( ( Animals ( which ( live ( on ( the benthos ) ) ) ) ) . )
(ROOT (FRAG (NP (NP (NNS Animals)) (SBAR (WHNP (WDT which)) (S (VP (VBP live) (PP (IN on) (NP (DT the) (NNS benthos))))))) (. .)))
Animals which live on the benthos .
(ROOT (S (NP (NP (VBG Living) (NNS things)) (PP (IN on) (NP (DT the) (NN ocean) (NN floor)))) (VP (VBP are) (VP (VBN known) (PP (IN as) (NP (NNS benthos))))) (. .)))
Living things on the ocean floor are known as benthos.