Uploaded October 2016 | Updated September 2026, 2 weeks ago

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Produced on site at New Scientist Live 2016! This was a question from the #MendeleyWall, a giant wall in the Mendeley booth where people wrote down the questions they had for science.

Illustrated by Claudia Stocker (vividbiology.com), edited by Lisa Dennison (sciencesketches.org), background music by Jeff Woodruff (sciencesketches.org).