This question already has an answer here:
I've been playing on a world since 1.6.4 and I have quite a bit of stuff built up (a massive subway network, a castle, a huge village, etc) and I don't want to start a new map, but I haven't seen anything from the new updates. No horses, painted deserts, or nary a new flower anywhere to be seen.
Is there a way to update my world map so that it'll include the new stuff into it? I'm playing single player locally. Thanks!