of the Duchesne River Formation, which has an age of approximately 39.74 ± 0.07 Ma based on radioisotopic dates from nearby volcanic ashes. Two localities within New Mexico yielded Brachyhyops material and include a single molar (m1) from the lower jaw that was assigned to B. viensis and recorded within the Duchesnean interval of the Galisteo Formation in north central New Mexico, and is of late Duchesnean (38 Ma) age. An additional specimen was recorded from the upper Baca Formation at Mariano Mesa in west central New Mexico and is also situated within the Duchesnean. This specimen comprises a single premolar and four molars (p3 – m4) from a single right lower jaw and are assigned to B. wyomingensis based on the shape and dimensions of the teeth. The final locality within North America is located in Trans-Pecos, Texas, USA, and contains well documented records of Brachyhyops wyomingensis from the late Duchesnean Porvenir local fauna which is situated above a volcanic ash that is radioisotopically dated to 37.8 ± 0.15 Ma. The fact that there is no stratigraphic overlap between northern and southern Asian Brachyhyops specimens, suggests that Brachyhyops originated in southern Asia during the early and late middle Eocene and continuously dispersed into northern Asia. Long term exposure of the Beringian land bridge during the late Eocene promoted continuous intercontinental dispersal from Asia into North America, resulting in further dispersal and diversification of Brachyhyops across western North America during the late Eocene. Diet The dentition of Brachyhyops is heterodont, which forms a complex set of different teeth including incisors, large canines, premolars, and molars, which are used to capture and process a wide variety of food items including both meat and vegetation. Despite their heterodont tooth condition, there has been a considerable amount of debate regarding the diet of Brachyhyops and various other entelodontids with similar dentition, such as Archaeotherium and Daeodon. Researchers have proposed different dietary hypotheses based on the heterodont dentition and shape of the teeth, interpreting entelodontids as rooting, pig-like omnivores, browsers or even active predators, based on wear grooves on their dentition. By studying well-preserved fossils, Joeckel re-evaluated these interpretations and performed several modeled analyses regarding the wear patterns on the dentition and structure of the skull (in particular the growth series and muscle reconstruction of the skull) and concluded an omnivorous diet for Archeaotherium, and most likely Brachyhyops, in which scavenging and active hunting