Baleen whales are among the largest animals ever and engineer marine ecosystems by transporting nutrients both vertically through the water column and across vast oceanic distances. Hidden underwater, their feeding habits often remain unseen and hence must be studied indirectly based on stomach contents and stable isotopes. Here, we explore the potential of bone‐bound calcium isotopes as a chemical proxy for extant baleen whal...

Evidence of trophic interactions between sharks and cetaceans is rather widespread in the fossil record, consisting as it does of tooth marks on bones and rarer teeth or tooth fragments embedded in (or associated with) skeletal remains. Here, we reappraise a partial mysticete (baleen whale) forelimb that was collected more than a century ago from Pliocene deposits exposed at the celebrated fossil locality of Orciano Pisano (Tu...

A fossil mysticete was discovered along the southwestern coast of Spain, occurring in a block detached from the Neogene deposits exposed along a coastal cliff at the locality of Conil de la Frontera (Cádiz, Spain). These deposits range from Pliocene to Pleistocene in age and include shallow-marine, mixed carbonate–siliciclastic sediments, with the whale being found in occurrence of a stratigraphic unconformity marked by Thalas...

The extinct “false mako” shark, Parotodus benedenii (Lamniformes: Otodontidae), is essentially known from large, robust teeth that are widespread but overall rare in Oligocene to Pliocene deposits worldwide. More than 150 years after its description, this species still represents a palaeontological conundrum, as very little is known about its body aspect and palaeoecology. Here, we describe new specimens of P. benedenii from t...

Quarries are areas of pivotal importance for investigation, popularization, and educational purposes in the field of geosciences. Here, we focus on three quarries of Tuscany (La Serra, Arcille, and Certaldo) that have been home to significant finds of marine vertebrate fossils. The three selected localities are representative of the many active (La Serra), inactive (Arcille), and abandoned (Certaldo) Tuscan quarries where vert...

In contrast to other kinds of biological interactions, symbiosis is a scarcely investigated aspect of the fossil record. This is largely due to taphonomic biases that often frustrate any attempt to make a strong case that two organisms shared an intimate association in life. Among extant marine vertebrates, the sea turtles (Cheloniidae and Dermochelyidae) bear a broad and diverse spectrum of epibiotic symbionts, including spec...

In order to investigate the serendipitous find of a gastropod encrusted by the symbiont-bearing colonial coral Oculina patagonica, we examined several specimens of cnidarian-encrusted gastropods, ranging in age from the Pliocene to the Recent, and characterized in detail their sclerobiont cover. The results of our analysis suggest that gastropod shells can be encrusted by symbiont-bearing colonial corals at various times: (1)...

In spite of the widespread occurrence of epibiotic turtle barnacles (Coronuloidea: Chelonibiidae and Platylepadidae) on extant marine turtles (Chelonioidea: Cheloniidae and Dermochelyidae), and although the association between these cirripedes and their chelonian hosts has existed for more than 30 million years, only a few studies have investigated the deep past of this iconic symbiotic relationship on palaeontological grounds...

Nowadays, the requiem sharks comprise one of the most diverse and widespread families of selachians, i.e., Carcharhinidae. Among the carcharhinids, the genus Carcharhinus has the largest number of living species, namely, at least 35. Known from fossils as old as the Cretaceous, the requiem sharks did not significantly radiate before the Eocene (when Carcharhinus also appeared), and their diversification mainly occurred in Neog...

The northward-flowing Humboldt Current hosts perpetually high levels of productivity along the western coast of South America. Here, we aim to elucidate the deep-time history of this globally important ecosystem based on a detailed palaeoecological analysis of the exceptionally preserved middle–upper Miocene vertebrate assemblages of the Pisco Formation of the East Pisco Basin, southern Peru. We summarise observations on hundr...

Here we report on four highly peculiar skate teeth from Arcille and Certaldo, two Pliocene localities of Tuscany (central Italy). While being attributable to Rajiformes and somewhat reminiscent of Dipturus and Rostroraja , these specimens display an unusual multicuspid tooth design that does not match any extinct or extant skate taxon known to date. The studied teeth are thus referred to a new genus and species of Rajiformes,...