What love darts reveal about evolution

In this episode, we consider a creature we often don’t think much about—the snail. And not just snails, but their sex lives. Which, as it turns out, is epic. There is persuasion and subterfuge, spaghetti penises and co-copulation. And this very surprising habit—erm kink—of making tiny arrows (actually!) and stabbing each other with them. Known as a “love dart,” these limestone daggers aren’t just a strange trick of nature—they have a deep evolutionary purpose. 

Special thanks to Menno Schilthuizen and Aaron Chase.

EPISODE CREDITS: 
Hosted by - Molly Webster
Reported by - Molly Webster
Produced by - Mona Madgavkar, Annie McEwen, Molly Webster
Sound design contributed by - Mona Madgavkar, Annie McEwen
Fact-checking by - Diane A. Kelly
and Edited by  - Alex Neason

EPISODE CITATIONS:

Videos -  
A love dart being DARTED! (https://zpr.io/rYhLwXhaxQQP)  – Molly has watched this video so many times

Articles - 

• Changes in the reproductive system of the snail Helix aspersa caused by mucus from the love dart. (https://zpr.io/xxjuCcTyiVJV) by Koene JM, Chase R. J Exp Biol.
• The snail's love-dart delivers mucus to increase paternity. By Chase R, Blanchard KC. Proc Biol Sci.
• A love-dart at the heart of sexual conflict in snails (https://zpr.io/X2ANHPaEg5sr)  by Foote C 
  ** This article has an image of eight different love darts, and it’s what Molly shows to Soren in the episode (this image is one of her favorite research finds!) 

Books - 
“Nature’s Nether Regions: What the Sex Lives of Bugs, Birds, and Beasts Tell Us About Evolution, Biodiversity, and Ourselves” (https://zpr.io/ktMvJbZciCdD)  by evolutionary biologist Menno Schilthuizen.

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