Something very weird goes on in mating assemblies of the White-barred Acraea butterfly - males and females swap roles. Why? And what can it tell us about a secret natural force shaping whole populations of insects? Subscribe to the show to make sure you don't miss any future Wild Episodes, and e-mail your comments, corrections, suggestions or feedback to help make those future episodes better! You can also follow the show on Facebook or Twitter. To support the show, please share on social media, rate and review in your podcast app! Thank you. Show notes, with photos, video and links to lots more information, are available at thewildepisode.com Music Opening & Closing Themes: Running Waters and Acoustic Meditation by Audionautix (Jason Shaw), from audionautix.com. CC BY 3.0. Modified versions of: Headway, modum and periculum by Kai Engel, CC BY 4.0