( ( ( ( ( ( ( Birds ' ) bills ) ( ( are evolutionarily ) ( shaped ( by ( their environment ) ) ) ) ) , ) often ) ( ( ( ( food size ) or ) ( abundance.One example ) ) ( can ( ( ( be ( ( explained ( by ( the fact ) ) ) ( that ( insects ( are ( ( more abundant ) ( -LRB- ( ( ( numbers and ) species ) -RRB- ) ) ) ) ) ) ) ) and ) ( ( get ( bigger ( in ( the tropics ) ) ) ) ( than ( in ( the ( ( more temperate ) regions ) ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (NP (NNP Birds) (POS ')) (NNS bills)) (VP (VBP are) (ADVP (RB evolutionarily)) (VP (VBN shaped) (PP (IN by) (NP (PRP$ their) (NN environment)))))) (, ,) (ADVP (RB often)) (S (NP (NP (NN food) (NN size)) (CC or) (NP (JJ abundance.One) (NN example))) (VP (MD can) (VP (VP (VB be) (VP (VBN explained) (PP (IN by) (NP (DT the) (NN fact))) (SBAR (IN that) (S (NP (NNS insects)) (VP (VBP are) (ADJP (ADJP (RBR more) (JJ abundant)) (PRN (-LRB- -LRB-) (NP (NP (NNS numbers)) (CC and) (NP (NNS species))) (-RRB- -RRB-)))))))) (CC and) (VP (VB get) (NP (NP (JJR bigger)) (PP (IN in) (NP (DT the) (NNS tropics)))) (PP (IN than) (PP (IN in) (NP (DT the) (ADJP (RBR more) (JJ temperate)) (NNS regions)))))))) (. .)))
Birds’ bills are evolutionarily shaped by their environment, often food size or abundance.One example can be explained by the fact that insects are more abundant (numbers and species) and get bigger in the tropics than in the more temperate regions.
(ROOT (S (NP (NP (JJ Many) (NNS species)) (PP (IN of) (NP (NP (NNS birds)) (PP (IN in) (NP (JJ new) (NN england)))))) (VP (VBP fly) (ADVP (RB south) (PP (IN for) (NP (DT the) (NN winter) (NNS months)))) (S (VP (TO to) (VP (VB find) (NP (DT an) (NN environment)) (PP (IN with) (NP (JJR more) (NN food))))))) (. .)))