( ( ( In ( ( ( eusocial and ) cooperatively ) ( breeding animals ) ) ) ( ( most ( non-reproducing helpers ) ) ( ( ( engage ( in ( kin selection ) ) ) , ) ( ( enhancing ( their ( own ( inclusive fitness ) ) ) ) ( by ( ensuring ( ( the survival ) ( of offspring ) ) ) ) ) ) ) ) ( they ( ( are ( closely ( related to ) ) ) . ) ) )
(ROOT (S (S (PP (IN In) (NP (ADJP (JJ eusocial) (CC and) (JJ cooperatively)) (NN breeding) (NNS animals))) (NP (RBS most) (JJ non-reproducing) (NNS helpers)) (VP (VBP engage) (PP (IN in) (NP (NN kin) (NN selection))) (, ,) (S (VP (VBG enhancing) (NP (PRP$ their) (JJ own) (NN inclusive) (NN fitness)) (PP (IN by) (S (VP (VBG ensuring) (NP (NP (DT the) (NN survival)) (PP (IN of) (NP (NN offspring))))))))))) (NP (PRP they)) (VP (VBP are) (ADJP (RB closely) (VBN related) (PP (TO to)))) (. .)))
In eusocial and cooperatively breeding animals most non-reproducing helpers engage in kin selection, enhancing their own inclusive fitness by ensuring the survival of offspring they are closely related to.
(ROOT (S (NP (DT The) (NN term) (NN fitness)) (VP (VBZ describes) (NP (NP (DT the) (JJ overall) (NN ability)) (PP (IN of) (NP (DT an) (NN animal) (S (VP (TO to) (VP (VB survive) (CC and) (VB produce) (NP (NN offspring))))))))) (. .)))