It is really interesting! I find it very similar to english though. Cows don't actually make a sound anything like "moo", and birds don't "chirp". I think you

It is really interesting! I find it very similar to english though. Cows don't actually make a sound anything like "moo", and birds don't "chirp". I think you're right on when you say it's cultural. Another important thing that shapes these things in Japanese is just how old the culture is. So much is inherited from ancient times...