Rapid response of a marine mammal species to holocene climate and habitat change.
Rapid response of a marine mammal species to holocene climate and habitat change.
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DOI：
10.1371/journal.pgen.1000554
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发表时间：
2009-07
期刊：
影响因子：
4.5
通讯作者：
Hoelzel AR
中科院分区：
文献类型：
--
作者：
de Bruyn M;Hall BL;Chauke LF;Baroni C;Koch PL;Hoelzel AR
环境变化推动了决定物种内部和物种之间多样性的人口和进化过程。在变化期间跟踪这些过程可以揭示种群形成的机制，并提供关于应对未来潜在影响的预测数据，包括人为气候变化造成的影响。在这里，我们将展示一个高度移动的海洋物种如何应对新的繁殖栖息地的获得和丧失。南象海豹Mirounga leonina的遗骸是在南极洲罗斯海的维多利亚陆地海岸（VLC）沿着发现的，距离麦格理岛（MQ）现存最近的繁殖地2，500公里。这个栖息地是在罗斯海海湾7，500 - 8，000 cal YBP的接地冰盖撤退后释放的，并且在MQ殖民地的现代觅食游览范围内。使用古老的mtDNA和结合模型，我们追踪了现已灭绝的VLC殖民地的人口动态以及与现存繁殖地点之间的联系。我们在VLC种群中发现了一个明显的扩张信号，大约8，000 YBP，然后是从VLC方向迁移，并在10，000 YBP失去多样性，当时海冰被认为已经扩张。我们的数据表明，VLC海豹最初来自MQ，一些在VLC栖息地消失后返回那里，大约7,000年后。我们跟踪的创始人灭绝动态的人口从成立到灭绝的全新世气候变化的背景下，目前的证据表明，一个出乎意料的多样性，分化的繁殖人口成立后不久，从一个遥远的来源人口栖息地成为可用。为了了解生物多样性是如何产生和维持的，我们需要了解种群形成和分化的过程。物种内的自然变异通常在种群之间分配，这有时构成物种形成事件的基础。在种群水平上建立新变异的一个机制是通过对新出现的栖息地的反应。在这里，我们使用来自古代DNA的数据来展示当新的繁殖栖息地获得时，海象种群如何反应，然后在大约7,000年的时间里失去。我们发现，海豹迅速利用新的繁殖栖息地，远离最近的现存繁殖地，并建立了一个高度多样化和遗传分化的人口在几代人的问题。关键因素可能是丰富的当地食物资源和广泛的物理栖息地，允许快速扩张后，最初的创始人事件和女性的趋势，以返回到每年的繁殖地点在这个物种。跟踪历史种群的创始人灭绝动态提供了对未来环境变化的可能影响的见解。这是我们努力减轻人为变化影响的一个重要工具。
Environmental change drives demographic and evolutionary processes that determine diversity within and among species. Tracking these processes during periods of change reveals mechanisms for the establishment of populations and provides predictive data on response to potential future impacts, including those caused by anthropogenic climate change. Here we show how a highly mobile marine species responded to the gain and loss of new breeding habitat. Southern elephant seal, Mirounga leonina, remains were found along the Victoria Land Coast (VLC) in the Ross Sea, Antarctica, 2,500 km from the nearest extant breeding site on Macquarie Island (MQ). This habitat was released after retreat of the grounded ice sheet in the Ross Sea Embayment 7,500–8,000 cal YBP, and is within the range of modern foraging excursions from the MQ colony. Using ancient mtDNA and coalescent models, we tracked the population dynamics of the now extinct VLC colony and the connectivity between this and extant breeding sites. We found a clear expansion signal in the VLC population ∼8,000 YBP, followed by directional migration away from VLC and the loss of diversity at ∼1,000 YBP, when sea ice is thought to have expanded. Our data suggest that VLC seals came initially from MQ and that some returned there once the VLC habitat was lost, ∼7,000 years later. We track the founder-extinction dynamics of a population from inception to extinction in the context of Holocene climate change and present evidence that an unexpectedly diverse, differentiated breeding population was founded from a distant source population soon after habitat became available. In order to understand how biodiversity is generated and maintained over time, we need to understand the process by which populations form and diverge. Natural variation within species is typically partitioned among populations, which sometimes forms the basis for speciation events. One mechanism for the establishment of novel variation at the population level is through a response to emerging habitat. Here we use data from ancient DNA to show how elephant seal populations responded when new breeding habitat was gained and then lost over the course of approximately 7,000 years. We show that the seals quickly took advantage of newly available breeding habitat, far from the nearest extant breeding site, and that a highly diverse and genetically differentiated population was established over a matter of generations. The key factors were likely the abundant local food resource and extensive physical habitat that allowed rapid expansion after the initial founder event and a tendency for females to return to annual breeding sites in this species. Tracking the founder-extinction dynamics of historical populations provides insight into the likely implications of future environmental change. This is an important tool in our efforts to mitigate the impact of human-induced change.
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影响因子：
56.9
作者：
Fabiani, A;Hoelzel, AR;Muelbert, MMC
通讯作者：
Muelbert, MMC
影响因子：
3.7
作者：
Depaulis F;Orlando L;Hänni C
通讯作者：
Hänni C
影响因子：
2.3
作者：
BARONI, C;OROMBELLI, G
通讯作者：
OROMBELLI, G
影响因子：
56.9
作者：
Conway, H;Hall, BL;Waddington, ED
通讯作者：
Waddington, ED
影响因子：
2.4
作者：
Fabiani, A;Galimberti, F;Hoelzel, AR
通讯作者：
Hoelzel, AR