( ( ( ( ( 1 -RRB- ) ( Animals ( follow ( food resources ) ) ) ) - ) ( birds ( ( move south ) ( when ( food ( becomes ( scarce ( in winter ) ) ) ) ) ) ) ) . )
(ROOT (S (S (LST (LS 1) (-RRB- -RRB-)) (NP (NNS Animals)) (VP (VBP follow) (NP (NN food) (NNS resources)))) (: -) (S (NP (NNS birds)) (VP (VBP move) (ADVP (RB south)) (SBAR (WHADVP (WRB when)) (S (NP (NN food)) (VP (VBZ becomes) (ADJP (JJ scarce) (PP (IN in) (NP (NN winter))))))))) (. .)))
1) Animals follow food resources - birds move south when food becomes scarce in winter.
(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))))))) (. .)))