( ( This energy ) ( then ( ( flows ( to ( ( each ( trophic level ) ) ( via ( a ( food chain ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (DT This) (NN energy)) (ADVP (RB then)) (VP (VBZ flows) (PP (TO to) (NP (NP (DT each) (JJ trophic) (NN level)) (PP (IN via) (NP (DT a) (NN food) (NN chain)))))) (. .)))
This energy then flows to each trophic level via a food chain.
(ROOT (S (NP (NP (NN Loss)) (PP (IN of) (NP (NN energy)))) (VP (VBZ is) (NP (DT the) (NN reason)) (SBAR (IN that) (S (NP (NN food) (NN chain)) (ADVP (RB typically)) (VP (VBZ has) (NP (JJ few) (NNS levels)))))) (. .)))