【明報專訊】In the Galapagos islands, there once lived thousands of huge tortoises. They are land animals who floated to these distant isles millions of years ago. Here they learned to adapt to their new environment and ate the local cactus and even the toxic fruit of a native plant which resembled a small golden apple. As the islands were home to mainly birds and iguanas, the tortoises had no natural enemies. So they slowly grew to be enormous and easily lived to be over a hundred. Each island had its own particular type: some had very long necks to reach up to get fruit and leaves, some had a high domed（拱形）shell, some had a flattened（平坦的）shell.