( ( Since ( life ( first ( ( appeared ( on Earth ) ) ( ( ( 3.5 billion ) years ) ago ) ) ) ) ) ( , ( ( ( many ( new types ) ) ( of organisms ) ) ( ( have evolved ) . ) ) ) )
(ROOT (S (SBAR (IN Since) (S (NP (NN life)) (ADVP (RB first)) (VP (VBD appeared) (PP (IN on) (NP (NNP Earth))) (ADVP (NP (QP (CD 3.5) (CD billion)) (NNS years)) (RB ago))))) (, ,) (NP (NP (JJ many) (JJ new) (NNS types)) (PP (IN of) (NP (NNS organisms)))) (VP (VBP have) (VP (VBN evolved))) (. .)))
Since life first appeared on Earth 3.5 billion years ago, many new types of organisms have evolved.
(ROOT (S (NP (DT The) (JJ first) (VBG living) (NNS cells)) (VP (MD may) (VP (VB have) (VP (VBN evolved) (ADVP (NP (QP (RB around) (CD 4) (CD billion)) (NNS years)) (RB ago))))) (. .)))