Question: when did amphibians begin to colonize land as the first terrestrial vertebrates
[{'answer': 'the late Devonian era'}, {'provenance': [{'wikipedia_id': '46333271', 'title': 'Vertebrate land invasion', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 603, 'bleu_score': 0.9505764710553931, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8141434051232006788}, 'section': 'Section::::Abstract.'}]}]