《北极地标生物的年代际迁徙物候学与气候变化同步》

  • 来源专题:中国科学院文献情报系统—海洋科技情报网
  • 编译者: liguiju
  • 发布时间:2023-03-06
  • 独角鲸和其他北极鲸类动物寿命相对较长,最长可以超过100年,这些鲸类物种的迁徙物候学的延迟表明,以前被认为不灵活的物种可以在一个生命周期内对气候动态变化做出行为反应。行为可塑性是观察到的物种应对环境变化反应的一个重要驱动因素,因为许多长寿物种不太可能与气候变化保持同步从而表现出进化反应。鉴于许多大型食肉动物的寿命很长,这些反应可能会导致新北极地区的生命面临越来越多的风险。
    动物迁徙以响应季节性环境变化、繁殖演化和趋利避害的需求。尽管预计气候变化会改变动物迁徙,但迄今为止只有少数研究证明了海洋哺乳动物的物候变化。在北极,海洋哺乳动物由于受栖息地影响明显且寿命长,被认为对持续的气候变化最为敏感。长寿是物种进化反应的障碍,长寿物种的迁徙往往主要是应对气候变化的表现。研究人员通过分析加拿大北极地区21年间的卫星跟踪数据,证明了独角鲸秋季迁徙时间呈现出明显延迟。迁徙物候学的监测结果每年都在变化,主要受独角鲸性别和气候影响,说明独角鲸正在采取迁徙策略。人们发现雄性独角鲸会主导离开夏季区域的迁徙,而雌性独角鲸需要抚养幼崽,会在较晚的时候离开。独角鲸每十年在夏季区域停留时间会增加10天,这与该地区受气候影响海冰消失的速度相似。(王琳  编辑)

  • 原文来源:https://www.pnas.org/doi/10.1073/pnas.2121092119
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