Preemptive Defensive Self‑Sacrifice by Ant Workers Tofilski, Adam ; Couvillon, Margaret J. ; Evison, Sophie E. F. ; Helanterä, Heikki ; Robinson, Elva J. H. ; Ratnieks, Francis L. W. Abstract Publication: American Naturalist Pub Date: November 2008 DOI: 10.1086/591688 Bibcode: 2008ANat..172E.239T