Middle Pleistocene fossil Cercopithecidae from Asbole, Afar Region, Ethiopia

A sample of 117 fossil cercopithecids has been collected from the Middle Pleistocene site of Asbole, Afar Region, Ethiopia. A minimum of five species is present. There are two species of Cercopithecini, here recognized as cf. Chlorocebus aff. aethiops, and cf. Chlorocebus cf. patas. There are also two species of Papionini: Papio hamadryas ssp. indet. and Theropithecus oswaldi leakeyi. Finally, there is a single species of colobine present, Colobus sp. indet. The assemblage is chronologically constrained and is derived from sediments dated to approximately 600 ka. Within this sample Colobus sp. is by far the most common species present, outnumbering the other four species combined. The cercopithecid assemblage is most consistent with a woodland habitat, corroborating an earlier interpretation based on the non-primate fauna. Taxonomic, biogeographic, and evolutionary implications of the assemblage are also discussed.     

Partial cranium of Cercopithecoides kimeui Leakey, 1982 from Rawi Gully, southwestern Kenya

The Rawi Gully, located on the Homa Peninsula in southwestern Kenya, has produced several fossil elements of a large cercopithecid from sediments approximately 2.5 million years old (Ma). Nearly all of these elements appear to represent a single adult male individual of the colobine species Cercopithecoides kimeui Leakey, 1982. Part of the face, mandible, dentition, and several small postcranial fragments were collected by the Homa Peninsula Paleoanthropological Project (HPPP) in 1994 and 1995. This individual also appears to be represented by material collected in two previous expeditions to the site, one led by David Pilbeam in the 1970s and an earlier expedition led by L.S.B. Leakey in 1933. This specimen may extend the first appearance of C. kimeui by approximately 500 Kyr, and provides the first evidence for much of the male facial morphology in this species. Furthermore, Rawi may represent a more wooded habitat than the other occurrences of C. kimeui at Olduvai Gorge, Tanzania, and Koobi Fora, Kenya, indicating that C. kimeui may have been relatively flexible in its habitat preferences.     

Molar microwear and dietary reconstructions of fossil cercopithecoidea from the Plio-Pleistocene deposits of South Africa

The South African Plio-Pleistocene cave deposits have yielded a diverse cercopithecoid fauna. In this study, the possible dietary proclivities of these extinct species are examined using details of molar microwear. Although sample sizes are often small, wear patterns suggest possible temporal changes in the diets of Parapapio jonesi from Makapansgat to Sterkfontein, of Papio robinsoni from Sterkfontein to Swartkrans, and Cercopithecoides williamsi from Makapansgat to Sterkfontein to Swartkrans. However, there does not appear to have been a significant change in the dietary habits of Parapapio broomi over time. The microwear patterns of the two temporally successive congeners, Theropithecus darti and T. oswaldi show no significant differences from one another. The sympatric congeners, Parapapio broomi and Pp. jonesi, have microwear signatures that differ significantly at Makapansgat (Members 3 and 4) but not at Sterkfontein (Member 4). Finally, the microwear analyses suggest that the extinct cercopithecoid species did not necessarily have diets similar to those of their closest living relatives.     

Paranasal pneumatization in extant and fossil Cercopithecoidea

Unlike most primates, extant cercopithecoids lack maxillary sinuses, which are pneumatic spaces in the facial skeleton lateral of the nasal cavity proper. Character state analysis of living cercopithecoids across well-supported topologies suggests that the sinus was lost at the origin of the superfamily, only to have evolved again convergently in extant macaques. Recent work has shown that a) the 'early loss' hypothesis is supported by the lack of any pneumatization in Victoriapithecus, a stem cercopithecoid, b) like extant macaques, the fossil cercopithecine Paradolichopithecus shows evidence of presence of the maxillary sinus (MS), and c) unlike extant colobines, the fossil colobine Libypithecus also possesses a maxillary sinus. To more fully assess the pattern of cercopithecoid sinus evolution, fossil taxa from both subfamilies (Colobinae, Cercopithecinae) were examined both visually and by computed tomography (CT). The observations were evaluated according to standard anatomical criteria for defining sinus spaces, and compared with data from all extant Old World monkey genera. Most taxa examined conformed to the pattern already discerned from extant cercopithecoids. Maxillary sinus absence in Theropithecus oswaldi, Mesopithecus, and Rhinocolobus is typical for all extant cercopithecids except Macaca. The fossil macaque Macaca majori possesses a well-developed maxillary sinus, as do all living species of the genus. Cercopithecoides, on the other hand, differs from all extant colobines in possessing a maxillary sinus. Thus, paranasal pneumatization has reemerged a minimum of two and possibly three times in cercopithecoids. The results suggest that maxillary sinus absence in cercopithecoids is due to suppression, rather than complete loss.     

A reappraisal of the locomotion and habitat preference of Theropithecus oswaldi

The one modern member of the genus Theropithecus, T. gelada (Primates, Cercopithecidae), inhabits grassland and is highly terrestrial. It is often supposed that Theropithecus oswaldi, one of the most common primates of the Plio-Pleistocene of East and southern Africa, was also a highly terrestrial open habitat species. Ecomorphic analysis was used to assess the locomotor strategy and habitat preference of T. oswaldi, and it was found that this species was unlikely to have had a locomotor strategy and habitat preference identical to that of T. gelada, with T. oswaldi possibly using arboreal substrates in a manner similar to some modern baboon groups. Thus, it appears that there has been considerable ecological diversity in the genus Theropithecus over the course of its evolution, mirroring the diversity evident in the hominin fossil record.     

Fossil Cercopithecidae from the Middle Pleistocene Dawaitoli Formation, Middle Awash Valley, Afar region, Ethiopia

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.     

Biogeochemical and craniometric investigation of dietary ecology, niche separation, and taxonomy of Plio-Pleistocene cercopithecoids from the Makapansgat Limeworks

Three sympatric fossil cercopithecoid genera (Cercopithecoides, Parapapio, and Theropithecus) occur in Members 3 and 4 at the Makapansgat Limeworks hominin locality, South Africa, and their presence in a single ecosystem suggest a certain degree of ecological and/or dietary differentiation between taxa. Here, we explore the extent of dietary niche separation amongst these taxa using stable isotope (13C/12C, 18O/16O) and trace-element (Sr, Ba, Ca) analyses of fossil tooth enamel. In particular we searched for evidence of subtle niche separation between the more closely related, morphologically similar taxa of the genus Parapapio, as uncertainties exist around their taxonomy and taxonomic identification. Given these uncertainties, craniometric analyses were also performed to ground the dietary interpretations in a morphological context. The results found no clear taxonomic signal in the craniometric data for the Parapapio sample, and further indicate that this sample was no more variable morphologically than a single, geographically circumscribed, extant chacma baboon sample. In contrast, two overlapping dietary ecologies were found within this same Makapansgat Parapapio sample. Additionally, two widely differing dietary ecologies were found within the Cercopithecoides williamsi sample, while results for Theropithecus darti indicate a predominantly C4 diet. Hence, although biogeochemical dietary indicators point towards distinct dietary ecologies within and between fossil genera at Makapansgat, within the genus Parapapio disjunctions exist between the dietary categories and the taxonomic assignment of specimens.     

Cercopithecidae from the Pliocene Chiwondo beds, Malawi-rift

There are a total of 16 fossil cercopithecid specimens, representing at least 10 individuals, from the Chiwondo Beds of northern Malawi. The majority of this material is derived from the Middle Pliocene Unit 3A, but one specimen is from the Early Pliocene Unit 2. This latter specimen is from a papionin of indeterminate genus similar in size to Parapapio ado and Pliopapio alemui. Among the specimens from Unit 3A, two species can be diagnosed: an indeterminate species of Theropithecus, and a species of Parapapio similar in dental size to P. broomi. Neither of the genera from Unit 3A are exclusive to either East Africa or South Africa. Their relative abundances, however, are more similar to Middle Pliocene South African sites where Parapapio is the most common primate genus, and Theropithecus is comparatively rare. This is in contrast to similarly-aged East African sites where Theropithecus is by far the most abundant genus.     

Theropithecus and 'Out of Africa' dispersal in the Plio-Pleistocene

Theropithecus oswaldi was one of the most widely distributed Plio-Pleistocene primates, found in southern, East, and North Africa, as well as in Spain, India, and possibly Italy. Such a large geographic range for a single primate species is highly unusual. Here, the nature and timing of its dispersal is examined using the Stepping Out cellular automata model. A hypothetical dispersal of T. darti is also modelled to assess whether the late Pliocene might have been a more favorable period for Afro-Eurasian dispersal than the early Pleistocene. Stepping Out draws on climatic and biome reconstruction to provide the paleovegetative and climatic background necessary for the simulations, and model parameters for T. oswaldi and T. darti were set a priori on the basis of their fossil records and paleobiologies. The simulations indicate that T. darti could have readily left Africa in the Pliocene, and that it swiftly reaches Asia. A European T. darti colonization was less certain and less rapid. The simulated T. oswaldi dispersal out of Africa was slower, but nonetheless T. oswaldi arrived at Mirzapur within the time period indicated by the fossil record. Using the a priori parameters, T. oswaldi did not arrive at the European sites of Cueva Victoria and Pirro Nord. It cannot be discounted, therefore, that some of the European fossils are a result of an earlier T. darti dispersal. The simulations also showed that in order for Theropithecus to reach Europe, it needed to be tolerant of a relatively wide range of habitats. In addition, our finding that Asian colonization was more rapid and more probable parallels the information from the hominin fossil record, in which the fossils from Asia predate those from Europe by several hundred thousand years.     

New species of Cercopithecoides from Haasgat, North West Province, South Africa

Analyses of new cercopithecid fossil specimens from the South African site of Haasgat point to craniofacial affinities with the genus Cercopithecoides. Detailed metric and non-metric comparisons with South African Cercopithecoides williamsi, and other East African Cercopithecoides species, Cercopithecoides kimeui, Cercopithecoides meaveae, Cercopithecoides kerioensis, and Cercopithecoides alemyehui demonstrate that the Haasgat fossils have distinct craniofacial morphology and dental metrics. Specifically, material from Haasgat probably represents one of the smaller Cercopithecoides, differing from the others in its particular suite of features that vary within the genus. It is unique in its more vertical ramus, associated with a relatively lengthened mandibular body. Haasgat Cercopithecoides has a particularly narrow interorbital region between relatively larger ovoid orbits, with articulation of the maxillary bones at a suture above the triangular nasal bones. Furthermore, the maxillary arcade is more rounded than other Cercopithecoides, converging at the M² and M³. The conclusion drawn from this analysis is that the Pleistocene Haasgat fossils are colobines representing a distinct taxon of Cercopithecoides, Cercopithecoides haasgati, thus adding a second species of the genus to southern Africa.     

A new large Pliocene colobine species (Mammalia: Primates) from Asa Issie, Ethiopia

The Colobinae (Mammalia: Primates) are relatively unknown from the African middle to late Miocene. When they appear in the Pliocene they are unambiguous and already fairly diverse taxonomically, geographically, and ecologically. Discoveries from Pliocene sediments in eastern and southern Africa document a radiation of large-bodied colobines very different from those known today. Paleontological research in Ethiopia has recently led to the discovery and identification of another large-bodied colobine species from the early Pliocene site of Asa Issie, discovered in 2000. This new colobine is larger than but morphologically very similar to its sister taxon Kuseracolobus aramisi, an older taxon also described from the Middle Awash. This new species has significant implications for our understanding of the Pliocene colobine adaptive radiation.     

Extinct large colobines from the Plio-Pleistocene of Africa

Three genera and six species of extinct African Plio-Pleistocene Colobinae are discussed. One new genus, Rhinocolobus and three new species, R. turkanaensis, Cercopithecoides kimeui and Paracolobus mutiwa are named. These colobines show a diversity in postcranial and dental morphology not seen among extant species. Rhinocolobus was most similar to extant Colobus in postcranial morphology and had similar high-cusped shearing teeth. Cercopithecoides shows a number of postcranial skeletal features typical of terrestrial cercopithecid species and has lower cusped teeth. Paracolobus, while generally more similar to Rhinocolobus than to Cercopithecoides, is intermediate in some features of its postcranial morphology. The distribution of the various taxa among East and South African sites with different palaeoenvironments is generally consistent with the morphological interpretation. With the exception of Cercopithecoides kimeui, which persisted a little longer, these large colobines disappear from the fossil record about 1.8 million years ago. Their disappearance coincides with an interval of increasing aridity documented at Olduvai Gorge, the Omo Valley, and East Turkana.     

Miocene cercopithecoidea from the Tugen Hills, Kenya

Miocene to Pleistocene fossiliferous sediments in the Tugen Hills span the time period from at least 15.5 Ma to 0.25 Ma, including time periods unknown or little known elsewhere in Africa. Consequently, the Tugen Hills deposits hold the potential to inform us about crucial phylogenetic events in African faunal evolution and about long-term environmental change. Among the specimens collected from this region are a number of discoveries already important to the understanding of primate evolution. Here, we describe additional cercopithecoid material from the Miocene deposits in the Tugen Hills sequence, including those from securely dated sites in the Muruyur Beds (16-13.4 Ma), the Mpesida Beds (7-6.2 Ma) and the Lukeino Formation (∼6.2-5.7 Ma). We also evaluate previously described material from the Ngorora Formation (13-8.8 Ma). Identified taxa include Victoriapithecidae gen. et sp. indet., cf. Parapapio lothagamensis, and at least two colobines. Specimens attributed to cf. Pp. lothagamensis would extend the species’ geographic range beyond its type locality. In addition, we describe specimens sharing derived characters with modern African colobines (Tribe: Colobina), a finding that is congruent with previous molecular estimates of colobine divergence dates. These colobine specimens represent some of the earliest known members of the modern African colobine radiation and, in contrast to previous hypotheses, suggest that early African colobines were mainly arboreal and that semi-terrestrial Late Miocene and Plio-Pleistocene colobine taxa were secondarily derived in their locomotor adaptations.     

The Hand of Cercopithecoides williamsi (Mammalia,Primates): Earliest Evidence for Thumb Reduction among Colobine Monkeys

Thumb reduction is among the most important features distinguishing the African and Asian colobines from each other and from other Old World monkeys. In this study we demonstrate that the partial skeleton KNM-ER 4420 from Koobi Fora, Kenya, dated to 1.9 Ma and assigned to the Plio-Pleistocene colobine species Cercopithecoides williamsi, shows marked reduction of its first metacarpal relative to the medial metacarpals. Thus, KNM-ER 4420 is the first documented occurrence of cercopithecid pollical reduction in the fossil record. In the size of its first metacarpal relative to the medial metacarpals, C. williamsi is similar to extant African colobines, but different from cercopithecines, extant Asian colobines and the Late Miocene colobines Microcolobus and Mesopithecus. This feature clearly links the genus Cercopithecoides with the extant African colobine clade and makes it the first definitive African colobine in the fossil record. The postcranial adaptations to terrestriality in Cercopithecoides are most likely secondary, while ancestral colobinans (and colobines) were arboreal. Finally, the absence of any evidence for pollical reduction in Mesopithecus implies either independent thumb reduction in African and Asian colobines or multiple colobine dispersal events out of Africa. Based on the available evidence, we consider the first scenario more likely.     

Occurrence of Theropithecus sp. in the Late Villafranchian of Southern Italy and implication for Early Pleistocene "out of Africa" dispersals

Three cervical vertebrae of a large primate have been identified in the revision of the faunal assemblage collected during the late '70s from fissure fillings in the area known as Pirro Nord in southern Italy. By size the three vertebrae are comparable to the large fossil species Theropithecus oswaldi, however we prefer here to attribute the remains to Theropithecus sp. The Pirro Nord Theropithecus represents the second finding outside of Africa of this genus in association with Megantereon whitei, after the site of 'Ubeidiya. The biochronology of Pirro Nord faunal assemblage demonstrates that the arrival into Europe of Theropithecus occurred earlier than thought: in the range of approx 1.6-1.3 Ma. The identification of an European "African assemblage" (Theropithecus associated with Megantereon whitei) has consequences for interpretation of an "out of Africa" (genus Homo) event around the Plio-Pleistocene transition.     

Additional fossil Theropithecus from Hopefield, South Africa: a comparison with other African sites and a reevaluation of its taxonomic status

Additional fossil Theropithecus remains, recovered from mid to late Pleistocene deposits near Hopefield , South Africa, include portions of the jaws of at least five individuals. Extensive comparisons with fossil Theropithecus from other African sites, including Makapan , Swartkrans , Kanjera , Olorgesailie , and Olduvai , reveal few morphological differences, especially when variation in modern gelada baboons ( Theropithecus gelada ) and savannah baboons (Papio) is considered. The most pronounced differences between fossil forms are overall size and relative P3 length. However, these traits do not separate the fossil forms either chronologically or geographically. Other traits, such as depth of the fossa of the mandibular corpus, slope of the upper symphyseal shelf, and variation in the depth of the mandibular corpus, do not distinguish alleged primitive forms ( Makapan and lower beds at Olduvai ) from remains found at Hopefield , Swartkrans , Kanjera , Olorgesailie , Olduvai Bed IV, or the lower Ndutu Beds. Other traits, such as canine crown height and incisor size, are poorly documented for fossil Theropithecus . Thus, the available evidence suggests that Theropithecus darti and its successional species, T. oswaldi , can best be considered as a single fossil species, T. oswaldi , of which the remains from Hopefield are a late representative. Furthermore, lack of morphological differences dictates that Hopefield Theropithecus not be considered a distinct subspecies. Variation within the Hopefield sample shows that only one taxa is found at this site. Hypothesized physical and climatic conditions at Hopefield during the Pleistocene suggest that T. oswaldi lived near vleis or fresh water lagoons. Comparisons with modern T. gelada suggest a graminivorous diet for the fossil form.     

First discovery of colobine fossils from the early to middle Pleistocene of southern Taiwan

Here we report on two kinds of cercopithecid fossil monkeys (Cercopithecinae and Colobinae) from the early to middle Pleistocene sediments of the Chochen (=Tsochen) area (Tsailiao-chi or Shinhua Hill), southern Taiwan. The fossil specimens include the first fossil record of colobine monkeys from Taiwan, where only macaque monkeys now occur. All cercopithecine fossils were identified as Macaca cf. Macaca cyclopis, the extant Taiwan macaque, except for one extremely large isolated upper molar, which may belong to another macaque species. On the other hand, all colobine specimens fall within the size variation of extant and extinct Rhinopithecus, but its specific status cannot be determined because of the scantiness of the fossil material. In Taiwan, Rhinopithecus presumably became extinct in the late Pleistocene, probably owing to global cooling and vegetation change, whereas macaques, which are of almost the same body size as Rhinopithecus, survived as M. cyclopis to the present. The contrasting history of survival between the two kinds of monkeys may be due to ecological/behavioral differences between them or as a result of accidental events that occurred in the Pleistocene of Taiwan.     

New rodents (Cricetidae) from the Neogene of Curaçao and Bonaire,Dutch Antilles

Cordimus, a new genus of cricetid rodent, is described from Neogene deposits on the islands of Curaçao and Bonaire, Dutch Antilles. The genus is characterized by strongly cuspidate molars, the presence of mesolophs in most upper molars and the absence of mesolophids in lower molars. Similarities with the early cricetid Copemys from the Miocene of North America coupled with apparent derived characters shared with the subfamily Sigmodontinae suggest that Cordimus may be close to the root of the sigmodontine lineage, a possibility that remains to be tested through explicit phylogenetic analysis. Three species are recognized on the basis of size and details of molar morphology. Cordimus hooijeri sp. nov. is described from Bonaire on the basis of Holocene owl pellet material that consists of dentaries and postcranial material only. This species is presumed to be extinct, but focused surveys are needed to confirm this hypothesis. Cordimus debuisonjei sp. nov. and Cordimus raton sp. nov. are described from deposits on Tafelberg Santa Barbara in Curaçao. Although the age of these deposits is not known, they are most likely of late Pliocene or early Pleistocene age. Both are represented by numerous isolated molars and some osteological material.