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1·Another oceanic resident, the quahog clam (Arctica islandica), is thought to be one of the longest lived metazoans of all.

另一位海洋居民—圆蛤被认为是世界上最长寿的后生动物。

2·This is the only season when tourist operations are possible in Arctica. All other time makes trips to the North Pole too risky due to weather conditions.

这是唯一适合北极旅行的季节，其他时间由于天气原因都太冒险。