北斯堪的纳维亚北部北方树木的冰川生存
Laura Parducci1, Tina Jørgensen, Mari Mette Tollefsrud
1Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
概括
在斯堪的纳维亚,针树在最后一个冰河时代幸存下来,这挑战了人们对它们在冰盖退后重新殖民的看法. 在挪威湖泊沉积物中,有证据显示古代树的DNA,这表明它们在没有冰的避难所生存.
科学领域:
- 古植物学是古植物学.
- 四分期的帕利诺基学.
- 分子生态学分子生态学
背景情况:
- 主流观点认为,斯堪的纳维亚在最后一次冰河时期没有树木,重新殖民发生在9000年前.
- 在斯堪的纳维亚,在最后一个冰川时期的无冰避难所是假设,但缺乏直接的植物学证据.
研究的目的:
- 调查斯堪的纳维亚在最后一次冰河时期的针叶树的存在和生存情况.
- 挑战斯堪的纳维亚半岛冰川后森林再殖民的既定时间表.
主要方法:
- 对稀有线粒体DNA (mtDNA) 的分析.
- 从湖泊沉积物和花粉中提取的古代DNA的放射性碳测年.
- 在沉积物内核中识别松树和杉树的叶绿体DNA.
主要成果:
- 在挪威西部发现了一种独特的斯堪的纳维亚杉mtDNA单基因型,其频率很高.
- 在Trøndelag湖沉积物中检测到这棵杉叶类型的DNA,可以追溯到大约10,300年前.
- 在挪威西北部的沉积物中鉴定了松树和杉树的DNA,这些沉积物分别可以追溯到大约22,000年前和17,700年前,位于Andøya避难所附近.
结论:
- 针叶树,包括松树和杉树,在斯堪的纳维亚的无冰避难所幸存下来,幸存下来最后的冰期.
- 这些发现需要对当前关于树木生存和分散模式的模型进行修订,以应对过去的气候变化.
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