Why do nouns have gender?
Is there a rhyme or reason as to why some objects are feminine (mela, ragazza) and some are masculine (libro, ragazzo)? Also, are the ones that end in "e" (pane, cane) masculine or feminine and what are the rules pertaining to their plural forms?
Ok so for the most part:
ends in "A" = feminine = use "la", " la ragazza" : "the girl"
ends in "o" = masculine = use "il", " il ragazzo" : "the boy"
ends in "e" = plural feminine = use "le" , "le ragazze" : "the girls"
ends in "i' = plural masculine = use "i", "i ragazzi" : "the boys"
there are a few exceptions like "la tigre", these exceptions you just need to learn.
That's right :) In fact Old English (at the time of Alfred the Great) did have three genders and as many word endings as any other Indoeuropean language; Bodmer and Hogben, in an old book wataya recommended in this forum, The Loom of Language, argued that English is the European language that came the furthest from its roots, ending up being actually close to Chinese in a number of aspects. Nowadays it's limited to sex (bull vs cow, horse vs mare, and so on), but you can still hear the moon or a ship being referred to as "her".
Incidentally, it's funny how Indoeuropean languages disagree on their genders, e.g. the moon is feminine in Italian (la luna) but masculine in German (der Mond), and a young girl is neuter in German, much to Mark Twain's amusement.
Google knows all things. This source blames it on the Norman Conquest: http://uk.answers.yahoo.com/question/index?qid=20120115085010AA5XNR1 This source makes it more internal to English: http://en.wikipedia.org/wiki/Gender_in_English
An interesting quote from that book I mentioned:
"Though we have no first-hand knowledge about the origin of gender, we know enough to dismiss the likelihood that it had any essential connexion with sex. The most plausible view is that the distinction of gender in the Indo-European family is all that is left of a system of suffixes essentially like the Bantu prefixes. If so, the former luxuriance of such a system has been corroded in turn by nomadic habits and civilized living as primitive Aryan-speaking tribes successively came into contact with new objects which did not fit into the framework of a classification suited to the limited experience of settled life at a low level of technical equipment." (The Loom of Language, p.213)
Swahili and several languages have a number of roots that are prefixed or suffixed to words to help identify their "class", e.g. person, animal, purpose, material, and so on. The hypothesis is that in Indo-European languages those suffixes were simplified into a smaller system, and that only by chance or custom males and females were referred to by nouns in different classes. This would also explain why in German neuter nouns can refer to females or children and in Italian there are feminine words for the male organ.