PDF(Pubmed)
Abstract：
The predation-driven Mesozoic marine revolution (MMR) is believed to have induced a dramatic change in the bathymetric distribution of many shallow marine invertebrates since the late Mesozoic. For instance, stalked crinoids - isocrinids (Isocrinida) have undergone a striking decline in shallow-sea environments and today they are restricted to deep-sea settings (below 100 m depth). However, the timing and synchronicity of this shift are a matter of debate. A delayed onset of MMR and/or shifts to a retrograde, low-predation community structure during the Paleogene in the Southern Ocean were invoked. In particular, recent data from the Southern Hemisphere suggest that the environmental restriction of isocrinids to the deep-sea settings may have occurred at the end of the Eocene around Antarctica and Australia, and later in the early Miocene in New Zealand. Here, we report the anomalous occurrence of the isocrinids in shallow nearshore marine facies from the middle Miocene of Poland (Northern Hemisphere, Central Paratethys). Thus, globally, this is the youngest record of shallow-sea stalked crinoids. This finding suggests that some relict stalked crinoids may have been able to live in the shallow-water environments by the middle Miocene, and further confirms that the depth restriction of isocrinids to offshore environments was not synchronous on a global scale.
摘要：
自晚中生代以来，捕食驱动的中生代海洋革命（MMR）被认为已引起许多浅海无脊椎动物的测深分布发生了巨大变化。例如,在浅海环境中，有茎的海百合-等分线（Isocrinida）经历了惊人的下降，如今，它们仅限于深海环境（深度低于100m）。然而,这种转变的时机和同步性是一个争论的问题。MMR的延迟发作和/或转变为逆行，调用了南大洋古近纪期间的低捕食群落结构。特别是,来自南半球的最新数据表明，对深海环境的等分线的环境限制可能发生在南极洲和澳大利亚周围的始新世末期，后来在新西兰的早期。这里,我们报告了从波兰的中新世（北半球，CentralParatethys）。因此，全球,这是最年轻的浅海茎类海百合的记录。这一发现表明，一些残存的茎类海百合可能已经能够在上世纪中期生活在浅水环境中，并进一步证实，在全球范围内，对近海环境的深度限制并不同步。
