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Taphonomy and paleoecology of Orciano Pisano “whale- fall” community (W1; IGF 9299V). A: Glossus humanus (IGF 14635E) in life position below neurocranium (dashed line outlines scapula). B: Megaxinus incrassatus (IGF 14634E) in vertical position near left humerus. C: M. incrassatus in horizontal position below a costa (arrow). D: Tip of skull, with Amusium cristatum (long arrows) and M. incrassatus (short arrow). E: Articulated M. incrassatus below heavily damaged large bones. F: Large tooth of Carcharodon carcharias (IGF 9314V). G: Tympanic bulla with deeply cut marks. H: Field view of W1 showing articulated, but damaged caudal vertebrae and lacking dorsal vertebrae. H ′ : Orthogonal sketch of W1 with position of M. incrassatus (circles), G. humanus (stars), and teeth of white shark ( Carcharodon carcharias —open triangles) and blue shark ( Prionace glauca —black triangle). Scale bars are in cm in A, C, and E–G, inches in B, and m in H; D is 90 cm wide.
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The hypothesis that sunken carcasses of Mesozoic marine reptiles and Cenozoic whales acted as evolutionary stepping stones to deep-sea reducing habitats is underlain by the question of whether vent-like, chemosymbiotic specialization first evolved at shelf depths. Fossil skeletons of large whales have long been known from ancient shallow-water stra...
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... of deep-sea ephemeral habitats, such as hydrothermal vents and cold seeps, and biota living off decomposing whale carcasses possess chemosymbiotic adaptations acquired to exploit reduced compounds. This shared ability has suggested that whale falls (Smith et al., 1989; Glover et al., 2005) and, before them, marine reptile carcasses (Marshall, 1994; Kaim et al., 2008) have acted as evolutionary stepping stones to chemosynthetic habitats. Large carcasses from oceanic whales appeared later than chemosymbiotic mollusk specialists (Kiel and Goedert, 2006; Kiel and Little, 2006), but since small carcasses also may host specialized taxa, evolutionary relationships should be reconsidered (Pyenson and Haasl, 2007). Molecular data suggest that specialization found in the deep sea may have fi rst appeared at shelf depths (Distel et al., 2000; Jones et al., 2006; Neulinger et al., 2006). Bone-eating worms related to vent polychaetes found in experimentally deployed shelf whale falls (Glover et al., 2005; Dahlgren et al., 2006) provide some support to this idea. In modern deep-sea carcasses, abundant lipids are exploited by sulfate-reducing bacteria living within bones, and sulfur is also utilized by oxidizing bacteria living chemosymbiotically within bone-dwelling bivalves (Smith and Baco, 2003). Specialized clams and mussels (Vesicomydae, Bathymodiolinae) have a high biomass and are nearly ubiquitous in deep-sea reducing environments, but they are usually lacking on the shelf (Sahling et al., 2003; Tarasov et al., 2005). Natural whale falls are little known in modern shelves, possibly due to resurfacing after decomposition (Smith, 2006), but whale skeletons are relatively common in Neogene shelf sediments, often articulated and complete. A Pliocene whale found associated with a diverse invertebrate assemblage including a chemosymbiotic component offers a starting point for the taphonomic reconsideration of museum specimens. To evaluate the role played by sunken large carcasses on chemosymbiotic specialization within mollusks, bone-associated assemblages were compared with the surrounding macrofauna and with other fossil and modern assemblages from a wide range of normal and reducing marine habitats. The 10-m-long mysticete (W1) was found in shelf sediments at Orciano Pisano, a locality of the paleo-Tuscan archipelago (Italy). Preliminary biostratigraphic data indicate an age between 3.19 and 2.82 Ma old (Appendix DR1 in the GSA Data Repository 1 ). The position of the macrofauna with respect to the whale skeleton was recorded during the excavation (Fig. 1). Half-liter bulk samples were collected to document macrofaunal abundance in sediments directly overlying W1 bones ( n = 6), within a shell bed below the skeleton ( n = 2), and from the background facies ( n = 4). Mollusks in contact with head bones (approximate surface = 2 m 2 ) formed an additional sample. Bulk samples were washed through 0.5-mm-mesh sieves, specimens were counted, and the resulting data were used for multivariate analyses (see Appendix DR2 for a species list). To evaluate the level of generality of the Orciano Pisano fi nding, Italian Pliocene collections were surveyed for partly or wholly articulated skeletons of large whales. Thirteen whales were tested for the taphonomic variables recognized in W1 (Appendix DR3; Fig. 2). We compared fossil and modern data on the abundance and distribution of shelled mollusk families worldwide (Appendixes DR4 and DR5), at depths ranging from coastal to bathyal (0–1600 m), with samples collected at and below W1, for a total of 160 families from 118 samples (Mediterranean: 71 fossil assemblages; Pacifi c: 39 modern and fossil; Atlantic: 8 modern). Periods studied are Eocene ( n = 3), Oligocene (2), Miocene (2), Pliocene (56), Pleistocene (27), and modern (28). Most collections from reducing environments were from depths >200 m (25 in 32 cases). Nonmetric multidimensional scaling (MDS) was performed with the software Primer 5.0 on a similarity matrix measured by the Bray- Curtis dissimilarity coeffi cient (square-root transformed, standardized data; Fig. 3). W1 was found lying on its ventral side in a massive silty, fi ne- grained sandstone, ~20 cm above a shell bed dominated by the gastropod Archimedella spirata . Spatangoid echinoderms, large decapods, and most bivalves (Figs. 1A–1E) occur in life position, all of which are consistent with a low-energy setting below storm-weather wave base. W1 bones maintain their original relative position and are only slightly displaced (Figs. 1H and 1H ′ ), but they are not pristine. Possibly all caudal vertebrae are present, but they lack dorsal processes and are frequently cemented one to the other in the lowermost part. Their cortical bone layer is corroded, exposing a fragile “spongy” bone tissue, increasingly so as the chest region is approached. Thoracic vertebrae are lacking, and cervical bones are cemented. Costae, symmetrical around the vertebral column, preserve a large part of their cortical layer. One tympanic bulla bears bite marks (Fig. 1G). The skull is heavily worn. Macrofossils directly associated with W1 include remains of pelagic (white and blue sharks; Fig. 1F) and benthic predators and scavengers (gastropods, decapods) and many other heterotrophs. Articulated specimens of the chemosymbiotic lucinid Megaxinus incrassatus (for adaptations in lucinids, see Williams et al., 2004) and large specimens of the bivalve Glossus humanus were recovered in life position by the chest and the skull (Figs. 1A–1E). Shark teeth and bite marks suggest scavenging, consistent with the habits of white sharks, which attack whales in pelagic waters, and blue sharks, which dive up to 80–100 m depths (Fergusson, 1996; Kubodera et al., 2007). White sharks were large (Fig. 1F), but the high degree of W1 articulation suggests that they had a limited role in stripping soft tissues away. Successive steps were deduced from taphonomic pathways in some modern deep-water analogs that show analogies with W1 (Allison et al., 1991; Goffredi et al., 2004; Fujiwara et al., 2007). Some modern, heavily downgraded carcasses show badly preserved or missing thoracic vertebrae and corroded skulls while ribs and lumbar and caudal vertebrae are retained (Fujiwara et al., 2007). Costae, tail bones, and jawbones seem to be the fi rst part of the skeleton to be exposed and collapse (Goffredi et al., 2004), whereas soft tissues in the skull remain available for months to years (Fujiwara et al., 2007). Biotic activity is thus expected to be more intense around the chest and the head. High sedimentation rates could explain early burial and low corrosion of the ribs that lay lowest in the pile (Allison et al., 1991; Fujiwara et al., 2007). We infer early exposition of W1 tail bones, ribs, and jaws, and costae undergoing early burial in a soft muddy bottom. Aerobic and anaerobic decomposition followed at the chest and head regions, where bones underwent a prolonged exposure and destruction possibly by bone-eating worms (genus Osedax , hosting heterotroph bacteria; Dubilier et al., 2008) active on the shelf (Glover et al., 2005; Dahlgren et al., 2006). The subsequent sulfophilic stage is inferred from the abundant lucinids, and their uneven distribution along the carcass suggests that higher nutrient content at the chest and the skull fueled a more intense and prolonged chemosynthetic activity (Figs. 1H and 1H ′ ). At the end of the succession, large bones still lying on the bottom offered enhanced fl ow conditions (“reef” stage) to the ...
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After the discovery of whale fall communities in modern oceans, it has been hypothesized that during the Mesozoic the carcasses of marine reptiles created similar habitats supporting long-lived and specialized animal communities. Here, we report a fully documented ichthyosaur fall community, from a Late Jurassic shelf setting, and reconstruct the e...
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... Schäfer (1972) pioneered this type of analysis by describing actualistic taphonomic patterns of drifting and beach-stranded specimens prior to burial. In addition, many studies have focused on deep-marine environments, with particular focus on the ecological impact generated by the sinking of large cetacean carcasses on nutrient-depleted seafloors (i.e., development of whale-fall communities), rather than the processes that led to deposition on the seabed and their taphonomic implications, or the consequences of large carcasses sinking in shallow marine environments (Smith and Baco 2003;Amano et al. 2007;Dominici et al. 2009;Danise et al. 2010;Danise and Dominici 2014;Jenkins et al. 2018). ...
Fieldwork at Península Valdés (Chubut, Argentina) in the Puerto Madryn Formation (Late Miocene) resulted in the discovery of a well-preserved, almost fully articulated, baleen whale (Cetacea, Mysticeti). This specimen, one of the most complete balaenid skeletons known from the Neogene of Argentina and worldwide, was the focus of a taphonomic analysis employing a multidisciplinary approach, integrating taxonomic, sedimentological, stratigraphic, and ichnological analyses, with the aim of reconstructing the taphonomic processes and the paleoenvironmental conditions that controlled preservation of the specimen. The skeleton belongs to the family Balaenidae (right whales). It displays a high degree of articulation, moderate pre-burial fragmentation, and relatively high completeness. Our results suggest that after death, the balaenid suffered a brief biostratinomic phase that can be summarized in four stages: (1) death at sea, with initial decomposition and positive buoyancy of the carcass; (2) internal accumulation of putrefaction gases, re-orientation, then gas loss; (3) sinking and deposition in a ventral-up position on the sea floor of the inner shelf; and (4) lateral re-orientation of the postcranial region due to physical and biological processes. The high degree of articulation and association of the skeletal elements, and the presence of both mandibles, indicate no lateral transport on the seabed and excludes refloating of the carcass at any stage. Finally, the data indicate a low-energy shelf environment with normal marine benthic oxygenation and salinity conditions, characterized by a soft bottom and a moderate sedimentation rate. The last, combined with high bioturbation, plus scour-induced self-burial, resulted in rapid burial of the carcass.
... The specimen was prepared at the Musei Civici di Reggio Emilia (hereinafter MCRE) and received the accessory number MCRE 232834. This skeleton was exposed in a special exhibition; it was presented in three brief reports (Chicchi & Scacchetti, 2003;Chicchi & Bisconti, 2014;Bisconti et al., 2021a) and mentioned in a number of papers focused on whale falls as the Castellarano mysticete (Dominici et al., 2009(Dominici et al., , 2019, and in the revision of the chronostratigraphy of Italian fossil cetaceans Freschi & Cau, 2020). Bisconti et al. (2021b) reconstructed both the total length and the body mass of MCRE 232834 in a new, comprehensive analysis of the body size evolution of Balaenidae and inferred the phylogenetic relationships of this specimen based on a set of morphological data (Fig. 2). ...
... close to the right dentary (g); Cosmopolitodus hastalis close to the pelvis (h); Hexanchus griseus between second and third caudal vertebrae (i); Cosmopolitodus hastalis (j); Hexanchus griseus (k) found in the level of the whale but not in close association to the skeleton. Scale bars equal 1 cm. of the reef stage on MCRE 232834 was previously documented by Dominici et al. (2009; in that paper, MCRE 232834 was called W9 -Castellarano specimen). ...
A partial skeleton of a Pliocene balaenid whale (Mammalia, Cetacea, Mysticeti) is described and compared to a large set of extant and fossil Balaenidae. The specimen (MCRE 232834) includes a jugal, both mandibular rami and part of the postcranial skeleton including several vertebrae, complete ribs, hyoid, pelvis, a single scapula and a single partial forelimb. The specimen was found at a site in the vicinity of the San Valentino Castle, about 16 km S from Reggio Emilia, close to the town of Castellarano, Emilia Romagna (northern Italy). Molluscs and foraminifers indicate a late Zanclean age for MCRE 232834, constrained between 3.8 and 3.6 Ma. A taphonomic analysis revealed that after death the individual sunk on the sea floor upside down and underwent a series of biostratinomic processes eventually leading to the collapse of the ribcage and to the disarticulation of the posterior thoracic, lumbar and caudal vertebrae, together with the loss of several skeletal elements including the skull. Shark teeth and encrusting molluscs demonstrate that the specimen was exploited by different organisms during its decay. The study of the skeleton revealed that MCRE 232834 shows an abruptly converging anterior ends of the mandibular rami, well-developed olecranon process in the ulna, peculiar morphology of the cervical vertebrae and enlarged attachment sites for axial muscles in the ribs. Based on the morphology of the cervical vertebrae, mandible and scapula, MCRE 232834 can be assigned to a new genus and species of the family Balaenidae, i.e., Charadrobalaena valentinae n. gen., n. sp., which is part of a primitive clade of balaenids that is the sister group of the crown balaenid whales. A functional analysis of the vertebral column revealed that it was able of comparatively faster and more agile swimming with respect to the extant balaenid species.
... All specimens are depicted in lingual view. . Data after the many works by Vicens and Gracia [25], Bianucci et al. [11], Bisconti [26], Dominici et al. [27], Adnet et al. [28], Pawellek et al. [29], Danise and Dominici [30], Freschi [31], Bendella et al. [32], Bernárdez and Rábano [24], Zazzera et al. [33] and Collareta et al. [22]. Note that records that originate from outside the Mediterranean (palaeo)geographic domain (e.g., from the Guadalquivir Basin of southern Spain; [34]) are not shown in the figure. ...
... The position of the Pliocene-Pleistocene boundary follows Gibbard et al. [35]. . Data after the many works by Vicens and Gracia [25], Bianucci et al. [11], Bisconti [26], Dominici et al. [27], Adnet et al. [28], Pawellek et al. [29], Danise and Dominici [30], Freschi [31], Bendella et al. [32], Bernárdez and Rábano [24], Zazzera et al. [33] and Collareta et al. [22]. Note that records that originate from outside the Mediterranean (palaeo)geographic domain (e.g., from the Guadalquivir Basin of southern Spain; [34]) are not shown in the figure. ...
... As for the largest individual of C. carcharias to have ever been reliably measured, i.e., the 594 cm long female from Ledge Point, it displays a maximum TEH value of 51 mm [58]. Of the 132 modern white shark specimens that comprise the database behind Adnet et al.'s ( [27]: Figure 3) analysis, which gathers measurements from several earlier works, none seem to reach TEH values greater than De Stefano's [60] largest fossil specimen. To summarise, the various Mediterranean Pliocene teeth that display TEH > 52 mm appear to have no modern counterparts. ...
The white shark, Carcharodon carcharias, is the main top predator of the present-day Mediter-ranean Sea. The deep past of C. carcharias in the Mediterranean is witnessed by a rather conspicuous, mostly Pliocene fossil record. Here, we provide a synthesis of the palaeobiology and palaeoecology of the Mediterranean white sharks. Phenetically modern white shark teeth first appeared around the Miocene-Pliocene transition in the Pacific, and soon after in the Mediterranean. Molecular phyloge-netic analyses support an origin of the Mediterranean white shark population from the dispersal of Australian/Pacific palaeopopulations, which may have occurred through the Central American Sea-way. Tooth dimensions suggest that the Mediterranean white sharks could have grown up to about 7 m total length during the Pliocene. A richer-than-today marine mammal fauna was likely pivotal in supporting the Mediterranean white sharks through the Pliocene and most of the Quaternary. White sharks have seemingly become more common as other macropredators declined and disappeared, notwithstanding the concurrent demise of many potential prey items in the context of the latest Pliocene and Quaternary climatic and environmental perturbations of the Mediterranean region. The overall generalist trophic habits of C. carcharias were likely crucial for securing ecological success in the highly variable Mediterranean scenario by allowing the transition to a mostly piscivorous diet as the regional marine mammal fauna shrank.
... Tale ritrovamento conferma che al tempo della Crisi Messiniana il Mediterraneo era, sia pur limitatamente e a fasi alterne, nelle condizioni di ospitare fauna marina ed ecosistemi più o meno strutturati che includevano predatori apicali (Carnevale et al. 2008) e anche grandi vertebrati marini (Mas et al. 2018). E' noto che dopo la Crisi di Salinità, nel corso del Pliocene e del Pleistocene, ampie aree della Toscana e dell'Italia centrale divennero habitat per una ricca e variegata fauna marina che comprendeva cetacei piccoli e grandi oltre a complesse biocenosi saprofaghe (whale-fall communities) legate alla decomposizione delle loro carcasse (Dominici et al. 2009, Baldanza et al. 2018. Non è irragionevole supporre che habitat similari, sia pure meno estesi, stabili e con minore biodiversità, caratterizzassero le regioni tirreniche anche nel corso della Crisi di Salinità, considerata anche la presenza localizzata (es. ...
Nel Miocene Superiore il Bacino Mediterraneo sperimentò una serie di mutamenti nella configurazione geologica e idrologica culminati tra i 5,97 e i 5,33 Ma con la Crisi di Salinità del Messiniano (o Evento Messiniano), quando movimenti tettonici tra Nord Africa e Penisola Iberica limitarono fortemente gli afflussi marini dall'Atlantico al Mediterraneo con drastica riduzione in quest'ultimo degli apporti idrici, concentrazione evaporativa delle acque e accumulo diffuso di evaporiti, in particolare gesso (CaSO4•2H2O) e salgemma (NaCl). Due contesti deposizionali distinti per batimetria caratterizzarono l'area mediterranea: bacini marginali poco profondi (<200 m), nei quali si accumularono gessi selenitici anche macrocristallini (>1 m) alternati a peliti euxiniche e/o calcari, e bacini profondi (>200 m) in cui ad una iniziale (~5,97-5,6 Ma) sedimentazione in prevalenza pelitica a carattere euxinico seguì (<5,6 Ma) accumulo di evaporiti clastiche ed evaporiti cumulitiche (es. salgemma, gesso balatino). Condizioni evaporitiche meno intense si registravano in alcune aree del Mediterraneo Occidentale a maggiore influenza marina atlantica (es. Penisola Iberica, Baleari, Algeria), come attestano locali alternanze cicliche di silicoclasti in facies da alluvionale a fluviodeltizia e carbonati in facies lagunare o di piattaforma, incluse stromatoliti e altri calcari microbialitici, depositi che insieme costituiscono il Complesso Carbonatico Terminale (Terminal Carbonate Complex, abbreviato CCT o TCC). L'area tirrenica fu coinvolta anche essa negli squilibri idrologici e ambientali della Crisi di Salinità del Messiniano ma in misura apparentemente minore rispetto ad altre aree dove le facies evaporitiche mostrano potenza ed estensione areale considerevoli (es. Sicilia, Vena del Gesso, Bacino Terziario Piemontese). In Toscana soltanto alcune sezioni (es. Migliarino, Castellina Marittima) mostrano cicli gesso-peliti assimilabili per potenza e associazioni di facies a quelli della Vena del Gesso, localmente (es. Castellina Marittima) interessati da deidratazione, conversione in anidrite (CaSO 4) e successiva reidratazione a formare gesso sericolitico. Sotto il profilo geologico e paleontologico gli affioramenti messiniani dell'area tirrenica mostrano tuttavia caratteristiche peculiari e distintive che potrebbero assimilarli alle coeve e omologhe facies del Mediterraneo Occidentale rivelando utili, finanche inattese informazioni sul contesto paleoambientale dell'Italia tirrenica al tempo della Crisi di Salinità del Messiniano.
... A. fragilis is a representative of the Lucinidae, one of the bivalve families known to host chemosynthetic bacteria Glover, 2005, 2006;Duperron et al., 2013). Chemosymbiotic bivalves are components of recent (Smith and Baco, 2003) and fossil (Amano and Little, 2005;Dominici et al., 2009;Danise et al., 2010) whale fall communities during the sulphophilic stage (Smith et al., 2002(Smith et al., , 2014. Finally, the presence of nonchemosymbiotic molluscs close to the skeleton, such as Venus nux, suggests its colonization during the following reef stage (Smith et al., 2002(Smith et al., , 2014. ...
... Indeed, the scarcity of Pleistocene evidence could be due to the above outlined fragmentary Pleistocene record of cetaceans rather than to a change in prey preferences of white shark during this epoch. Such a scenario is also supported for the Mediterranean basin: evidences of trophic interaction (predation and/or scavenging) between cetaceans and white sharks are well documented today (Bianucci et al., 2000;Boldrocchi et al., 2017), whereas white shark teeth associated with skeletal remains or marks compatible with C. carcharias bites have been previously reported in four and six skeletons of odontocetes and mysticetes, respectively, all from different Italian Pliocene localities (Bianucci et al., 2000;Dominici et al., 2009;Freschi, 2017) but never from Quaternary deposits, with the only exception of the Bari whale. ...
... Interestingly, this phase is generally observed in carcasses that fall in deep waters, not in shallow water as the Bari whale. Indeed, the examined record represents the second documented case, in addition to a chemosynthetic mollusc associated to a whale in a shallow water deposit of the Pliocene of Tuscany (Italy) (Dominici et al., 2009). The fourth reef stage is testified by Venus nux and other molluscs found near the bones. ...
An almost complete and partially articulated skeleton of an Early Pleistocene baleen whale is here described. The fossil, measuring 11 m in length, was discovered in the Calcarenite di Gravina Formation at Lama Lamasinata site (Bari, southern Italy) in 1968. The bifurcated first rib combined with other characters supports the identification of the fossil whale as a possible undescribed species of Balaenoptera (Mysticeti, Balaenopteridae), close to or nested in the B. borealis–B. edeni–B. ricei clade. However, the limited number of preserved diagnostic characters suggests a prudent assignment of the Bari whale to Balaenoptera sp. The associated molluscs suggest a mid-shelf setting deposition near to the boundary between infralittoral and circalittoral environments, probably 40-60 m deep. An associated Carcharodon carcharias tooth (the first case of a possible trophic interaction between white shark and cetaceans in the Pleistocene) and shark bite marks on a rib support the hypothesis that an early scavenger action prevented the rising of the whale carcass because of the removal of abdominal tissues and the consequent reduction of the decomposition gas accumulation. The occurrence of chemosymbiotic bivalves near the skeleton could testify the development of the sulphophilic stage during decay. Overall, the Bari whale skeleton and its associated fossil fauna represent the first well-documented case of Pleistocene whale fall community. The Bari specimen sheds new light on the diversity and disparity of the mysticete fauna in the Mediterranean Pleistocene also related to the geodynamic, palaeoclimatic and palaeoceanographic conditions that favoured upwelling events and nutrients supply into the southern Adriatic basin.
... Stage 2 is detected based on the presence of holes and galleries of the kinds described by Muniz et al. (2010) and Higgs et al. (2012); these structures may be coalescent and may destroy the edges of the vertebral processes (see Higgs et al., 2012 for relevant illustrations). Stage 3 can be detected based on peculiar bioerosion on the bone surface due to the action of the microbial mat as described by Allison et al. (1991) and by presence of chemosymbiotic molluscs as discussed by Dominici et al. (2009). Stage 4 is detected based on the presence of encrusting organisms on the bones like barnacles and molluscs. ...
... They found that the high disarticulation and dispersion pattern, together with the diffuse bioturbation of the bones, was consistent with the late burial of the skeleton as inferred from sedimentological and palaeoecological analyses. Dominici et al. (2009) described the field taphonomy at a Pliocene whale fall from Tuscany. The specimen appears relatively complete but specific portions are absent; these include part of the skull, the thoracic vertebrae, and most of the forelimbs. ...
... The Authors inferred prolonged exposure of different parts of the skeleton to biotic degradation (skull, dentaries, thoracic vertebrae) and assumed early burial for other parts (caudal vertebrae, ribs), thereby evidencing a complex biostratinomic path for this whale. Dominici et al. (2009) hypothesised high sedimentation rate for the early burial and lack of corrosion of the wellpreserved portions, and late burial of the poorly preserved parts of the skeleton. Differential preservation conditions were documented in another balaenopterid from the early Pliocene of Tuscany (Scotton et al., 2018) suggesting that numerous, small-scale sedimentary supplies may have been responsible for the complete burial of selected carcasses over a prolonged temporal interval. ...
The Tertiary Piedmont Basin (TPB) is located in northwestern Italy and represents the western portion of a long and wide basin occupying the area that is now known as the Po Plain. Largely continuous sedimentation occurred in this basin from the early Miocene to the Pleistocene; two Pliocene marine formations are well known from this basin: Argille Azzurre and Sabbie d'Asti formations. Both these formations are rich in marine fossils including numerous cetacean specimens. We analysed the Pliocene mysticete partition of the TPB cetacean record including 55 baleen whale specimens from two museum collections to interpret the taphonomic factors influencing the preservation potential of the basin. Careful observations of bones were performed to find evidence of causes of death, floating and transport, interactions with sharks, timings of burial and whale fall activity. Analysis of preservation of specific bones (vertebrae, mandible, forelimb) was performed in order to discriminate between different mechanisms of transport in the water column or on the seafloor. We found that biostratinomic agents were active all along the basin in both the formations; these included scavenging, bottom currents and the activities of bacteria and whale fall communities. Intense shark-cetacean interactions are recorded by shark bite traces on mysticete bones. Patterns of preservation of vertebrae and loss of paired appendages are used as evidence of floating and transport on the seafloor. A mix of early and late burials is inferred on a specimen basis allowing for the characterisation of the complete biostratinomic history of each mysticete specimen. We suggest that many factors are responsible for good preservation in the TPB mysticete record; these include relative timing of burial and intensity of biostratinomic processes active prior to burial.
... Danise et al., 2012;Gioncada et al., 2018). This observation agrees with the results of Dominici et al. (2009), who found that in a large sample of Pliocene whale falls from the Mediterranean shelf and coastal settings, there was no evidence of a well-structured and specialized trophic chain, such as those that can be observed flourishing thanks to the carcasses of modern baleen-bearing whales. ...
... Apart from exceptional situations, such as those found in Miocene and Pliocene formations in Peru (e.g. Brand et al., 2004;Esperante et al., 2009;Gariboldi et al., 2015;Gioncada et al., 2018) and Argentina (Cuitiño et al., 2019), single mysticete individuals discovered through palaeontological investigations deserve special analyses carried out on an individual basis because of their unpredictable palaeoecological settings (e.g. Dominici et al., 2009;Belaústegui et al., 2011). Works carried out on Italian fossil mysticetes have revealed a complex set of taphonomic situations and stratigraphical/sedimentological controlling factors that have yet to be understood fully at a basin level (e.g. ...
Marzanoptera tersillae gen. & sp. nov., a new balaenopterid from the Pliocene of the Piedmont in north-west Italy, is described based on a partial skeleton and compared with other living and fossil baleen whales. Marzanoptera tersillae shares characters, such as the shape of the supraoccipital, glenoid fossa of the squamosal and zygomatic process of the squamosal, with ‘Balaenoptera’ bertae. We used a computed tomography scan to view parts of the skull that were otherwise impossible to observe, such as the periotic. A phylogenetic analysis based on 355 character states scored from 87 taxa revealed a well-resolved hypothesis of relationships for Balaenopteridae and a general phylogenetic hypothesis for chaeomysticetes. The monophyly of all superfamily- and family-rank clades and of crown balaenopterid species was confirmed. In addition, a monophyletic group including most basal thalassotherian taxa was recovered. The mollusc fauna associated with the specimen was autochtonous and constituted a residual fossil assemblage indicative of an environmental context located below the base of the storm wave, characterized by a low-energy hydrodynamic regimen. Many shark teeth have been found in close association or embedded within the bones, suggesting a possible scavenging action by two shark species on the whale carcass.
... In addition to observing in the lateral view slight subsidence in the supraoccipital region and in the ventral view, a little compaction in the tympanic bulla, this deformation is associated with the process of fossilization and transport. Dominici et al. (2009) point out that in shallow environments, unlike what happens in deep areas where the biological processes that cause the destruction of bones seem to be more predictable, whale skeletons are subjected to an interval of taphonomic processes that are possibly much broader and more variable. ...
Balaenopteroidae is a diverse superfamily within the mysticetes that consists of numerous recent fossil species. The publication of new taxa has increased, which improves the knowledge about this group. In this work, we name and describe Kennedycetus pericorum from the Late Miocene deposits of the Trinidad Formation in Baja California Sur, Mexico. Our phylogenetic results indicate that this is a step taxon, far from the balaenopterid crown group, that is closely related to Norrisanima miocaena from the Monterey Formation, California. The associated fauna of K. pericorum includes the internal molds of different mollusks attributable to Glycymeridae, Semelidae, and Lucinidae, which indicate a coastal environment of warm waters.
... Associations of invertebrates with vertebrate remains may occur in both shallow [77][78][79][80][81] and deep [82] marine settings, and have been studied both in the present [83][84][85][86][87] and in the fossil record [88,89]. Invertebrates are particularly common on and around whale carcasses, where they may account for distinct 'whale-fall' communities [90,91]. ...
The Miocene Pisco Formation, broadly exposed in the Ica Desert of southern Peru, is among the most outstanding Cenozoic marine Fossil-Lagerstätten worldwide. It is renowned for its exceptional preservation and abundance of vertebrate fossils, including a
rich assemblage of whales and dolphins (Cetacea). Here, we integrate taphonomic data on 890 marine vertebrate fossils, gathered through 16 different localities. Our observations range from the taxonomic distribution, articulation, completeness, disposition and orientation of skeletons, to the presence of bite marks, associations with shark teeth and macroinvertebrates, bone and soft tissue preservation, and the formation of attendant carbonate concretions and sedimentary structures. We propose that the exceptional preservation characterising many Pisco vertebrates, as well as their exceptionally high abundance, cannot be ascribed to a single cause like high sedimentation rates (as proposed in the past), but rather to the interplay of several favourable factors including: (i) low levels of dissolved oxygen at the seafloor (with the intervention of seasonal anoxic events); (ii) the early onset of mineralisation processes like apatite dissolution/recrystallisation and carbonate mineral precipitation; (iii) rapid burial of carcasses in a soupy substrate and/or a novel mechanism involving scour induced self-burial; and (iv) original biological richness. Collectively, our observations provide a comprehensive overview of the taphonomic processes that shaped one of South America’s most important fossil deposits, and suggest a model for the formation of other marine vertebrate Fossil-Lagerstätten.
... Associations of invertebrates with vertebrate remains may occur in both shallow [77][78][79][80][81] and deep [82] marine settings, and have been studied both in the present [83][84][85][86][87] and in the fossil record [88,89]. Invertebrates are particularly common on and around whale carcasses, where they may account for distinct 'whale-fall' communities [90,91]. ...
Among the most outstanding Cenozoic marine Fossil-Lagerstätten worldwide, the Peruvian Pisco Formation is renowned for its exceptional preservation and abundance of fossil vertebrates, especially cetaceans. We present an updated overview and interpretation of taphonomic data gathered during fifteen field campaigns (2006-2019) on 890 fossil marine vertebrates from the Miocene strata of the Pisco Formation exposed in the Ica Desert. In order to assess the factors that led to the formation of such an exceptional Konzentrat- and Konservat-Lagerstätte, we made observations that range from the taxonomic distribution, articulation, completeness, disposition and orientation of skeletons, to the presence of bite marks, associations with shark teeth and macro-invertebrates, bone and soft tissue (i.e., baleen) preservation, and the formation of attendant carbonate concretions and sedimentary structures. We propose that the exceptional preservation and abundance of the Pisco Formation specimens cannot be ascribed to a single cause, but rather to the interplay of favorable palaeoenvironmental factors and suitable timing of mineralizing processes, such as: i) low concentration of dissolved oxygen at the seafloor; ii) the early onset of mineralization processes; iii) rapid burial of the carcasses; and iv) original biological richness in the southeastern Pacific. Our observations provide a comprehensive overview of the taphonomic characteristics of one of the most significant fossiliferous deposits of South America and lead to the elaboration of a complex scenario for the preservation of its marine vertebrates that might serve as a reference for explaining the formation of other marine vertebrate Fossil-Lagerstätten worldwide.
