The world’s oldest fossil seal record

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 preNorth 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.

Evolution of white and megatooth sharks, and evidence for early predation on seals, sirenians, and whales

“…Whereas the excavation allows clear fossil amounts, the private collection allows presenting the biodiversity (rare fossils) and analyses of selected species with better amounts. This collection contains approximately 250,000 shark teeth, about 12,000 fish otoliths [15], many different kinds of macro invertebrate, and vertebrate fossils that include a few terrestrial mammal teeth and marine mammal bone fragments [10,12,13]. From this collection, together with the newly excavated material, about 2000 serrated teeth from Carcharodon and Otodus were separated for this study.…”

“…Some of the individual teeth collected in Europe from the Late Oligocene to Early Miocene "O. angustidens" must be ascribed to the Rupelian (Early Oligocene) species O. sokolovi (Figures 1 and 2), as seen in the material compared herein from the proto North Sea Basin (German localities at Eckelsheim and Espenhain). O. angustidens (Agassiz, 1843), which is known from isolated teeth from the northwest German Doberg site (Late Oligocene, proto North Sea Basin) [12,13]. Proof of this lateral cusplets reduction is found in the complete tooth set and partial O. angustidens skeleton found in Ne Zealand, which either no longer has any clearly developed cusplets on the anterior teeth (or else they are very flattened), but which still has cusplets present on the more lateral and posterior teeth [7].…”

“…The Middle Eocene shark tooth and coprolite-rich [10,11] sites in north-western Germany, which also contain few marine mammals, recently became important following the discovery of the world's oldest seal remains with a femur and humerus fragment [12], and newest sirenians remains with a rib and vertebra fragments [13]. Only 1% are such mammals, and 99% of the vertebrates Figure 1.…”

“…Global distribution of Middle Eocene (Lutetian) megatooth sharks and white sharks, and their migratory marine mammal prey. Seals were hunted along the beaches of the southern proto North Sea Basin, especially north of Osnabrück (palaeogeography of the Midlde Eocene and important fossil sites of Europe compiled from [10,12,13]).…”

Rare Late Miocene Seal Taxa (Carnivora, Phocidae) from the North Sea Basin

“…Th ese new and diverse assemblages consist mainly of cetaceans and late Miocene phocid pinnipeds. Although only three genera are discussed here, the actual diversity of fossil seals is much higher (Schneider, Heissig, 2005;Koretsky, Peters, 2008;Diedrich, 2011;Koretsky et al, 2012).…”