( ( ( The size ) ( of ( their range ) ) ) ( ( is ( determined ( by ( ( the food ) ( available ( in ( that area ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN size)) (PP (IN of) (NP (PRP$ their) (NN range)))) (VP (VBZ is) (VP (VBN determined) (PP (IN by) (NP (NP (DT the) (NN food)) (ADJP (JJ available) (PP (IN in) (NP (DT that) (NN area)))))))) (. .)))
The size of their range is determined by the food available in that area.
(ROOT (S (NP (NP (DT The) (NN amount)) (PP (IN of) (NP (NP (NN food)) (ADJP (JJ available) (PP (IN in) (NP (DT the) (NN area))))))) (ADVP (RB best)) (VP (VBZ determines) (NP (NP (DT the) (NN number)) (PP (IN of) (NP (NP (NNS wolves)) (SBAR (WHNP (WDT that)) (S (VP (MD can) (VP (VB live) (PP (IN in) (NP (DT an) (NN area))))))))))) (. .)))