Every little thing has a purpose, at the same time, it has no purpose because this whole thing is a game. It is the existence which is total, beyond purpose. So you can say, virtually there is no purpose. If at all you have to pin down to a purpose then the purpose of nature is to take you to the Source, is to remind you of the Source, connect you to your Source.
Sri Sri Ravi ShankarEverything is cleansed and purified by the rains, and the Earth blossoms in beauty.
Sri Sri Ravi Shankar