( ( As ( ( the population ) grows ) ) ( , ( ( competition ( for food ) ) ( also ( grows . ) ) ) ) )
(ROOT (S (SBAR (IN As) (S (NP (DT the) (NN population)) (VP (VBZ grows)))) (, ,) (NP (NP (NN competition)) (PP (IN for) (NP (NN food)))) (ADVP (RB also)) (VP (VBZ grows)) (. .)))
As the population grows, competition for food also grows.
(ROOT (S (SBAR (IN As) (S (NP (DT the) (NN population)) (VP (VBZ grows)))) (, ,) (NP (NP (NN competition)) (PP (IN for) (NP (NN food)))) (VP (VBZ grows)) (. .)))