Earth seems like such a good place for life to thrive, so is it a good place for life to get started?  Has life started on Earth more than once?  If so, where is it? Like this podcast? Please help us by <a href="https://www.thenakedscientists.com/donate">supporting the Naked Scientists</a>

Would self bone marrow transplants reverse aging?

Each week we set out to solve one of the world's weirdest, wackiest, funniest and funkiest scientific puzzles. And along with the answer there's a brand new question to think about for next time...