Faculty of Earth Sciences, Laboratory of Palaeontology and Stratigraphy, University of Silesia in Katowice, Będzińska 60, 41-200, Sosnowiec, Poland.
Faculty of Geology, Department of Historical, Regional Geology and Paleontology, University of Warsaw, Żwirki i Wigury93, 02-089, Warszawa, Poland.
Sci Rep. 2024 Aug 2;14(1):17932. doi: 10.1038/s41598-024-67687-2.
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.
捕食驱动的中生代海洋革命（MMR）被认为自中生代晚期以来导致了许多浅海无脊椎动物的水深分布发生了巨大变化。例如，有柄海百合——海百合目（Isocrinida）在浅海环境中经历了显著的衰退，如今它们仅限于深海环境（水深 100 米以下）。然而，这种转变的时间和同步性是一个有争议的问题。有人提出，MMR 的发生时间延迟，以及古近纪在南大洋向逆行、低捕食群落结构的转变。特别是，最近来自南半球的数据表明，海百合目的环境限制在深海环境中可能发生在南极和澳大利亚周围的始新世末期，以及新西兰的早中新世晚期。在这里，我们报告了中中新世波兰（北半球，中副特提斯海）近海浅海相中有柄海百合目异常出现的情况。因此，在全球范围内，这是浅海有柄海百合目最年轻的记录。这一发现表明，一些残余的有柄海百合目可能在中中新世就已经能够生活在浅水环境中，并进一步证实，海百合目的水深限制在全球范围内不是同步的。
