[The Saucepan Man]

in none of my readings of tolkien have i heard much, if anything ,about evolution only creation

You are quite right, Eggy. Whatever his personal beliefs may have been (and I agree with others that religious faith and evolutionism are not necessarily mutually exclusive), his works certainly appear to be based upon creation rather than evolution.

Even this:

Hobbits were an "offshoot" of the human race, meaning they must have shrunk at some point through nature.

is not necessarily the case. As far as I am aware, there is nothing definitive in Tolkien's works to suggest that Hobbits evolved from Men, rather than simply awakening as a short sub-group of Men. Indeed, given the timescales involved, the latter seems to me to be far more likely.