( ( ( animal behavior ) ( by reflexes ) ) . )
(ROOT (NP (NP (NN animal) (NN behavior)) (PP (IN by) (NP (NNS reflexes))) (. .)))
animal behavior by reflexes.
(ROOT (S (NP (NNP Reflex) (NNS behaviors)) (VP (VBP are) (NP (NP (DT the) (RB only) (JJ innate) (NNS behaviors)) (PP (IN in) (NP (NNS humans))))) (. .)))