Gehling James G, Droser Mary L
South Australian Museum and Sprigg Geobiology Centre, University of Adelaide, North Terrace, Adelaide, South Australia 5000, Australia.
Department of Earth Sciences, University of California, Riverside, CA 92521, U.S.A.
Emerg Top Life Sci. 2018 Sep 28;2(2):213-222. doi: 10.1042/ETLS20170166.
Predation is one of the most fundamental ecological and evolutionary drivers in modern and ancient ecosystems. Here, we report the discovery of evidence of the oldest scavenging of shallowly buried bodies of iconic soft-bodied members of the Ediacara Biota by cryptic seafloor mat-burrowing animals that produced the furrow and levee trace fossil, Helminthoidichnites isp. These mat-burrowers were probably omnivorous, stem-group bilaterians that largely grazed on microbial mats but when following mats under thin sands, they actively scavenged buried Dickinsonia, Aspidella, Funisia and other elements of the Ediacara Biota. These traces of opportunistic scavengers of dead animals from the Ediacaran of South Australia represent a fundamental ecological innovation and a possible pathway to the evolution of macrophagous predation in the Cambrian. While the Ediacaran oceans may have had oxygen levels too low to support typical large predators, the Helminthoidichnites maker lived in and grazed on microbial mats, which may have provided a localized source of oxygen.
捕食是现代和古代生态系统中最基本的生态和进化驱动力之一。在此，我们报告发现了有证据表明，一种能产生沟渠和堤坝痕迹化石——似蠕虫迹（Helminthoidichnites isp）的隐匿性海底席状潜穴动物，对埃迪卡拉生物群标志性软躯体成员的浅埋尸体进行了最古老的食腐行为。这些席状潜穴动物可能是杂食性的干群两侧对称动物，主要以微生物席为食，但当在薄沙下追踪席状物时，它们会主动 scavenged 埋藏的狄更逊水母（Dickinsonia）、阿斯皮德迹属（Aspidella）、Funisia 以及埃迪卡拉生物群的其他成员。这些来自南澳大利亚埃迪卡拉纪的动物尸体机会主义食腐者的痕迹，代表了一项重要的生态创新，以及寒武纪大型捕食行为进化的一条可能途径。虽然埃迪卡拉纪海洋的氧气水平可能过低，无法支持典型的大型捕食者，但似蠕虫迹制造者生活在微生物席中并以其为食，微生物席可能提供了局部的氧气来源。 （注：原文中“scavenged”未翻译完整，推测可能是“清理、搜寻（尸体等以供食用）”之类意思，这里保留英文供参考完整理解语境）
