From: ravi
afaik, life did develop in a non-sexual way. sex is just one imperfect way to reproduce. it comes with benefits and disadvantages. bacteria seem to have chosen an interesting middle path, often exchanging DNA (to get the benefits) but reproducing asexually or sexually.
^^^^^ CB: Current theory is that life originated 3 billion years ago and method of reproduction was cloning. Sex for reproduction originates 1.7 billion years ago, because sexual reproduction creates more variations in offspring , which is a general selective advantage.
Birds and the bees, flowers and the trees. Even plants have sex.