( ( The ( external skeleton ) ) ( ( ( imposes limits ) ( ( ( ( on ( ( the ( maximum size ) ) ( of ( an arthropod ) ) ) ) , ) especially ) ( in ( those ( that ( live ( on land ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ external) (NN skeleton)) (VP (VBZ imposes) (NP (NNS limits)) (PP (PP (IN on) (NP (NP (DT the) (JJ maximum) (NN size)) (PP (IN of) (NP (DT an) (NN arthropod))))) (, ,) (RB especially) (PP (IN in) (NP (NP (DT those)) (SBAR (WHNP (WDT that)) (S (VP (VBP live) (PP (IN on) (NP (NN land)))))))))) (. .)))
The external skeleton imposes limits on the maximum size of an arthropod, especially in those that live on land.
(ROOT (S (NP (NP (DT The) (NN majority)) (PP (IN of) (NP (NNS arthropods)))) (VP (VBP live) (PP (IN on) (NP (NN land)))) (. .)))