Fossil cercopithecidae from the Middle Pleistocene Dawaitoli formation, Middle Awash valley, Afar region, Ethiopia

Abstract

A series of fossil cercopithecoids has been recovered from the Dawaitoli Formation, in the Middle Awash study area, Ethiopia. The Dawaitoli Fm. has been dated to approximately 600 Ka. This series includes several partial crania of Theropithecus oswaldi leakeyi as well as other cranial and postcranial fragments. This material is some of the most complete to date and adds considerably to what is known of this widespread and abundant taxon. There are also two isolated papionin molars here allocated to Papio cf. hamadryas based largely on size grounds and similarity to contemporary material from other sites in the Afar Depression. Cercopithecoids are rare in the Dawaitoli Fm., and among them only large papionins are known. This is unique among known Pleistocene sites in the Afar region, but is most similar to the Daka Member of the Bouri Formation. It is quite different from the other known Middle Pleistocene sites in the Afar: Asbole and the geologically younger Andalee where cercopithecoids are abundant and colobines predominate.

Fossilpapiocranium from !Ncumtsa (Koanaka) Hills, western Ngamiland, Botswana

“…This specimen is quite similar to extant P. h. ursinus, but has larger teeth and stronger maxillary ridges (Broom, 1936;Freedman, 1957;Jablonski, 2002). is known from Middle Pleistocene sediments at Olduvai Gorge, Tanzania (Remane, 1925), and from Asbole and Bodo, Ethiopia (Alemseged and Geraads, 2000; Frost and Alemseged, 2007;Frost, 2007). A distal humerus and dP4 from the Upper Ndolanya Beds at Laetoli dating to 2.6 Ma are similar in morphology to Papio (Leakey and Delson, 1987) but more similar in size to Dinopithecus and cannot be reliably identified to genus at this point (Harrison, 2011).…”

“…indet. is known from Middle Pleistocene sediments at Olduvai Gorge, Tanzania (Remane, 1925), and from Asbole and Bodo, Ethiopia (Alemseged and Geraads, 2000;Frost and Alemseged, 2007;Frost, 2007). A few papionin specimens are also known from the Pliocene of East Africa but are not definitively Papio (Jablonski, 2002;Jablonski and Leakey, 2008).…”

New craniodental fossils of papionin monkeys from Cooper's D, South Africa

“… Previously published data from Freedman (, 1960), Singer (), Maier (), Dechow and Singer (), Leakey (), Delson and Hoffstetter (), Eck (), Frost and Alemseged (), Gilbert (), and Jablonski and Leakey ().L = length, max B = maximum breadth.…”

“…Male and female data are pooled, as not all teeth could be sexed. Data sources: T. o. darti from Makapansgat and Hadar; T. o. oswaldi from Swartkrans and Koobi Fora, Omo; T. o. leakeyi from Asbole and Hopefield (Freedman, ; Singer, ; Eck and Jablonski, 1987; Delson and Hoffstetter, ; Frost and Alemseged, ; Jablonski and Leakey, ).…”

“…The tooth is triangular and broad, unlike the narrow, elongate, dagger‐like canines of Papio . Theropithecus canines are relatively shorter and wider than in Papio and Gorgopithecus , and the distal edge of the tooth is not as sharp (Leakey and Whitworth, ; Delson and Hoffstetter, ; Frost, ), so this is likely T. o. oswaldi .…”