按逻辑关系排列下面各段的句子。 A. Secure in its island home, the dodo had lost the power of flight since there were no enemies to fly from. B. The goats ate the undergrowth which provided the dodo with cover dogs and cats hunted and harried the old birds; while pigs grunted their way round the island, eating the eggs and young, and the rats followed behind to finish the feast. C. Man discovered the dodo’s paradise in about 1507, and with him came dodo’s enemies: dogs, cats, pigs, rats and goats. D. The dodo, the ponderous waddling pigeon, inhabited the island of Mauritius. E. The dodo surveyed these new arrivals with an air of innocent interest. F. By 1681, the fat, ungainly and harmless pigeon was extinct. G. Then the slaughter began.