Isolation IS a big factor:
* Limited contact: When groups are geographically isolated, they have less exposure to other ways of speaking. This means they are less likely to adopt new words, pronunciations, or grammatical structures from other groups.
* Independent evolution: Over time, these isolated communities develop their own unique ways of using language. This can be due to:
* Natural language change: All languages evolve and change, but isolated groups change independently.
* Borrowing from other languages: Isolated groups might have contact with other groups, but it's usually less frequent and from specific sources, leading to unique borrowings.
But, it's not the whole story:
* Social factors: Dialects also arise within communities that are not geographically isolated. These can include:
* Social class: Different social classes may develop distinct ways of speaking.
* Regional identity: Even within a large country, people in different regions may develop distinct dialects.
* Occupation: People in specific professions often develop their own unique jargon and ways of speaking.
* Migration and contact: While isolation plays a role, migration and contact with other groups can also contribute to dialect formation.
* Mixing and blending: As people move and interact, their languages can mix and blend, creating new dialects.
* Borrowing and adaptation: Contact with other languages can lead to the borrowing of words, pronunciations, and grammatical structures.
In summary:
Isolation plays a significant role in dialect formation, but it's not the only factor. Social, historical, and geographical factors all contribute to the diverse range of dialects we see around the world.