The world’s oldest fossil seal record

Cajus Diedrich
DOI: 10.4236/ns.2011.311117                

Abstract

A femur fragment with an Early Lutetian (early Middle Eocene) age is the world’s oldest fossil record from a seal, and, is described as Praephoca bendullensis nov. gen. nov. spec. This find pushes back the earliest evolution of seals into the Paleocene epoch. The femur has plesiomorphic terrestrial mammal characteristics but has a morphology that is already closer to that of Miocene and present day seals. The Eocene seal femur was found at Fürstenau-Dalum in north-west Germany, in a conglomerate rich in shark teeth that was deposited in a coastal delta environment to the north-west of the central European Rhenish Massif mainland, in the southern pre-North Sea Basin. This discovery has led to a revision of the theory that phocids originated along the coastline of the North American continent. Instead they can now be interpreted to have originated in the tropical Eocene climate of central Europe. Although the fossil records of pinnipeds in Europe during the Eocene, Oligocene and Miocene are extremely sparse, they appear to have inhabited the pre- North Sea basin, within the influence of temperate and arctic upwellings. The distribution of abundant teeth from white and megatooth sharks of two different lineages appears to correlate with that of the seals, which the sharks most probably hunted; providing supporting evidence that the phocids were already adapted as shallow marine coastal inhabitants by this time.

Keywords

Oldest Seal Remains; Praephoca bendullensis Nov. Gen. Nov. Spec.; Giant Shark Predation; Middle Eocene; Shallow Marine Coastal Deltaic Influenced Habitats; Pre-Northsea Basin of Central Europe

Conflicts of Interest

The authors declare no conflicts of interest.

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