( ( environmental changes ) ( ( can ( lead ( to ( ( increased access ) ( to ( certain foods ) ) ) ) ) ) ; ) )
(ROOT (S (NP (JJ environmental) (NNS changes)) (VP (MD can) (VP (VB lead) (PP (TO to) (NP (NP (VBN increased) (NN access)) (PP (TO to) (NP (JJ certain) (NNS foods))))))) (: ;)))
environmental changes can lead to increased access to certain foods;
(ROOT (S (NP (NP (DT A) (NN change)) (PP (IN of) (NP (NP (NN season)) (CC and) (NP (JJR less) (NN food))))) (ADVP (RB usually)) (VP (VB cause) (S (NP (JJ certain) (NNS animals)) (VP (TO to) (VP (VB migrate))))) (. .)))
A change of season and less food usually cause certain animals to migrate.