An interesting example of how Portuguese evolved from Latin is that "Culus" lost the "l", became "Cuu" and then got simplified into "Cu", while in spanish it went into a more conservative route. The same thing happened to the word, "Vŏlo", that became "Voo", another similar thing happened with the word "Manus", that becaume "Măo", it's an interesting pattern.
That came into my mind after Gallop's thread.