Konrad Wothe / Red Wood Ant (Formica rufa) colony reacting in defensive behavior by spraying formic acid from a gland in rear of their abdomens, Sweden

Stephen Dalton / Close up of Orb Weaver Spider (Tetragnathidae) abdomen showing spinnerets and thread being controlled by legs. UK.

Nick Upton / Worker Honey ants with abdomens swollen with honey {Myrmecocystus mimicus} USA

Nick Upton / Worker Honey ants with abdomens swollen with honey {Myrmecocystus mimicus} USA

Mark Moffett / Tarantula (Pseudotheraphosa sp) surrounded by a cloud of barbed toxic hairs which it breaks off by brushing their abdomens with hind legs as a defensive move, Venezuela