Here's a breakdown of the reasons:
* Shared Proto-Polynesian Origins: These languages evolved from a common ancestor, Proto-Polynesian, which was spoken by the ancestors of Polynesians who migrated across the Pacific thousands of years ago.
* Sound Changes: While the languages have diverged over time, they have retained many similar sound systems and grammatical structures. This is because they share a set of sound changes that occurred after Proto-Polynesian broke up.
* Vocabulary: They also share a significant number of cognates (words with a common origin) due to their common ancestry.
Examples of similarities:
* Vowel systems: All three languages have similar vowel systems, with five or six vowels.
* Consonant sounds: They share many consonant sounds, such as /p/, /t/, /k/, /m/, /n/, and /ŋ/.
* Grammatical structures: Their grammatical structures share similarities, such as the use of prefixes and suffixes.
However, it's important to note:
* Distinctive Features: While they sound similar, there are also distinct features that differentiate the languages. For example, Tongan has more complex consonant clusters than Samoan and Māori.
* Mutual Intelligibility: While speakers of these languages might understand some words and phrases from each other, they are not mutually intelligible. They are distinct languages with their own unique vocabulary, grammar, and pronunciation.
Overall, the similarities between Samoan, Tongan, and Māori are a testament to their shared ancestry and the powerful influence of Proto-Polynesian.