( ( Distinguish ( between ( gradualism ( and ( punctuated equilibrium ) ) ) ) ) . )
(ROOT (S (VP (VB Distinguish) (PP (IN between) (NP (NN gradualism) (CC and) (NN punctuated) (NN equilibrium)))) (. .)))
Distinguish between gradualism and punctuated equilibrium.
(ROOT (S (NP (NNP Darwin)) (VP (VBD believed) (PP (IN in) (NP (NN gradualism)))) (. .)))