For the second part of our hygiene series, we manage to cover the full range of human bodily needs. Michael walks through the history of toilets and waste removal and Katie talks about all things teeth.

• Apologies about the audio quality - we're still working through some mic issues.

Toilets

History of Poop

NASA Space Waste Guidelines

Poop Researchers

Invention of Toilet Paper

Best Way to Wipe

Queer Toilet History

Toothbrushes

History of Dentistry

Oral Hygiene Timeline

Chewing Stick Research