STABLE ISOTOPES ANALYSIS OF ARSINOITHERIUM AND ASSOCIATED FAUNA AND THE IMPLICATIONS ON BIOGEOGRAPHY

The aquatic lifestyle of Embrithopod mammals is unknown. Originally thought to have been either semi- or fully-aquatic, research completed by Clementz et. al. (2008) concluded that the Oligocene African embrithopod Arsinoitherium was actually a terrestrial mammal¹. It is important to understand if embrithopods in general were aquatic because it will shed light on how this group of African mammals eventually ended up on the Eurasian island of Pontides during the middle Eocene (Lutetian). Surrounded by the Paratethys and Neotethys seas, Eocene embrithopods inhabiting the Pontide terrane would have either had to employ an “island hopping” method or ride a land raft to the island. It is more likely based on morphology and the stratigraphic layers that the fossils are found in that embrithopods swam to Pontides. δ¹⁸O and δ¹³C analysis will be completed to test this theory. Low δ¹⁸O values, compared to a known terrestrial mammal from Paratethys, will indicate that Turkish Eocene embrithopods were aquatic mammals.

¹Clementz, M. T.; Holroyd, P. A.; Koch, P. L. Palaios 2008, 23(9), 574–585.