A WOOD-FALL ASSOCIATION FROM LATE EOCENE DEEP-WATER SEDIMENTS OF WASHINGTON STATE, USA
A WOOD-FALL ASSOCIATION FROM LATE EOCENE DEEP-WATER SEDIMENTS OF WASHINGTON STATE, USA
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美国华盛顿州始新世晚期深水沉积物中的树木倒塌协会
DOI：
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发表时间：
2006
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影响因子：
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通讯作者：
J. Goedert
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作者：
S. Kiel;J. Goedert
摘要在美国华盛顿州的林肯溪组的始新世晚期深水沉积物中发现了类似于现今深海木材福尔斯上发现的化石碎片和相关的物种丰富的无脊椎动物组合。这个组合是已知最早的复杂深海生物群落，以腐烂的木材为主要营养来源。发现的495个化石（不包括有孔虫）属于21个种; 7个种直接依赖木材，要么通过摄入木材，要么通过摄食食木微生物;这些物种也是最丰富的。7个物种是捕食者或食腐动物，最有可能被依赖木材的物种所吸引。其余7个物种代表食肉动物，碎屑饲养者，和悬浮饲养者，可能或可能没有关系的木材下降或其动物群。所有物种都有底栖生活方式，没有伪浮游生物类群，表明木材到达深海海底后才开始殖民。依赖木材的物种属于今天在深海中填补同一生态位的类群，这表明现代的伐木生态系统至少在始新世晚期已经进化。有没有统一或专业化的恢复类群之间的扩散策略，而反映了它们所属的系统发育组。这里所描述的木瀑布组合与化石鲸鱼福尔斯和冷泉共有几个科，但物种很少，这种情况也可以在这些生态系统的现代例子中观察到。
Abstract Fossil wood fragments and an associated species-rich invertebrate assemblage, analogous to those found on wood falls in the deep sea today, were found in late Eocene deep-water sediments of the Lincoln Creek Formation in Washington State, United States. This assemblage is the earliest known complex deep-sea biologic community based on decaying wood as its primary source of nutrients. The 495 recovered fossils (exclusive of foraminiferans) belong to 21 species; 7 species relied directly on the wood, either by ingesting it or by feeding on xylophagous microbes; these species are also the most abundant. Seven species were predators or scavengers that were most likely attracted by the wood-dependent species. The remaining seven species represent predators, detritus feeders, and suspension feeders that may or may not have had a relation to the wood fall or its fauna. All species had a benthic mode of life, and pseudoplanktonic taxa are absent, indicating that the colonization of the wood began only once it had arrived on the deep-sea floor. The wood-dependent species belong to taxa that fill the same ecologic niche in the deep sea today, indicating that the modern wood-fall ecosystem had evolved at least by late Eocene time. There is no uniformity or specialization of dispersal strategies among the recovered taxa; they rather reflect those of the phylogenetic group to which they belong. The wood-fall assemblage described here shares several families with fossil whale falls and cold seeps but very few species, a condition that can also be observed at modern examples of these ecosystems.