This week's question involves the evolutionary process of speciation. James Tytko asked the University of Sheffield's Roger Butlin... Like this podcast? Please help us by <a href="https://www.thenakedscientists.com/donate">supporting the Naked Scientists</a>

How did people in the past find water?

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...