( ( Without macroevolution ) ( , ( evolution ( ( ( does not ) occur ) . ) ) ) )
(ROOT (S (PP (IN Without) (NP (NN macroevolution))) (, ,) (NP (NN evolution)) (VP (VBZ does) (RB not) (VP (VB occur))) (. .)))
Without macroevolution, evolution does not occur.
(ROOT (S (NP (NNP Macroevolution)) (VP (VBZ happens) (SBAR (WHADVP (WRB when)) (S (NP (NP (NNS forces)) (PP (IN of) (NP (NN evolution)))) (VP (VBP work) (PP (IN over) (NP (NP (DT a) (JJ long) (NN period)) (PP (IN of) (NP (NN time))))))))) (. .)))