Many other species have multiple partners, but are humans meant for monogamy? Plus we ask, do flies have a super sense of smell? Like this podcast? Please help us by <a href="https://www.thenakedscientists.com/donate">supporting the Naked Scientists</a>

Will our increasing human population cause a water shortage on Earth?

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...