I wouldn't sail this ship if I were you
1. There was a switch on a metro train, and somehow something hit it.
2. It was a warm Sunday in July, and there were major delays. In the third carriage, a builder and a singer got to talking over the next hour, and later on they went out of their way to share part of the journey home.
3. Ten years later, they had a baby daughter, who was brown and perfect and who liked to play among the lavender bushes.
4. The daughter had a daughter who had a daughter, and so on for a few hundred more generations. Eventually nearly everyone on the planet was descended from her; and her lavender-loving genes spread out into space.
5. There were seven more races that could perhaps be called human before the race between disasters and ingenuity took a sinister turn. But by then, the seventh humans had made something rather like robots in their own image, and the robots survived. They spent some millions of years being confused between a number of simulation cultures, but eventually they decided that they probably had the right reality and commenced to live in it.
6. The robot societies spread out over the Galaxy, though they did it the slow way. Fortunately, they could afford to wait; though, by the time they had reached some of the more distant stars, they were much-changed.
7. Eventually, one by one, the robot stars winked out, leaving an occasional lost city hurtling through the void on planets that had come loose from their systems. And there were three or four other civilisations that came from different places, and one or two of them knew of the lost cities and told stories about what they thought might have happened there. Though they were never quite right, it must be said.
8. The Universe gently skated over the crest of its near-infinite expansion and began to draw back in. By this time life had more or less worn itself out, though it had a few brief and bright late flowerings in the heat and chaos near the end of time. It seemed there was a chain connecting their feverish stories to the old ones, though there is not enough space in anyone’s mind to enumerate the links of it.
9. Time ended and it all began again.