( Evolution ( ( is ( ( the ( genetic change ) ) ( in ( ( ( ( a population ) ( of ( organisms ( over time ) ) ) ) , ) ( produced ( by ( ( the ( integrating agencies ) ) ( of ( natural ( ( selection and ) variation ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Evolution)) (VP (VBZ is) (NP (NP (DT the) (JJ genetic) (NN change)) (PP (IN in) (NP (NP (DT a) (NN population)) (PP (IN of) (NP (NP (NNS organisms)) (PP (IN over) (NP (NN time))))) (, ,) (VP (VBN produced) (PP (IN by) (NP (NP (DT the) (JJ integrating) (NNS agencies)) (PP (IN of) (NP (JJ natural) (NN selection) (CC and) (NN variation)))))))))) (. .)))
Evolution is the genetic change in a population of organisms over time , produced by the integrating agencies of natural selection and variation.
(ROOT (S (NP (NP (NNP Theevolution)) (PP (IN by) (NP (JJ natural) (NN selection) (NN theory)))) (VP (VBZ explains) (SBAR (WHADVP (WRB how)) (S (NP (NP (NNS populations)) (PP (IN of) (NP (NNS organisms)))) (VP (MD can) (VP (VB change) (PP (IN over) (NP (NN time)))))))) (. .)))