( Scientists ( ( believe ( ( ( ( ( the ( first eukaryotes ) ) ( were protists ) ) , ) and ) ( that ( they ( reproduced asexually ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Scientists)) (VP (VBP believe) (SBAR (SBAR (S (NP (DT the) (JJ first) (NNS eukaryotes)) (VP (VBD were) (ADJP (JJ protists))))) (, ,) (CC and) (SBAR (IN that) (S (NP (PRP they)) (VP (VBD reproduced) (ADVP (RB asexually))))))) (. .)))
Scientists believe the first eukaryotes were protists, and that they reproduced asexually.
(ROOT (S (NP (NNS Scientists)) (VP (VBP think) (SBAR (S (NP (NNS protists)) (VP (VBP are) (NP (DT the) (JJS oldest) (NNS eukaryotes)))))) (. .)))