Modern marine waters are inhabited by more than 500 shark species. Among them, the great white shark (Carcharodon carcharias) occupies the topmost position of most marine food pyramid, representing the apex predator of the present-day global ocean. Even if Carcharodon carcharias is well-known as a formidable active predator of marine mammals (pinnipeds and odontocetes), it also constitutes an example of scavenger. In fact, several anecdotal and scientific documentation exists for white sharks feeding on floating whale carrions, which are rich in blubber, and as such, highly energetic food. Given the latest Miocene origin of C. carcharias, the Plio–Pleistocene marine deposits preserve occasional evidence for the feeding activity of white sharks in the form of bite marks on bones and teeth embedded into (or closely associated with) marine mammal bones. Here, we report on a new example of white shark-cetacean trophic interaction evidence from Pliocene shelf sediments of the Argille Azzurre Formation exposed at Monterotondo Marittimo (Tuscany, Italy). The fossil specimen described herein consists of a well-preserved cetacean scapula whose lateral surface is densely incised by serrated shark bite marks up to several centimeters long. Based on osteoanatomical considerations, the scapula can be referred to as a likely diminutive extinct member of Balaenidae (right and bowhead whales, which are no longer part of the poorly diverse Mediterranean fauna), about 8 m long. In addition, during the recovery operations, a shark tooth fragment was found embedded into the scapular. Considering the fragmentary nature of the studied specimen, whether the observed bite marks represent scavenging or active predation could not be assessed. What is remarkable here is the kind of trophic interaction that it witnesses, which includes a member of a baleen whale morphotype that is no longer present in the modern Mediterranean Sea, not even in the rest of the global ocean.
IT’S DINNER TIME: GREAT WHITE SHARK (CARCHARODON CARCHARIAS) BITE MARKS ON RIGHT WHALE REMAINS FROM THE ITALIAN PLIOCENE
Marco Merella
Primo
;Alberto CollaretaSecondo
;Alice PieriPenultimo
;Giovanni BianucciUltimo
2023-01-01
Abstract
Modern marine waters are inhabited by more than 500 shark species. Among them, the great white shark (Carcharodon carcharias) occupies the topmost position of most marine food pyramid, representing the apex predator of the present-day global ocean. Even if Carcharodon carcharias is well-known as a formidable active predator of marine mammals (pinnipeds and odontocetes), it also constitutes an example of scavenger. In fact, several anecdotal and scientific documentation exists for white sharks feeding on floating whale carrions, which are rich in blubber, and as such, highly energetic food. Given the latest Miocene origin of C. carcharias, the Plio–Pleistocene marine deposits preserve occasional evidence for the feeding activity of white sharks in the form of bite marks on bones and teeth embedded into (or closely associated with) marine mammal bones. Here, we report on a new example of white shark-cetacean trophic interaction evidence from Pliocene shelf sediments of the Argille Azzurre Formation exposed at Monterotondo Marittimo (Tuscany, Italy). The fossil specimen described herein consists of a well-preserved cetacean scapula whose lateral surface is densely incised by serrated shark bite marks up to several centimeters long. Based on osteoanatomical considerations, the scapula can be referred to as a likely diminutive extinct member of Balaenidae (right and bowhead whales, which are no longer part of the poorly diverse Mediterranean fauna), about 8 m long. In addition, during the recovery operations, a shark tooth fragment was found embedded into the scapular. Considering the fragmentary nature of the studied specimen, whether the observed bite marks represent scavenging or active predation could not be assessed. What is remarkable here is the kind of trophic interaction that it witnesses, which includes a member of a baleen whale morphotype that is no longer present in the modern Mediterranean Sea, not even in the rest of the global ocean.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
