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Paleobiological and paleoecological interpretations rely on constraining the temporal resolution of the fossil record. The taphonomic clock, that is, a correlation between the alteration of skeletal material and its age, is an approach for quantifying time-averaging scales. We test the taphonomic clock hypothesis for marine demersal and pelagic fish otoliths from a 10–40 m depth transect on the Mediterranean siliciclastic Israeli shelf by radiocarbon dating and taphonomic scoring. Otolith ages span the last ~8000 yr, with considerable variation in median and range along the transect. Severely altered otoliths, contrary to pristine otoliths, are likely to be older than 1000 yr. For pelagic fish otoliths, at 30 m depth, taphonomic degradation correlates positively with postmortem age. In contrast, no correlation occurs for demersal fishes at 10 and 30 m depth, mostly because of the paucity of very young pristine (<150 yr) otoliths, possibly due to a drop in production over the last few centuries. Contrary to molluscan and brachiopod shells, young otoliths at these depths are little affected and do not show a broad spectrum of taphonomic damage, because those that derive from predation are excreted in calcium- and phosphate-rich feces forming an insoluble crystallic matrix that increases their preservation potential. At 40 m depth, all dated otoliths are very young but rather damaged because of locally chemically aggressive sediments, thus showing no correlation between taphonomic grade and postmortem age. Our results show that local conditions and the target species population dynamics must be considered when testing the taphonomic clock hypothesis.

&lt;p&gt;The Messinian Salinity Crisis (MSC) was the greatest paleoenvironmental perturbation the Mediterranean has ever seen. The literature is abundant in hypotheses on the repercussions of the MSC on organisms. However, all these are based on incomplete and still uncertain scenarios about the MSC evolution, as well as on the assumption that such a paleoenvironmental perturbation must have completely reset marine biota. Having prevailed for many decades now, this assumption has leaked from paleontology and geosciences to biological sciences, with numerous studies taking this scenario for granted instead of using it as a starting hypothesis to be tested. Here, we review and revise the marine fossil record across the Mediterranean from the Tortonian until the Zanclean to follow the current rules of nomenclature, correct misidentifications, and control for stratigraphic misplacements. We examine the composition of marine faunas, both taxonomically and considering the function of each group in the marine ecosystem and the transfer of energy through the marine food web. Specifically, we investigate the following functional groups: 1) primary producers, 2) secondary producers, 3) primary consumers, 4) secondary consumers, and 5) top predators. Our study includes sea grasses, phytoplankton, corals, benthic and planktonic foraminifera, bivalves, gastropods, brachiopods, echinoids, bryozoans, fishes, ostracods, and marine mammals. We calculate biodiversity indexes to provide independent evidence quantifying to what degree the marine fauna underwent:&lt;/p&gt;&lt;ol&gt;&lt;li&gt;A drop of overall regional biodiversity of the Mediterranean due to environmental stress during the Messinian.&lt;/li&gt; &lt;li&gt;A taxonomic and functional change between the Tortonian, Messinian, and the Zanclean, that is before and after the MSC, as well as during the precursor events to that actual crisis taking place after the Tortonian/Messinian boundary.&lt;/li&gt; &lt;li&gt;The onset of the present-day west-to-east decreasing gradient in species richness, which has been related to the sea temperature and productivity gradients and the distance from the Gibraltar connection to the Atlantic.&lt;/li&gt; &lt;/ol&gt;

Degradation of coastal environments is an issue that many areas in Europe are facing. In the present work, an ancient coastal lake wetland is investigated, the so-called Lake Lerna in NE Peloponnese, Greece. The area hosted early agricultural populations of modern Greece that started modifying their environment as early as the early–middle Neolithic. Two drill cores in the area of the ancient lake were analysed to establish the sedimentological succession and the depositional environments using sub-fossil assemblages (molluscs and ostracods). Three lithological and faunal units were recovered, the latter being confirmed by the statistical ordination method (non-metric multidimensional scaling). The usage of sub-fossil mollusc species for the first time in the region enriched the dataset and contributed significantly to the delimitation of the faunas. These consist of environments characterised by various levels of humidity (from stagnant waters to freshwater lake) and salinity, with ephemeral intrusions of salt water to the lake, documented by mollusc and ostracod populations. We conclude that the lake and its included fauna and flora were mostly affected by climatic fluctuations rather than human intervention in the area.