Animals Armed With Lethal Weapons


To learn more about this, read the abstracts of these two papers:

Contests With Deadly Weapons: Telson Sparring in Mantis Shrimp (Stomatopoda)
Green, P. A., & Patek, S. N. (2015). Biology Letters, 11(9). 

Ritualized Fighting and Biological Armor: The Impact Mechanics of the Mantis Shrimp's Telson
Taylor, J. R. A., & Patek, S. N. (2010). Journal of Experimental Biology, 213(20), 3496-3504.