Question: when did the first primates appear on earth
[{'answer': '66 million years ago', 'provenance': [{'wikipedia_id': '43535798', 'title': 'Evolution of primates', 'start_paragraph_id': 2, 'start_character': 194, 'end_paragraph_id': 2, 'end_character': 214, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '43535798', 'title': 'Evolution of primates', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 340, 'bleu_score': 0.564151511272119, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6988789515795242844}, 'section': 'Section::::Abstract.'}]}]