( But ( ( when touched ) ( , ( they ( ( release ( ( ( formic acid ) , ) ( ( the ( same chemical ) ) ( that ( ( lends authority ) ( to ( ant ( bites ( and ( bee stings ) ) ) ) ) ) ) ) ) ) . ) ) ) ) )
(ROOT (S (CC But) (SBAR (WHADVP (WRB when)) (S (VP (VBD touched)))) (, ,) (NP (PRP they)) (VP (VBP release) (NP (NP (JJ formic) (NN acid)) (, ,) (NP (NP (DT the) (JJ same) (NN chemical)) (SBAR (WHNP (WDT that)) (S (VP (VBZ lends) (NP (NN authority)) (PP (TO to) (NP (NN ant) (NNS bites) (CC and) (NN bee) (NNS stings))))))))) (. .)))
But when touched, they release formic acid, the same chemical that lends authority to ant bites and bee stings.
(ROOT (S (NP (JJ Formic) (NN acid)) (VP (VBZ is) (VP (VBN found) (PP (IN in) (NP (NP (DT the) (NNS secretions)) (PP (IN of) (NP (JJ stinging) (NNS ants))))))) (. .)))