( ( According ( to ( the ( competitive ( exclusion principle ) ) ) ) ) ( , ( it ( ( ( is ( impossible ( for ( two species ) ) ) ) ( to ( ( occupy ( the ( same niche ) ) ) ( for ( ( an ( extended period ) ) ( of time ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (VBG According) (PP (TO to) (NP (DT the) (JJ competitive) (NN exclusion) (NN principle)))) (, ,) (NP (PRP it)) (VP (VBZ is) (ADJP (JJ impossible) (PP (IN for) (NP (CD two) (NNS species)))) (S (VP (TO to) (VP (VB occupy) (NP (DT the) (JJ same) (NN niche)) (PP (IN for) (NP (NP (DT an) (JJ extended) (NN period)) (PP (IN of) (NP (NN time))))))))) (. .)))
According to the competitive exclusion principle, it is impossible for two species to occupy the same niche for an extended period of time.
(ROOT (S (NP (JJ Competive) (NN exclusion) (NN princple)) (VP (VBZ explains) (SBAR (WHADVP (WRB why)) (S (NP (CD two) (JJ different) (NNS species)) (VP (MD can) (RB not) (VP (VB occupy) (NP (NP (DT the) (JJ same) (NN niche)) (PP (IN in) (NP (DT the) (JJ same) (NN place)))) (PP (IN for) (ADJP (RB very) (JJ long)))))))) (. .)))