL developed its own unique grammar, vocabulary, and signs.
* Sign Differences: While some signs may share similarities, there are significant differences in how signs are formed, their meanings, and their use in the grammar of each language.
* Cultural Influences: NZSL reflects the unique culture and history of New Zealand, while BSL reflects British culture and history. This difference is evident in the signs used for specific concepts or cultural references.
Just like spoken languages, sign languages are distinct entities with their own structure and nuances. While some understanding may be possible between sign language users from different countries, communication can be challenging.
It's essential to remember that sign languages are not simply visual representations of spoken languages; they are fully-fledged languages with their own grammar and syntax.