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Some of this ice age dung was found beneath the skull1 in the Aucilla. The dung contained plant remains2 that tell us what the mastodon was browsing3 on 13,000 years ago or more—a mixture of trees and grasses.
This suggests that ice age Florida was drier than it is today—a mix of woodlands and savanna4 rather than swamps. And mastodon teeth found in the Aucilla held a more important revelation. The enamel5 contains chemical signatures of a local soil, passed by the plants the mastodons ate. But some of the chemicals found in the Aucilla teeth could only have come from soil hundreds of miles further north. The inescapable conclusion is that these mastodons migrated, making a round trip of more than 400 miles every year. And since their dung also contains remains of summer fruits from the Aucilla region, they must have travelled north for the winter.
The question is, why? Why leave a place which as we have seen was abundant with food and a refuge from the cold? And why go north for the winter when most migrants move south? Perhaps the present climate can provide a clue.
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1 skull | |
n.头骨;颅骨 | |
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2 remains | |
n.剩余物,残留物;遗体,遗迹 | |
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3 browsing | |
v.吃草( browse的现在分词 );随意翻阅;(在商店里)随便看看;(在计算机上)浏览信息 | |
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4 savanna | |
n.大草原 | |
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5 enamel | |
n.珐琅,搪瓷,瓷釉;(牙齿的)珐琅质 | |
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6 peculiar | |
adj.古怪的,异常的;特殊的,特有的 | |
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7 seasonal | |
adj.季节的,季节性的 | |
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8 quirk | |
n.奇事,巧合;古怪的举动 | |
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