Benthic foraminiferal assemblage changes during interstadial 4 to 8 in ODP Site 146-893A, Santa Barbara Basin

Benthic foraminiferal assemblages from Santa Barbara Basin exhibit major faunal and ecological switches associated with late Quaternary millennial- to decadal-scale global climate oscillations. Repeated turnovers of entire faunas occurred rapidly (<40-400 yr) without extinction or speciation in conjunction with Dansgaard-Oeschger shifts in thermohaline circulation, ventilation, and climate, confirming evolutionary model predictions of Roy et al. Consistent faunal successions of dysoxic taxa during successive interstadials reflect the extreme sensitivity and adaptation of the benthic ecosystem to the rapid environmental changes that marked the late Quaternary and possibly other transitional intervals in the history of the Earth's ocean-atmosphere-cryosphere system. These data support the hypothesis that broad segments of the biosphere are well adapted to rapid climate change.

圣巴巴拉盆地（Santa Barbara Basin）的底栖有孔虫组合（Benthic foraminiferal assemblages）呈现出显著的动物群与生态转换事件，这些事件与晚第四纪千年至十年尺度的全球气候振荡紧密相关。在丹斯果-奥什格尔旋回（Dansgaard-Oeschger shifts）引发的温盐环流（thermohaline circulation）、大洋通风与气候转变过程中，整个动物群快速发生了重复更替（时长<40~400年），且未伴随物种灭绝或物种形成事件，这验证了Roy等人提出的演化模型预测。在连续的间冰阶（interstadials）中，低氧类群（dysoxic taxa）始终保持一致的动物群演替序列，这反映出底栖生态系统对晚第四纪乃至地球海洋-大气-冰冻圈（ocean-atmosphere-cryosphere system）演化历史中其他潜在过渡阶段所经历的快速环境变化，具有极强的敏感性与适应性。本数据集支持以下假说：生物圈的广泛类群能够良好适应快速气候变化。