( ( If ( there ( are ( ( mass extinctions ) ( of ( most species ) ) ) ) ) ) ( , ( humans ( ( ( will ( almost certainly ) ) ( be ( the ( only ( primates ( to survive ) ) ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN If) (S (NP (EX there)) (VP (VBP are) (NP (NP (JJ mass) (NNS extinctions)) (PP (IN of) (NP (JJS most) (NNS species))))))) (, ,) (NP (NNS humans)) (VP (MD will) (ADVP (RB almost) (RB certainly)) (VP (VB be) (NP (DT the) (JJ only) (NNS primates) (S (VP (TO to) (VP (VB survive))))))) (. .)))
If there are mass extinctions of most species, humans will almost certainly be the only primates to survive.
(ROOT (S (NP (NNP Human) (NNS actions)) (VP (VBZ is) (ADJP (JJ responsible) (PP (IN for) (NP (NP (DT the) (NN extinction)) (PP (IN of) (NP (NP (NNS hundreds)) (PP (IN of) (NP (NP (NNS species)) (PP (IN of) (NP (NNS birds))))))))))) (. .)))