This is Scientific American's 60-second Science, I'm Susanne Bard.Around 100,000 years ago, in what is now Italy,our Neandertal cousins waded out into the shallow coastal waters of the Mediterranean Sea in search of clams.They grabbed the mollusks from the seafloor and perhaps even dived for them in deeper water.And they also simply collected clams from the beach. But the creatures weren't just food.In a recent study, University of Colorado, Boulder, archaeologist Paola Villa and her team reportthat Neandertals modified the clams' hard shells into tools for cutting and scraping.The clam-derived implements were found inside the Grotta dei Moscerini, a coastal cave that was first rediscovered around 85 years ago.By examining wear and tear on the shells,the researchers determined that about 75 percent of the tool source material had been found dead on the beach.These shells had been worn down from being battered by waves and sand.But the remaining shells were smooth and shiny, indicating that the clams were still alive on the seafloor when they were gathered.These shells were also thicker and therefore might have made more durable tools.So even though gathering clams underwater took more work than picking them up on the beach, the effort may have been worth it.Also found in the Grotta dei Moscerini were pumice stones from volcanic eruptions that had occurred to the south of the site.
这里是科学美国人――60秒科学系列，我是苏珊娜・巴德。大约10万年前，在如今的意大利，我们的尼安德特人表亲涉入地中海浅滩水域，寻找蛤蜊。他们捕获海床上的这些软体动物，甚至可能为此潜入深水。他们也会收集海滩上的蛤蜊。但这些生物对他们来说并不仅仅是食物。在最近的一项研究中，科罗拉多大学博尔德分校的考古学家保拉・维拉及其团队报告称，尼安德特人会将蛤蜊的硬壳改造成切割和刮削的工具。这些用蛤蜊壳制造的工具在Grotta dei Mosserini洞中被发现，这个海蚀洞在约85年前首次被再发现。通过检查贝壳的磨损情况，研究人员判定，这些工具的原始材料中，有约75%被发现时已经死在海滩上。这些贝壳因为受到海浪和沙子的侵蚀而磨损。但剩下的贝壳却光滑发亮，这说明采集时这些蛤蜊还活在海床上。这些壳还比较厚，因此可能制造出更耐用的工具。因此，尽管在水下采集蛤蜊比在海滩上采集蛤蜊更费力，但这一努力可能是值得的。在Grotta dei Mosserini洞中还发现了一些浮石，它们是该地南边火山喷发的产物。
