In Greg Egan's "Diaspora" two of the successor human groups have chosen to leave. The Polis Citizens have been uploaded to run on dedicated computers which can then just travel through space as any other computer - but the Gleisner Robots have adopted artificial bodies which unlike biological human bodies are suitable for space travel. Not with any great speed, but by their nature the Gleisner Robots live at a steady pace, they're not bothered that it will take them a very long time to reach another star.

So in a sense these are both mind reconfigurations as well as physical, the Gleisner Robots have the required patience and the Citizens don't live at our pace or scale because their world isn't even real.

In Diaspora leaving turns out to be a lucky break, the Earth is sterilized by a relatively nearby gamma ray burst not long into the book and the subset of human descendants who went back into the trees are wiped out along with all other life on the planet.