( ( ( ( ( Pikaia ( appears ( to ( have ( a proto-notochord ) ) ) ) ) , ) and ) ( notochords ( ( ( are ( present ( in ( ( several ( basal chordates ) ) ( such ( as ( Haikouella ( , ( Haikouichthys ( , ( and Myllokunmingia ) ) ) ) ) ) ) ) ) ) ) , ) ( all ( from ( the Cambrian ) ) ) ) ) ) . )
(ROOT (S (S (NP (NNP Pikaia)) (VP (VBZ appears) (S (VP (TO to) (VP (VB have) (NP (DT a) (NN proto-notochord))))))) (, ,) (CC and) (S (NP (NNS notochords)) (VP (VBP are) (ADJP (JJ present) (PP (IN in) (NP (NP (JJ several) (JJ basal) (NNS chordates)) (PP (JJ such) (IN as) (NP (NNP Haikouella) (, ,) (NNP Haikouichthys) (, ,) (CC and) (NNP Myllokunmingia)))))) (, ,) (ADVP (RB all) (PP (IN from) (NP (DT the) (NNP Cambrian)))))) (. .)))
Pikaia appears to have a proto-notochord, and notochords are present in several basal chordates such as Haikouella, Haikouichthys, and Myllokunmingia, all from the Cambrian.
(ROOT (S (NP (NNS Chordates)) (VP (VBP include) (NP (NP (NNS vertebrates) (CC and) (NNS invertebrates)) (SBAR (WHNP (WDT that)) (S (VP (VBP have) (NP (DT a) (NN notochord))))))) (. .)))