( ( ( ( ( ( Their calls ) ( ( varied ( from ( very low ) ) ) ( to ( ( very high ) frequencies ) ) ) ) , ) but ) ( ( each species ) ( seemed ( to ( have ( ( its ( own ( `` ( niche '' ) ) ) ) ( on ( the spectrum ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (PRP$ Their) (NNS calls)) (VP (VBD varied) (PP (IN from) (ADJP (RB very) (JJ low))) (PP (TO to) (NP (ADJP (RB very) (JJ high)) (NNS frequencies))))) (, ,) (CC but) (S (NP (DT each) (NNS species)) (VP (VBD seemed) (S (VP (TO to) (VP (VB have) (NP (NP (PRP$ its) (JJ own) (`` ``) (NN niche) ('' '')) (PP (IN on) (NP (DT the) (NN spectrum))))))))) (. .)))
Their calls varied from very low to very high frequencies, but each species seemed to have its own &quot;niche&quot; on the spectrum.
(ROOT (S (NP (DT Each) (NNS species)) (VP (VBZ has) (NP (NP (DT a) (JJ particular) (NN way)) (PP (IN of) (S (VP (VBG making) (NP (NP (DT a) (NN living)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ is) (VP (VBN called) (NP (PRP$ its) (NN niche)))))))))))) (. .)))
Each species has a particular way of making a living, which is called its niche.