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Preserving adaptive capacities of coastal ecosystems, which are currently facing the ongoing climate warming and a multitude of other anthropogenic impacts, requires an understanding of long‐term biotic dynamics in the context of major environmental shifts prior to human disturbances. We quantified responses of nearshore mollusk assemblages to long‐term climate and sea‐level changes using 223 samples (~71,300 specimens) retrieved from latest Quaternary sediment cores of the Adriatic coastal systems. These cores provide a rare chance to study coastal systems that existed during glacial lowstands. The fossil mollusk record indicates that nearshore assemblages of the penultimate interglacial (Late Pleistocene) shifted in their faunal composition during the subsequent ice age, and then reassembled again with the return of interglacial climate in the Holocene. These shifts point to a climate‐driven habitat filtering modulated by dispersal processes. The resilient, rather than persistent or stochastic, response of the mollusk assemblages to long‐term environmental changes over at least 125 thousand years highlights the historically unprecedented nature of the ongoing anthropogenic stressors (e.g., pollution, eutrophication, bottom trawling, and invasive species) that are currently shifting coastal regions into novel system states far outside the range of natural variability archived in the fossil record. [ABSTRACT FROM AUTHOR]

Our study uses data from Holocene core samples and modern death assemblages to understand how human-induced environmental change in the northern Adriatic Sea (Italy) may have affected parasite-host dynamics in the economically important bivalve Chamelea gallina. Thirty-one radiocarbon dates confirm temporal distinctness between the periods before and after the onset of significant human influence and confirm that trematode prevalence has decreased by an order of magnitude over the past ∼2 k.y. The median number of parasite-induced pits per bivalve host and parasite aggregation has also decreased significantly, signaling a substantial decrease in the effective population size of digenean trematodes. Gaussian finite mixture modeling of pit size does not support the hypothesis of parasite extinction. Combined, these results indicate the (potentially ongoing) collapse of parasite-host interactions in C. gallina in concert with human influence on the Adriatic and its transition to an “urban sea.” [ABSTRACT FROM AUTHOR]

Rapid warming and sea-level rise are predicted to be major driving forces in shaping coastal ecosystems and their services in the next century. Though forecasts of the multiple and complex effects of temperature and sea-level rise on ecological interactions suggest negative impacts on parasite diversity, the effect of long term climate change on parasite dynamics is complex and unresolved. Digenean trematodes are complex life cycle parasites that can induce characteristic traces on their bivalve hosts and hold potential to infer parasite host-dynamics through time and space. Previous work has demonstrated a consistent association between sea level rise and increasing prevalence of trematode traces, but a number of fundamental questions remain unanswered about this paleoecological proxy. Here we examine the relationships of host size, shape, and functional morphology with parasite prevalence and abundance, how parasites are distributed across hosts, and how all of these relationships vary through time, using the bivalve Chamelea gallina from a Holocene shallow marine succession in the Po coastal plain. Trematode prevalence increased and decreased in association with the transition from a wave-influenced estuarine system to a wave-dominated deltaic setting. Prevalence and abundance of trematode pits are associated with large host body size, reflecting ontogenetic accumulation of parasites, but temporal trends in median host size do not explain prevalence trends. Ongoing work will test the roles of temperature, salinity, and nutrient availability on trematode parasitism. Parasitized bivalves in one sample were shallower burrowers than their non-parasitized counterparts, suggesting that hosts of trematodes can be more susceptible to their predators, though the effect is ephemeral. Like in living parasite-host systems, trematode-induced malformations are strongly aggregated among hosts, wherein most host individuals harbor very few parasites while a few hosts have many. We interpret trace aggregation to support the assumption that traces are a reliable proxy for trematode parasitism in the fossil record. [ABSTRACT FROM AUTHOR]

Understanding how marine taxa will respond to near-future climate changes is one of the main challenges for management of coastal ecosystem services. Ecological studies that investigate relationships between the environment and shell properties of commercially important marine species are commonly restricted to latitudinal gradients or small-scale laboratory experiments. This paper aimed to explore the variations in shell features and growth of the edible bivalve Chamelea gallina from the Holocene sedimentary succession to present-day thanatocoenosis of the Po Plain-Adriatic Sea system (Italy). Comparing the Holocene sub-fossil record to modern thanatocoenoses allowed obtaining an insight of shell variations dynamics on a millennial temporal scale. Five shoreface-related assemblages rich in C. gallina were considered: two from the Middle Holocene, when regional sea surface temperatures were higher than today, representing a possible analogue for the near-future global warming, one from the Late Holocene and two from the present-day. We investigated shell biometry and skeletal properties in relation to the valve length of C. gallina. Juveniles were found to be more porous than adults in all horizons. This suggested that C. gallina promoted an accelerated shell accretion with a higher porosity and lower density at the expense of mechanically fragile shells. A positive correlation between sea surface temperature and both micro-density and bulk density were found, with modern specimens being less dense, likely due to lower aragonite saturation state at lower temperature, which could ultimately increase the energetic costs of shell formation. Since no variation was observed in shell CaCO3 polymorphism (100% aragonite) or in compositional parameters among the analyzed horizons, the observed dynamics in skeletal parameters are likely not driven by a diagenetic recrystallization of the shell mineral phase. This study contributes to understand the response of C. gallina to climate-driven environmental shifts and offers insights for assessing anthropogenic impacts on this economic relevant species. [ABSTRACT FROM AUTHOR]

An isolated human cranium, dated to the early Eneolithic period, was discovered in 2015 at the top of a vertical shaft in the natural Marcel Loubens gypsum Cave (Bologna area, northern Italy). No other anthropological or archaeological remains were found inside the cave. In other caves of the same area anthropic and funerary use are attested from prehistory to more recent periods. We focused on investigating the circumstances surrounding the death of this individual, since the cranium shows signs of some lesions that appear to be the results of a perimortem manipulation probably carried out to remove soft tissues. Anthropological analyses revealed that the cranium belonged to a young woman. We analysed the taphonomic features and geological context to understand how and why the cranium ended up (accidentally or intentionally) in the cave. The analyses of both the sediments accumulated inside the cranium and the incrustations and pigmentation covering its outer surface suggested that it fell into the cave, drawn by a flow of water and mud, likely from the edges of a doline. The accidental nature of the event is also seemingly confirmed by some post-mortem lesions on the cranium. The comparison with other Eneolithic archaeological sites in northern Italy made it possible to interpret the find as likely being from a funerary or ritual context, in which corpse dismemberment (in particular the displacement of crania) was practiced. [ABSTRACT FROM AUTHOR]

Although general trends in transgressive to highstand sedimentary evolution of river‐mouth coastlines are well‐known, the details of the turnaround from retrogradational (typically estuarine) to aggradational–progradational (typically coastal/deltaic) stacking patterns are not fully resolved. This paper examines the middle to late Holocene eustatic highstand succession of the Po Delta: its stratigraphic architecture records a complex pattern of delta outbuilding and coastal progradation that followed eustatic stabilization, since around 7·7 cal kyr bp. Sedimentological, palaeoecological (benthic foraminifera, ostracods and molluscs) and compositional criteria were used to characterize depositional conditions and sediment‐dispersal pathways within a radiocarbon‐dated chronological framework. A three‐stage progradation history was reconstructed. First, as soon as eustasy stabilized (7·7 to 7·0 cal kyr bp), rapid bay‐head delta progradation (ca 5 m year−1), fed mostly by the Po River, took place in a mixed, freshwater and brackish estuarine environment. Second, a dominantly aggradational parasequence set of beach‐barrier deposits in the lower highstand systems tract (7·0 to 2·0 cal kyr bp) records the development of a shallow, wave‐dominated coastal system fed alongshore, with elongated, modestly crescent beaches (ca 2·5 m year−1). Third, in the last 2000 years, the development of faster accreting and more rapidly prograding (up to ca 15 m year−1) Po delta lobes occurred into 30 m deep waters (upper highstand systems tract). This study documents the close correspondence of sediment character with stratal distribution patterns within the highstand systems tract. Remarkable changes in sediment characteristics, palaeoenvironments and direction of sediment transport occur across a surface named the 'A–P surface'. This surface demarcates a major shift from dominantly aggradational (lower highstand systems tract) to fully progradational (upper highstand systems tract) parasequence stacking. In the Po system, this surface also reflects evolution from a wave‐dominated to river‐dominated deltaic system. Identifying the A–P surface through detailed palaeoecological and compositional data can help guide interpretation of highstand systems tracts in the rock record, especially where facies assemblages and their characteristic geometries are difficult to discern from physical sedimentary structures alone. [ABSTRACT FROM AUTHOR]

The Arda and Stirone marine successions (Italy) represent key sections for the early Pleistocene; they were deposited continuously within a frame of climate change, recording the Calabrian cooling as testified by the occurrence of the "northern guests," such as the bivalve Arctica islandica. In addition, although the first occurrence of A. islandica in the Mediterranean Sea was used as the main criterion to mark the former Pliocene-Pleistocene boundary, the age of this bioevent was never well constrained. Here, we describe the Stirone depositional environment and constrain for the first time the section age using calcareous nannofossil and foraminifera biostratigraphy. We also correlate the Arda and Stirone sections using complementary biostratigraphic and magnetostratigraphic data. Our results indicate that A. islandica first occurred in both the successions slightly below the top of the CNPL7 biozone (dated at 1.71 Ma). Comparisons with other lower Pleistocene Mediterranean marine successions indicate that the stratigraphically lowest level where A. islandica first occurred in the Mediterranean Sea is in the Arda and Stirone sections; these environments satisfied the ecological requirements for the establishment and the proliferation of the species, which only subsequently (late Calabrian) has been retrieved in southern Italy and other areas of the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

Integrating analysis of the benthic palaeoecological record with multivariate ordination techniques represents a powerful synergy able to provide an improved characterization of coastal depositional facies in a sequence stratigraphical perspective. Through quantitative analysis of benthic foraminifer, ostracod and mollusc associations from the postglacial succession of Core M3 ( Arno coastal plain, Tuscany, Italy), and application of detrended correspondence analysis ( DCA) to the mollusc sub-data set, we offer a refined picture of stratigraphical variations in faunal content from a paralic depositional setting, and reconstruct the palaeoenvironmental gradients that account for such variations. Despite distinct ecological behaviours, and taphonomic and sedimentological constraints, a strong ecological control on meio- and macrofaunal biofacies and taxa turnover is documented across the study succession. Amongst all possible mechanisms that may play a role in 'shaping' fossil distribution, the ecological signal driven by salinity represents the most prominent factor controlling the composition of fossil associations in the cored succession. Molluscs can even provide outstanding quantitative estimates of palaeosalinity along the sampled core. When plotted stratigraphically, the three fossil sub-data sets show consistent patterns of vertical evolution that enable prompt identification of the key surfaces for sequence stratigraphical interpretation in otherwise lithologically indistinguishable deposits. The concomitant maximum richness of species with strong marine affinity, paralleled by the highest DCA salinity estimates, allows recognition of the maximum flooding zone, dated to ∼7.7 cal. ka BP, within a homogeneous succession of outer lagoon clays. These clays are sandwiched between early transgressive, swamp to inner lagoon deposits and overlying prograding coastal−alluvial plain facies. [ABSTRACT FROM AUTHOR]

Upper Quaternary sequences of the Po Plain (Italy) were used to assess the informative strength and sequence-stratigraphic overprint of quantitative paleoecological patterns. Three densely sampled cores (89 samples, 98 genera, 23,280 specimens), dominated by extant mollusk species with known environmental distributions, were analyzed with detrended correspondence analysis (DCA). The DCA scores, calibrated using extant genera, provided outstanding estimates of bathymetry (±3 m) and related environmental parameters. Depth-related successions of mollusk associations delineated by using DCA were consistent with independent sequence-stratigraphic interpretations and yielded insights inaccessible via routine techniques (e.g., depth estimates for maximum flooding surfaces). The DCA ordination demonstrates the severity of the sequence-stratigraphic overprint: samples are highly uniform taxonomically during late transgressive systems tracts and highly variable during the following highstand systems tracts. When analyzed across com- parable systems tracts, similar species associations repeat during the last and current interglacial cycles, suggesting that Po Plain mollusk associations have remained remarkably stable over the past 125 k.y. The results are consistent with the bathymetric interpretation of the DC axis 1 postulated previously for the Paleozoic fossil record, demonstrate the sequence-stratigraphic overprint of paleoecological patterns predicted by computer modeling, and illustrate the utility of quantitative paleoecological patterns in augmenting sequence-stratigraphic interpretations. [ABSTRACT FROM AUTHOR]

Combined palaeoecologic and sedimentologic studies reveal remarkable palaeoenvironmental changes in the Pliocene Intra-Apenninic Basin (PIB) of the Bologna Apennines (Northern Italy). At the northern margin of PIB, the stratigraphic succession is approximately 1000 m thick, and displays an overall coarsening-upward trend, including a lower mudstone-dominated succession (Argille Azzurre Formation) of Zanclean age, overlain by a sandstone-rich unit (M. Adone Formation), assigned to the Zanclean-Piacenzian. The vertical succession of biofacies within the Argille Azzurre Fm. indicates an obvious shallowing-upward tendency, from slope/outer-shelf (150–300 m water depths) to inner-shelf (30–50 m) environments. A vertical cyclic pattern of facies, with alternating sandy siltstones and sandstone bodies, characterizes M. Adone Formation. Each elementary cycle, about 30–50 m thick, includes a couple of siltstone-dominated inner-shelf and prodelta deposits, passing upwards into progradational delta front, tabular sand bodies. These high-rank cycles, spanning an interval of time in the order of magnitude of 40 ky, are separated by flooding surfaces, clearly recognizable on the basis of palaeoecologic analysis, and reflect an aggradational stacking pattern of parasequences superposed to the general shallowing-upward trend. [Copyright &y& Elsevier]

We present a detailed paleoecologic analysis of avian assemblages from the Mousterian layers of the Middle Paleolithic Grotta del Cavallo site in southern Italy. Findings improve knowledge of the landscape that was exploited by Neanderthals. During the MIS 7, 6 and 3, the cave was surrounded by extensive grasslands and shrublands, locally interspersed by open woodland and rocky outcrops, whereas the coastal plain (currently underwater) hosted wetlands. Water bird taxa show an increase in population size during the cool-temperate climatic interval attributed to MIS 3, possibly linked to more humid conditions or a shorter distance between the wetland settings and the cave, compared to the previous glacial phase (MIS 6). In addition, coverage-based rarefied richness suggests higher avian diversity during MIS 3, which may reflect greater landscape heterogeneity due to the presence of wetland habitats. The tentative discovery of Branta leucopsis , together with several bird species currently found at higher altitudes, reinforces geochemically-derived palaeoclimate inferences of cooler than the present conditions. These assemblages also include the first fossil occurrence of Larus genei worldwide, the first Italian occurrence of Emberiza calandra , the oldest Italian occurrence of Podiceps nigricollis, and the occurrence of the rarely reported Sylvia cf. communis. Taphonomic analyses indicate that bone modifications are mainly due to physical syn - and post-depositional processes, and that the assemblage mainly accumulated through short-range physical transport and the feeding activities of nocturnal raptors. • Fossil birds from Mousterian layers are analysed in detail for the first time. • The bird taxa showed the presence of open habitats and wetlands. • First fossil occurrence ever of Larus genei and first occurrence in Italy of Emberiza calandra. • The accumulation of bird bones is mainly due to activity of nocturnal raptors and physical processes. • Eco-taphonomic patterns detail the landscape exploited by Neanderthals. [ABSTRACT FROM AUTHOR]

Understanding how marine taxa will respond to climate change is one of the main challengesfor management of coastal ecosystem services and fishing industry. Ecological studies onfactors controlling shell proprieties and morphology of commercially importantmollusk species are necessarily restricted to studies along a latitudinal gradient orsmall-scale laboratory experiments. Few studies, however, have investigated how shellgrowth and microstructure is affected by climate change in the recent fossil record,which offers a quantitative archive of ecological responses to past climate transitions(e.g., Holocene climate optimum). Among economically relevant shellfish, bivalveChamelea gallina seems particularly sensitive to environmental changes, showingmacroscale variation in shell morphology in response to environmental parameters (solarradiation and temperature). This preliminary study investigates skeletal properties andgrowth of C. gallina specimens from the Holocene nearshore deposits of the Pocoastal plain (northern Italy). Here, shell skeletal parameters (micro-density andapparent porosity) and growth parameters (bulk density, linear extension and netcalcification rates) were investigated in relation to shell size and age. We also comparedmorphology and skeletal properties of the fossil assemblages with those of living,harvested populations of C. gallina sampled from the comparable environmentalsetting in the modern North Adriatic Sea. In both the sub-fossil and present-daypopulations, juveniles are more porous than adult specimens, suggesting that C.gallina promote rapid shell accretion at expense of a higher risk of predation inorder to reach earlier the size of sexual maturity (present day ca. 10-16mm) byenabling faster linear extension rates. The inferred biotic response of C. gallina overthe Holocene offers a baseline for understanding the short- to mid-term impact ofanthropogenic warming on this important shellfish species. This in turn, may allowimplementation of more effective management of fishing industry and ecosystem services. [ABSTRACT FROM AUTHOR]

The sedimentary history of the Po River Delta during the Holocene highstand records atransition from wave-dominated, weakly prograding shoreline (∼7.0-2.0 cal ky BP) to rapidlyupbuilding, strongly progradational river-dominated delta lobes of the Roman to modern age(< 2 cal ky BP). We evaluate responses of nearshore molluscan communities to this majorshift in sedimentary dynamics using a series cores drilled throughout the ∼30-m-thickHolocene succession of the present-day Po coastal plain. Changes in diversity andcomposition of fossil assemblages from delta front environments were analyzed within aregional chronostratigraphic framework based on millennial-scale parasequences traceableacross the study area. Rarefied sample-level species richness decreases though timeas the assemblages become increasingly strongly dominated by the opportunisticcorbulid bivalve Lentidium mediterraneum. This pattern is especially pronounced insamples representing lower shoreface and delta front transition facies associations,while mouth bar and upper shoreface/foreshore assemblages remain species poorthroughout the investigated succession. Drastic drops in both local diversity andbetween-sample species turnover combined with increase in average fossil abundance (i.e. thedensity of identifiable fossils per core interval) characterize the samples from theyoungest parasequence. Deposition of this sedimentary unit followed the historical PoRiver avulsion near the Ficarolo village in 1152 AD, which shifted the river towardsits present-day position, and corresponds to the time of intensified anthropogenicmodification of the drainage network. While the reduction in local species richness canbe partly explained by decreasing time averaging in the river-dominated deltaicsuccession, lower turnover and higher fossil abundance in the last parasequence isprimarily driven by the ubiquity of the L. mediterraneum characterized by an explosivepopulation dynamics. The observed changes in the fossil assemblages thus likelyresulted from a combination of taphonomic effects of higher sedimentation rates andecological responses of benthic communities to increased instability of deltaic habitats. [ABSTRACT FROM AUTHOR]

Abstract: The Piacenzian section of Campore (Northern Italy) has been used to determine the paleoecological significance of the muddy upper bathyal mollusc associations of the Mediterranean Pliocene. By employing computer-based strategies (cluster and rarefaction analyses) a Korobkovia oblonga–Jupiteria concava paleocommunity type ( KJ pt) has been defined. The KJ pt comprises a mosaic of local paleocommunities and paleocommunities whose taxonomic and trophic structures are mainly controlled by oxygen content, sediment accumulation rate, turbidity, and trophic resources. Comparison with mollusc coenoclines recognized in Northern Italy (Rio Merli and River Reno sections) suggests that the KJ pt is bracketed between the deepest muddy circalittoral paleocommunities and the deeper bathyal Bathyspinula excisa–Austrotindaria pusio unit (preliminarily described for the Rio Merli section). The KJ pt is very common in Northern Italy outcrops even though reported by previous authors with different names. We interpret this paleocommunity, which does not go beyond the Middle Pliocene, as the last evidence of an upper bathyal environment in the Neogene climatic-oceanographic regime of the Mediterranean. [Copyright &y& Elsevier]

Abstract Shell-rich biodetrital carbonate lithosomes punctuate the Plio-Pleistocene marine shallow-water successions of the Mediterranean basins. These m-thick sedimentary packages often display large-scale clinostratified geometry and show a remarkable rhythmic alternation with mudstone lithosomes. Our palaeoecological analysis defines the depositional settings and hints to the factors involved in the development of these peculiar bio-detrital carbonate units. Six distinct biofacies, have been identified through a two-way cluster analysis based on the macrofossil content, mostly molluscs, and matched with sedimentary facies. These are Aequipecten gr. opercularis and Bittium reticulatum biofacies, Anomia ephippium biofacies, Ditrupa arietina and Tritia semistriata biofacies, Corbula gibba and Saccella commutata biofacies, Timoclea ovata and Corbula gibba biofacies, Timoclea ovata and Anomia ephippium biofacies. Quantitative analyses suggest that these bio-detrital deposits have a multiphase history, and that, along with their bracketing marine mudstones, are not nearshore or shoreface deposits but developed in mid to outer shelf settings. Our results suggest that sea-level change was neither the only nor the main factor controlling the internal stacking pattern of individual biocalcarenites. They provide instead arguments in favour of periodic, high-amplitude climatic/oceanographic oscillations determining significant modifications of the source-to-sink dynamics of the basin and affecting the trophic structure, the supply of terrigenous sediments, as well as the energy and pattern of bottom currents of shelfal areas. Highlights • We present a paleoecological study on Neogene marine macrobenthos of the Appennine. • Our results suggest a new climatic/oceanographic model for biocalcarenite formation. • For this carbonates the eustatic forcing not appear the main genetic parameter. [ABSTRACT FROM AUTHOR]

The Arda and Stirone marine successions (Italy) represent key-sections for the lower Pleistocene, as they deposited continuously within a frame of climate change, recording the Calabrian cooling as testified by the occurrence of the "northern guests" Arctica islandica, Hyalinea balthica and Neogloboquadrina pachyderma left-coiled. Despite its historical importance in the past, when the first occurrence of A. islandica in the Mediterranean Sea was used as the main criterion to mark the former Pliocene-Pleistocene boundary, the age of this bioevent was never well constrained. Here, we describe the Stirone depositional environment and constrain for the first time the section age using calcareous nannofossils and foraminifera biostratigraphy; we correlate the Arda and Stirone sections, complementing biostratigraphic and magnetostratigraphic data. Our results indicate that A. islandica first occurred in both the successions slightly below the top of the CNPL7 biozone (dated at 1.71 Ma). The comparison with other lower Pleistocene Mediterranean marine successions indicates that the stratigraphically lowest level where A. islandica first occurred in the Mediterranean Sea is in the Arda and Stirone sections; these environments satisfied the ecological requirements for the establishment and the proliferation of the species, which only subsequently colonized southern Italy and other areas of the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

Stratigraphic patterns of last occurrences (LOs) of fossil taxa potentially fingerprint mass extinctions and delineate rates and geometries of those events. Although empirical studies of mass extinctions recognize that random sampling causes LOs to occur earlier than the time of extinction (Signor-Lipps effect), sequence stratigraphic controls on the position of LOs are rarely considered. By tracing stratigraphic ranges of extant mollusc species preserved in the Holocene succession of the Po coastal plain (Italy), we demonstrated that, if mass extinction took place today, complex but entirely false extinction patterns would be recorded regionally due to shifts in local community composition and non-random variation in the abundance of skeletal remains, both controlled by relative sea-level changes. Consequently, rather than following an apparent gradual pattern expected from the Signor-Lipps effect, LOs concentrated within intervals of stratigraphic condensation and strong facies shifts mimicking sudden extinction pulses. Methods assuming uniform recovery potential of fossils falsely supported stepwise extinction patterns among studied species and systematically underestimated their stratigraphic ranges. Such effects of stratigraphic architecture, co-produced by ecological, sedimentary and taphonomic processes, can easily confound interpretations of the timing, duration and selectivity of mass extinction events. Our results highlight the necessity of accounting for palaeoenvironmental and sequence stratigraphic context when inferring extinction dynamics from the fossil record., (© 2018 The Authors.)