( ( ( ( ( Populations and ) ecosystems ) ( A population ) ) ( of ( an organism ) ) ) ( ( ( is simply ) ( ( a group ) ( of ( ( that organism ) ( living ( in ( ( the ( same place ) ) ( at ( the ( same time ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NP (NNS Populations) (CC and) (NNS ecosystems)) (NP (DT A) (NN population))) (PP (IN of) (NP (DT an) (NN organism)))) (VP (VBZ is) (ADVP (RB simply)) (NP (NP (DT a) (NN group)) (PP (IN of) (NP (NP (DT that) (NN organism)) (VP (VBG living) (PP (IN in) (NP (NP (DT the) (JJ same) (NN place)) (PP (IN at) (NP (DT the) (JJ same) (NN time)))))))))) (. .)))
Populations and ecosystems A population of an organism is simply a group of that organism living in the same place at the same time.
(ROOT (S (NP (PRP You)) (VP (VBP call) (NP (NP (DT a) (NN group)) (PP (IN of) (NP (NP (NNS organisms)) (PP (IN of) (NP (DT the) (JJ same) (NN species)))))) (SBAR (IN that) (S (VP (VBP live) (PP (IN in) (NP (DT the) (JJ same) (NN area)))) (NP (DT a) (-LRB- -LRB-) (NN n) (-RRB- -RRB-) (NN population))))) (. .)))