One of the first tenants of linguistics is that linguistic signs are arbitrary. By this, linguists mean that there is nothing about a book that requires it be called book and not hon, shu, libre, or horse. Well, mostly arbitrary, anyway.
Onomotopoeia are an obvious exception. I farted while paddling yesterday, and that got me thinking about how many words for farting have an /u/ /a/ /ae/ or similar sound–and very few have an /i/ sound in them. Wikipedia contributes:
- In Batak, put
- In Czech, prd
- In English, poot, toot
- In Finnish, prut, prööt
- In French, prout
- In Hebrew, pook פּוּק
- In Indonesian, pret, prett, tuut
- In Italian, prot
- In Japanese, bu ぶっ
- In Russian, pook пук
- In Thai pood ปู้ด
add that to your list of biological influences on language.
postscript: I was surprised at how many also had a p (which is closely related to f), and some sort of r. The Pidgin (HCE) fut always seemed much more onomotopoetic than fart to me. Fut may provide a nice hint to fart’s etymology, however: when pronounced by non-rhotic Brits, fart is a big, satisfying faht.