Miocene hominoids

Evolution of the hand in Miocene apes: implications for the appearance of the hu man hand de lo que me gustaría, siempre estáis ahí para lo que haga falta. Gracias por ser así, n o cambiéis nunca! A Carmen, Javier y Simona (aka 'padres y abuela del Alex') por ser una segunda família para mi, gracias por todo.

Explaining in simple terms the so-called aquatic ape theory.
Human ancestors during the Ice Ages (Pleistocene Homo after +-2 mill.yrs ago) did not disperse intercontinentally running over open plains as popularly assumed, but followed African & Eurasian coasts & rivers, where their diet included shallow-aquatic & waterside foods, which are rich in brain-specific nutrients, e.g. DHA, iodine, taurine, oligo-elements.

The hominoid cranium represents a tightly constrained, functionally and developmentally integrated structure subject to multiple selective influences. Modern apes are the remnant of a much more diverse radiation, raising issues about their suitability as models for earlier hominoids. Among gibbons the folivorous siamang is cranially distinctive. The markedly airorynchous Pongo is cranially highly variable and lacks the anterior digastric muscle, thereby contrasting with other hominoids except Khoratpithecus. African apes share a common cranial pattern differentiated by varying growth rates, not duration. Airorhynchy is common among fossil hominoids and differentiates hominoids from non-hominoids, suggesting African ape klinorhynchy is derived. Bonobos are cranially smaller, lighter, and less dimorphic than chimpanzees. These are comparatively uniform with extensive overlap between subspecies, whereas gorillas display considerable contrasts, especially between east and west populations. Early Miocene hominoids are already cranially diverse, with most species probably soft-or hard-fruit feeders. Middle and Late Miocene forms from Africa, Europe, and western Asia are thicker enameled with more strongly constructed crania suggesting harder diets, although Dryopithecus (soft frugivory) and Oreopithecus (folivory) are exceptions. South and East Asian fossil hominoids' diets ranged from soft fruits through harder items to bulky, fibrous vegetation. All extant ape crania are relatively lightly constructed compared with fossil forms, again prompting questions about their suitability for the adaptive modeling of earlier hominoids.

Biological reconstruction of ape and human (hominoid) evolution, mostly based on comparative, fossil, paleo-environmental and DNA evidence.

Schematically:

(I) arboreal to aquarboreal:
The evolution from monkey to ape body-plan is best explained by a transition from tree-dwelling to living in flooded forests (Mio-Pliocene).

(II) aquarboreal to littoral:
The evolution from ape/australopith to Homo body-plan can mostly be explained by a transition to a coastal and waterside lifestyle during the Ice Ages (early-Pleistocene dispersal along African and Eurasian coasts).

The Toumaï cranium TM 266 is the first known from any Late Miocene African hominoid clade, and is one of the best preserved crania of any Miocene hominoid. Since its publication there has been debate in the scientific literature and discussion in the popular press over the assertion that this cranium is significant because it is the earliest known hominid 1 . The basis of the hominid assessment rests on two interpretations of the anatomy: a hominid-like, small, flat-wearing canine; and, cranial features reflecting an upright stance and bipedal locomotion. In fact, it is widely reported that the specimen is an upright hominid biped , although this is yet to be verified by independent observations and study. The history of paleoanthropology may be relevant to this assessment, because there have been similar claims for other extinct primate species. Here, we evaluate the hypothesis that Sahelanthropus (the genus TM 266 is a�ributed to) is a hominid by examining features of the canine and of the cranial base that are said to reflect canine reduction and change of function, and upright posture and bipedal locomotion. These are hominid autapomorphies and their presence or absence in late Miocene hominoids has fundamental importance for identifying the hominid clade.

The Late Miocene sequence at Haritalyangar, Himachal Pradesh, India, has produced abundant remains of the hominid Sivapithecus and the sivaladapids Sivaladapis and Indraloris. Also recovered from these sediments is an isolated and worn upper molar that was made the holotype of Krishnapithecus krishnaii and assigned to the Pliopithecoidea. However, the heavy wear and absence of definitive pliopithecoid features on the tooth rendered the assignment to this superfamily unconvincing. Here, we describe two lower molars from Haritalyangar that bear unmistakable pliopithecoid features and that are plausibly assignable to the same species as the type specimen of K. krishnaii. They convincingly demonstrate for the first time the presence of the Pliopithecoidea in South Asia. The new molars also reveal that K. krishnaii was perhaps the largest known pliopithecoid and that it possessed highly derived postcanine dental morphology. Because of its highly derived nature, it is difficult to determine its relationships within Pliopithecoidea, but a sister taxon relationship with either the Dionysopithecidae or Pliopithe-cinae is equally plausible; it is only distantly related to the Crouzeliinae. It is sufficiently distinct, however , from all other pliopithecoids to warrant placement in a separate family.

The extensive outpouring of the Oligocene Trap basalts over eastern Africa and western Arabia was interrupted by a period of quiescence marked by the deposition of terrestrial sediments. These so-called intertrappean beds are often lignitiferous and yield recurrent floras and faunas, sometimes represented by endemic mammals. We intended to highlight the peculiar features of these sedimentary intercalations using a large-scale approach including eastern Africa and the western Arabian peninsula. Starting from a new mapping in the Eritrean highland, the intertrappean beds resulted a continuous level that was a few tens of meters thick and traceable for some tens of kilometers. They consist of fluvial red, green and gray mudstones and siltstones with subordinate channelized pebbly sandstones, and lignite seams. Two new 40Ar–39Ar datings constraint the age of the intertrappean beds between 29.0 Ma and 23.6 Ma. The outcrops near Mendefera have yielded the remains of two proboscidean families, the Deinotheriidae and the Gomphoteriidae. The morphological grade of the two Mendefera proboscideans would suggest a more derived stage than that of representatives of the same families from other Oligocene African sites (e.g., Chilga, Ethiopia). An Oligocene age could be inferred for them. The occurrence of the genus Prodeinotherium at Mai Gobro possibly represents the first occurrence of this taxon, while the Gomphotheirum sp. might represent the oldest occurrence of this taxon in Africa before its dispersal towards Asia and Europe. Proboscideans have also been found in the lowland intertrappean beds of Dogali near Massawa. These sediments were contiguous with the Eritrean highland intertrappean beds during the Oligocene, but are now tectonically displaced from them by two thousand meters of vertical topographical distance. Dogali is also known for the occurrence of possible Deinotheriidae remains and the primitive elephantoid Eritreum. Entering the Ethiopian highland, an inspection of the Agere Selam (Mekele) intertrappean beds revealed the occurrence of lacustrine limestones and diatomites, which were contrastingly quite subordinate with respect to the fine clastic sediments found in the nearby Amba Alaji area. Further south, the intertrappean section in the Jema valley (100 km north of Addis Ababa and close to the Blue Nile gorge) is 120 m thick with predominant clastic sediments and a few diatomite's at the top. Literature information from 35 additional sites, including northern Kenya, Yemen, Sudan and Saudi Arabia sections, confirms the fluvial and lacustrine depositional environment of the intertrappean beds, underlines the interest in their mammal fauna (Chilga, Losodok), and reports exploitable coal seams for some of them. As for the vegetal landscape in which the intertrappean beds were deposited, pollen and plant analysis results indicative of a tropical wet forest, similar to that of present-day western Africa. Another common feature of the intertrappean beds is their relatively limited thickness, averaging a few tens of meters, but reaching a few hundred meters in graben-related basins, such as Delbi Moye in southern Ethiopia. In most cases only thin, lens-shaped successions were deposited above the hummocky topography of their volcanic substratum, commonly unaffected by significant faulting. An average duration of the intertrappean beds is from one to three million years. This time interval is commonly matched by a few tens (or more rarely, hundreds) of meters of sediments left over after erosive episodes or depositional starvation. As to the lateral continuity of the intertrappean beds, the present-day outcrops show large differences: from some tens of kilometers in the Mendefera area, to a few tens of kilometres in the Jema valley, and to a few hundreds meters in the Agere Selam (Mekele) area. Even if it is difficult to quantify the original size of the sedimentation areas, it nevertheless proves that the intertrappean basins exceed thousands of square kilometers in only a single case (Mendefera), but were quite restricted in most cases. Their most likely endorheic and local character, together with a regional ill-defined fluvial network, was the effect of a water-course rerouting caused by the progressive rising of the eastern African and Arabian plateaux. Chronological constraints for the intertrappean beds can be inferred from the age of the hosting Trap succession and by the stratigraphical position that they occupy. Intervolcanic sedimentary episodes are typically found in the basaltic and subordinately rhyolitic successions that followed the 31–29 Ma old basaltic widespread paroxysm. With due caveats deriving from the discontinuous availability of datings specifically dedicated to this issue, we regard the age of the intertrappean beds as mostly encompassed in the interval from 29 to 27 Ma at the transition between the Early and Late Oligocene in the Ethiopia/Yemen Trap core. In marginal areas, such as SW Arabia, Eritrea and Kenya, the volcanic activity above the intertrappean beds resumed later, and its quiescence allowed a more prolonged period of sedimentation. The intertrappean beds fall in the second cooling event of the Oligocene climatic deterioration. During the contemporaneous apparent drop in the global sea-level and closure of the Tethyan Ocean between Arabia and southwestern Asia, connections were established between the African and the Eurasian continents. At that time, southwestern Asia was experiencing severe aridity with faunal exchanges toward the luxuriously vegetated eastern Africa.

This paper presents a reassessment of the taxonomic and phylogenetic affinities of the fossil catarrhine primates from the important middle Miocene site of Fort Ternan in Kenya. Although the sample of specimens is rather small, the material can be attributed to at least five different species, identified here as Kenyapithecus wickeri, Proconsul sp., a large species of oreopithecid, Simiolus sp., and a small species of catarrhine of indeterminate status. Kenyapithecus wickeri probably represents a conservative sister-taxon of the extant large hominoids. It is more derived than "Sivapithecus" africanus from Maboko Island, from which it can be distinguished at the generic level. A small species of catarrhine from Fort Ternan can be attributed to Simiolus. It is probably a different species from Simiolus enjiessi from the early Miocene of East Africa, but additional material is needed to confirm its taxonomic distinctiveness. The occurrence of at least five species of catarrhine primates at Fort Ternan confirms that species diversity levels were as high during the middle Miocene as they had been during the early Miocene. However, the overall taxonomic and ecological composition of the middle Miocene catarrhine community was quite different, evidently due to a significant change in the local ecological setting. Taxonomic differences between the catarrhine faunas at Fort Ternan and Maboko Island can probably be explained as a consequence of a chronological separation between the two sites, and, to a lesser degree, to paleoecological differences.

Here we describe the pelvis from the holotype specimen of Pierolapithecus catalaunicus (IPS-21350), a middle Miocene (11.9 Ma [millions of years ago]) stem hominid from Barranc de Can Vila 1 in Abocador de Can Mata (Catalonia, Spain) for which a partial skeleton is preserved. This skeleton includes the oldest known great ape pelvic materials, which have implications for reconstructing the basal hominid body plan from which later hominids evolved. The P. catalaunicus pelvis is composed of a fragment from the ilium (IPS-21350.38) and one from the ischium (IPS-21350.39). Although the P. catalaunicus ischium consists of just a small fragment from the caudal acetabulum, the preserved morphology is consistent with the basal hominoid Proconsul nyanzae. The ilium is similar to Pr. nyanzae in its concave gluteal surface and linea arcuata form, which suggests much of the iliac and pubic form was primitive. However, the ilium was relatively more flaring than Pr. nyanzae and most monkeys, and could be within the range of extant lesser apes. In addition, the iliac tuberosity width was probably intermediate between extant great apes and monkeys, although maximum and minimum estimates could be accommodated within either group. The P. catalaunicus ilium reflects incipient modifications of the basal hominoid torso for the more frequent use of orthograde behaviors described for this taxon on the basis of other preserved anatomical regions, and also supports claims that extant ape pelvic morphology could be homoplastic given the hypothesized phylogenetic positions of Pierolapithecus.

Oreopithecus bambolii is a Late Miocene ape from Italy, first described in the late 19th century. Its interpretation is still highly controversial, especially in reference to its hand proportions and thumb morphology. In this study, the authors provide detailed descriptions of the available Oreopithecus pollical distal phalanx (PDP) specimens, as well as bivariate and multivariate morphometric analyses in comparison with humans, extant apes, selected anthropoid monkeys, and available Miocene PDP specimens. The multivariate results reveal two opposite poles on the hominoid PDP shape spectrum: on one side, a mediolaterally broad and dorsopalmarly short human PDP, and on the other side, the narrow and “conical” PDP of chimpanzees and orangutans. The authors contend that Oreopithecus exhibits intermediate PDP proportions that are largely primitive for hominoids because it shares morphological similarities with Proconsul. Furthermore, Oreopithecus displays a mediolaterally wide tuft for a hominoid, as well as a palmarly elevated attachment for a long tendon of a flexor muscle that is associated at its proximal edge with a proximal fossa and at its distal edge with an ungual fossa. These nonmetrical traits have been associated in humans with their capability to oppose and contact the proximal pads of the thumb and fingers, that is, pad-to-pad precision grasping. These traits reinforce previous studies that indicate a human-like thumb-to-hand length ratio compatible with pad-to-pad precision grasping in Oreopithecus. Although specific hand use is still unresolved in Oreopithecus, the results suggest enhanced manipulative skills (unrelated to stone tool-making) in this taxon relative to other (extant or fossil) hominoids

The morphology of the anterior dentition has received scant attention for purposes of taxonomic discrimination. Recently, however, lingual incisor morphology was used in differentiating several Miocene ape species and genera. This paper assesses the utility of this morphology for taxonomic discrimination by examining the nature and patterns of variation in lingual incisor morphology in extensive samples of modern chimpanzees, gorillas, orangutans, and gibbons. This paper documents discrete morphological traits on the lingual side of incisors. Trait frequencies are used in univariate and multivariate analyses to examine the apportionment of variation in species, subspecies, and populations. A correlation between lingual incisor traits, tooth dimensions, and sex attempts to determine if such factors affect the manifestation of traits. Finally, the findings are applied to understanding patterns of variation in the Miocene hominids. The study demonstrates that: 1) lingual incisor morphology differs substantially between the hylobatids and great apes; 2) variation in incisor traits is high within species, and most of it is found within local populations; and 3) incisor traits do not correlate significantly with incisor dimensions or sex. Species and to some extent subspecies of extant hominoids can be differentiated statistically using lingual incisor traits, but the frequency of traits such as continuous or discontinuous cingulum, or the presence or absence of pillars, differentiates them. Given this pattern of variation, I argue that it is necessary to assume and document similar patterns of variation in Miocene apes before incisor morphology is used for differentiating taxa. Am J Phys Anthropol, 2006. © 2005 Wiley-Liss, Inc.

Primate hands display a major selective compromise between locomotion and manipulation. The thumb may or may not participate in locomotion, but it plays a central role in most manipulative activities. Understanding whether or not the last common ancestor of humans and Pan displayed extant-ape-like hand proportions (i.e., relatively long fingers and a short thumb) can be clarified by the analysis of Miocene ape hand remains. Here we describe new pollical remains-a complete proximal phalanx and a partial distal phalanxfrom the middle/late Miocene site of Castell de Barberà (ca., 11.2-10.5 Ma, Vallès-Penedès Basin), and provide morphometric and qualitative comparisons with other available Miocene specimens as well as extant catarrhines (including humans). Our results show that all available Miocene taxa (in Wiley Online Library (wileyonlinelibrary.com).

The partial skeleton of Pierolapithecus, which provides the oldest unequivocal evidence of orthogrady, together with the recently described phalanges from Paşalar most likely attributable to Griphopithecus, provide a unique opportunity for understanding the changes in hand anatomy during the pronogrady/orthogrady transition in hominoid evolution. In this paper, we describe the Pierolapithecus hand phalanges and compare their morphology and proportions with those of other Miocene apes in order to make paleobiological inferences about locomotor evolution. In particular, we investigate the orthograde/pronograde evolutionary transition in order to test whether the acquisition of vertical climbing and suspension were decoupled during evolution. Our results indicate that the manual phalanges of Miocene apes are much more similar to one another than to living apes. In particular, Miocene apes retain primitive features related to powerful-grasping palmigrady on the basal portion, the shaft, and the trochlea of the proximal phalanges. These features suggest that above-branch quadrupedalism, inherited from stem hominoids, constituted a significant component of the locomotor repertories of different hominoid lineages at least until the late Miocene. Nonetheless, despite their striking morphological similarities, several Miocene apes do significantly differ in phalangeal curvature and/or elongation. Hispanopithecus most clearly departs by displaying markedly-curved and elongated phalanges, similar to those in the most suspensory of the extant apes (hylobatids and orangutans). This feature agrees with several others that indicate orang-like suspensory capabilities. The remaining Miocene apes, on the contrary, display low to moderate phalangeal curvature, and short to moderately-elongated phalanges, which are indicative of the lack of suspensory adaptations. As such, the transition from a pronograde towards an orthograde body plan, as far as this particular anatomical region is concerned, is reflected only in somewhat more elongated phalanges, which may be functionally related to enhanced vertical-climbing capabilities. Our results therefore agree with the view that hominoid locomotor evolution largely took place in a mosaic fashion: just as taillessness antedated the acquisition of an orthograde body plan, the emergence of the latter—being apparently related only to vertical climbing—also preceded the acquisition of suspensory adaptations, as well as the loss of primitively-retained, palmigrady-related features.

Both pliopithecoid and hominoid primates were widely distributed throughout Eurasia during the Miocene but are known to have coexisted at only a few localities. It has been speculated that their different habitat preferences permitted only minimal overlap under special environmental conditions. Here we study the context for pliopithecoid and hominoid co-occurrence by assessing taxonomicallybased palaeoecological diversity of associated fossil mammals and by direct ecometric analysis based on hypsodonty of mammalian herbivores. Our results show that pliopithecoids persistently inhabited more humid environments compared to the other primate groups studied, suggesting an inability to adapt to changing environmental conditions. The opportunity for hominoids and pliopithecoids to cooccur appears to have been restricted by niche conservatism in the latter group. Our study also indicates that direct ecometric analysis gives a better separation of the ecological preferences of these primate clades than do analyses of taxonomically-based community structure.

We describe a partial innominate, YGSP 41216, from a 12.3 Ma locality in the Siwalik Group of the Potwar Plateau in Pakistan, assigned to the Middle Miocene ape species Sivapithecus indicus. We investigate the implications of its morphology for reconstructing positional behavior of this ape. Postcranial anatomy of extant catarrhines falls into two distinct groups, particularly for torso shape. To an extent this reflects different although variable and overlapping positional repertoires: pronograde quadrupedalism for cercopithecoids and orthogrady for hominoids. The YGSP innominate (hipbone) is from a primate with a narrow torso, resembling most extant monkeys and differing from the broader torsos of extant apes. Other postcranial material of S. indicus and its younger and similar congener Sivapithecus sivalensis also supports reconstruction of a hominoid with a positional repertoire more similar to the pronograde quadrupedal patterns of most monkeys than to the orthograde patterns of apes. However, Sivapithecus postcranial morphology differs in many details from any extant species. We reconstruct a slow-moving, deliberate, arboreal animal, primarily traveling above supports but also frequently engaging in antipronograde behaviors. There are no obvious synapomorphic postcranial features shared exclusively with any extant crown hominid, including Pongo.

Here we describe the vertebral fragments from the partial skeleton IPS18800 of the fossil great ape Hispanopithecus laietanus (Hominidae: Dryopithecinae) from the late Miocene (9.6 Ma) of Can Llobateres 2 (Vall es-Pened es Basin, Catalonia, Spain). The eight specimens (IPS18800.5eIPS18800.12) include a fragment of thoracic vertebral body, three partial bodies and four neural arch fragments of lumbar vertebrae. Despite the retention of primitive features (moderately long lumbar vertebral bodies with slightly concave ventrolateral sides), these specimens display a suite of derived, modern hominoid-like features: thoracic vertebrae with dorsally-situated costal foveae; lumbar vertebrae with non-ventrallyoriented transverse processes originating from a robust pedicle, caudally-long laminae with caudallyoriented spinous process, elliptical end-plates, and moderately stout bodies reduced in length and with no ventral keel. These features, functionally related to orthograde behaviors, are indicative of a broad and shallow thorax with a moderately short and stiff lumbar region in Hispanopithecus. Despite its large body mass (ca. 39e40 kg), its vertebral morphology is more comparable to that of hylobatids and Ateles than to extant great apes. This is confirmed by our morphometric analyses, also indicating that Hispanopithecus most closely resembles Pierolapithecus and Morotopithecus among Miocene apes, whereas Proconsul and Nacholapithecus resemble pronograde monkeys. Only in a few features (craniocaudally short and transversely wide pedicles, transverse processes situated on the pedicle, and slight ventral wedging), Hispanopithecus is more derived towards the extant great ape condition than other Miocene apes. Overall, the vertebral morphology of Hispanopithecus supports previous inferences of an orthograde body plan with suspensory and climbing adaptations. However, given similarities with Ateles and the retention of a longer and more flexible spine than in extant great apes, the Hispanopithecus morphology is also consistent with some degree of above-branch quadrupedalism, as previously inferred from other anatomical regions.

We describe phalanges of the KNM-BG 35250 Nacholapithecus kerioi skeleton from the Middle Miocene of Kenya. Phalanges of N. kerioi display similarities to those of Proconsul heseloni despite their enhanced robusticity. They do not show highly specialized features as in living suspensory primates. However, N. kerioi manifests several distinctive features that are observed in neither living arboreal quadrupeds nor P. heseloni or P. nyanzae. The most remarkable of them is its phalangeal elongation. N. kerioi phalanges (particularly pedal) are as long as those of Pan despite its much smaller body size. While lengthened digits enable a secure grip of supports and are especially adaptive for grasping large vertical trunks, the skeletal and soft tissues are subjected to greater stress. Probably, strong selective pressures favored powerful hallucal/pollical assisted grips. Although this functional adaptation does not exclude the possible use of the terrestrial environment, arboreal behavioral modes must have been crucial in its positional repertoire. N. kerioi is distinguished from P. heseloni in the greater size of its manual phalanges over its pedal phalanges. These derived features of N. kerioi suggest positional modes supporting more weight on the forelimb, and which occur more frequently on vertical supports. If Proconsul is referred to as an ''above-branch arboreal quadruped'' with a deliberate and effective climbing capability, N. kerioi may be thought of as an ''orthograde climber''. While living apes are powerful orthograde climbers, they are also more or less suspensory specialists. Suspensory behavior (plus climbing) and pronograde quadrupedalism (plus climbing) are the two main arboreal behavioral adaptations in living anthropoids. Thus, N. kerioi is an unusual fossil primate in that it cannot be incorporated into this dichotomy. It is plausible that a N. kerioi-like orthograde climber with large forelimbs and cheiridia was a precursor of suspensory living apes, and N. kerioi may demonstrate what an initial hominoid of this grade might have looked like.

In 1990, a new late Miocene locality named "Nikiti 1" or NKT, was discovered near the village of Nikiti (Chalkidiki, Macedonia, Greece) about 100 km east of Thessaloniki City. The locality is situated in the Nikiti Formation, which consists of yellowish sands, gravels and pebbles and has been dated to late Vallesian-early Turolian. Among the initially collected fossils there is a mandible of a hominoid primate, which is described, compared, and attributed to Ouranopithecus macedoniensis. A short review of the species in Macedonia and its phylogenetic relationships are also given.

The initial appearance of hominoids, or apes, and the selective pressures that led to their emergence are currently disputed. Central to the argument are the proconsulids, variously described as the earliest apes or as stem catarrhines, based on facial and postcranial data, respectively. The present paper reports on incongruence and parsimony analyses applied to a combined data set. The results demonstrate that proconsulids are cladistic hominoids, and that the apparent incongruence between the data sets is due to mosaic evolution; the earliest changes in Hominoidea occurred in the face. These results suggest that the initial divergence of hominoids involved selection for an ape-like face, and was not driven by an adaptive shift to below-branch locomotion.

Proconsul is one of the best-known catarrhine primates from the Miocene of eastern Africa. Most authorities consider it to be an early hominoid, but others contend that it might be a stem catarrhine (i.e., the sister group to Old World monkeys and apes) or a stem hominid (i.e., the sister group to great apes and humans) (Harrison 2010). Regardless of its precise phylogenetic affinities, it is evident from its cranio-dental and postcranial anatomy that Proconsul occupies an evolutionary grade close to the initial divergence of the apes and Old World monkeys, and that it provides a good model for the ancestral hominoid.

The Australopithecus afarensis partial skeleton A.L. 288-1, popularly known as “Lucy” is associated with nine vertebrae. The vertebrae were given provisional level assignments to locations within the vertebral column by their discoverers and later workers. The continuity of the thoracic series differs in these assessments,
which has implications for functional interpretations and comparative studies with other fossil hominins. Johanson and colleagues described one vertebral element (A.L. 288-1am) as uniquely worn amongst the A.L. 288-1 fossil assemblage, a condition unobservable on casts of the fossils. Here, we reassess the species attribution and serial position of this vertebral fragment and other vertebrae in the A.L. 288-1 series. When compared to the other vertebrae, A.L. 288-1am falls well below the expected size within a given spinal column. Furthermore, we demonstrate this vertebra exhibits non-metric characters absent in hominoids but common in large-bodied papionins. Quantitative analyses situate this vertebra within the genus Theropithecus, which today is solely represented by the gelada baboon but was the most abundant cercopithecoid in the KH-1s deposit at Hadar where Lucy was discovered. Our additional analyses confirm that the remainder of the A.L. 288-1 vertebral material belongs to A. afarensis, and we provide new level assignments for some of the other vertebrae, resulting in a continuous articular series of thoracic vertebrae, from T6 to T11. This work does not refute previous work on Lucy or its importance for human evolution, but rather highlights the importance of studying original fossils, as well as the efficacy of the scientific method.

The last twenty years have seen important findings in the area of paleoanthropology. The topic of man evolution fascinated scientist since Linnaeus (1758). The findings of several new genera and new species enabled the reconstruction of evolutionary trends. These trends lead to the identification of the unique living species Homo sapiens Linnaeus, 1758 (Hominidae: Homininae), starting from the splitting between Homininae and Paninae. The history of hominins' evolution was a very long one. During time the entire group took several evolutionary directions, showing an high adaptive capacity to the changes of the paleoenvironmental conditions.
Coppens (2013) provided an interesting sub-division of geological time using fossil of hominins. From geological and paleoecological settings, this author distinguished four temporal phases to re-arrange the chronostratigraphic distribution of species of Hominidae by correlating homologous part of fossils and by analyzing paleontological associations. Each phase is characterized by taxonomic and ecological homogeneity, bio-events and evolutionary degree of taxa belonging to a well defined phyletic lines (Palombo & Valli, 2003-04). Those groups may be considered a sort of continental biozones. The aim of this project is to demonstrate the validity of these phases as biozones marked by hominins.

Coppens Y. (2013) - Hominid evolution and the emergence of the genus Homo. In "Neurosciences and the Human Person: New Persperctives of Human Activities", Pontifical Academy of Science. Scripta varia, 121: 1-15.

Linnaeus C. (1758). Systema naturae per regna tria naturae, secundum classis, ordines, genera, species cum characteribus, differentiis, synonymis, locis. 10th ed. Vol. 1. Laurentii Salvii, Stockholm, Sweden.

Palombo M.R., Valli A.M.F. (2003-04) - Remarks on the biochronology of mammalian faunal complexes from the Pliocene to the middle Pleistocene in France. Geol. Romana, 37: 145-163.

Comparative analyses of molar shape figure prominently in Miocene hominoid evolutionary studies, and incomplete understanding of functional and phylogenetic influences on molar shape variation can have direct consequences for the interpretation of fossil taxa. Molar flare is a shape trait whose polarity, phylogenetic distribution, and functional significance have been sources of contention. To clarify the determinants of molar flare variation in the hominoid radiation, a combination of statistical methods was employed to investigate the effects of diet, phylogeny, and geologic age upon several measures of molar shape, to identify interactions among these factors, and to estimate their relative influence. Classic indices of molar crown shape and cusp relief are highly significantly associated with diet and show no clear phylogenetic or temporal patterning. Correlations with diet are insignificant when phylogenetic effects are controlled, a result which is interpreted as an artifact of the distribution of folivory in the Miocene hominoid radiation. Possession of pronounced molar flare was found to be the primitive condition for Miocene hominoids, but molar flare reduction cannot be considered a crown hominoid synapomorphy. Molar flare is strongly correlated with geologic age but differs significantly among dietary categories when the effects of time are controlled. Among contemporaneous taxa, hard-object feeders consistently show the highest levels of flare. Molar flare reduction is hypothesized to arise from realignment of cusp positions to maximize molar shearing and increase working occlusal surface area, while variation in flare among contemporaneous taxa may be due, at least in part, to enamel thickness variation. The pronounced molar flare of Otavipithecus is interpreted as a primitive retention, although alternative dietary and phylogenetic interpretations cannot be excluded. A dramatic reversal of molar flare reduction in Mio-Pliocene hominins is interpreted as a synapomorphy of the crown hominin clade, thus supporting the hominin status of the Lukeino hominine. The last common ancestor of the Pan-Homo clade is predicted to have possessed relatively non-flaring molars, and implications of this hypothesis for early hominin recognition are discussed.

VIII Encuentro de Jóvenes Investigadores en Paleontología VOLUMEN DE ACTAS Referencia a este artículo: Pérez de los Ríos, M., Moyà-Solà, S., Alba, D.M y Fortuny, J. Maxillary and frontal sinuses in Eurasian Miocene hominoids: phylogenetic implications. En: Moreno-Azanza, M., Díaz-Martínez, I., Gasca, J.M., Melero-Rubio, M., Rabal-Garcés, R. y Sauqué, V. (coords). Cidaris, número 30, VIII Encuentro de Jóvenes Investigadores en Paleontología, volumen de actas, 223-226.

The site of Loperot in West Turkana, Kenya, is usually assigned to the Early Miocene. Recent discoveries at Loperot, including catarrhine primates, led to a revision of its mammalian fauna. Our revision of the fauna at Loperot shows an unusual taxonomic composition of the catarrhine community as well as several other unique mammalian taxa. Loperot shares two non-cercopithecoid catarrhine taxa with Early Miocene

We describe the postcranial bones of a partial skeleton of a male infant Nacholapithecus kerioi (KNM-BG 37800) from the Middle Miocene of Kenya. The skeletal elements are associated with dental remains and its age is presumed to be 6-15 months based on a comparison with an infant Proconsul heseloni with a similar dental growth stage. The postcranial elements include the left scapula, a lumbar vertebra, left distal humerus, right proximal ulna, right radius, right and left proximal femora, a proximal fragment of metatarsal, and proximal and intermediate phalanges. Its body mass was estimated as 3.0 kg from shaft dimensions of the humerus and femur. At this early postnatal developmental stage, N. kerioi can be distinguished from P. heseloni in several postcranial features: a caudally projecting lumbar spinous process, strong dorsal divergence of the scapular spine, a coronoid fossa which is more developed than the radial fossa, higher neck shaft angle of the femur, taller trochlea of phalanges, and a lower brachial index. These features, except for the last, agree with the previously proposed positional behavioral reconstruction of N. kerioi, in which vertical climbing, orthograde clambering, transferring, or bridging are relatively important compared with P. heseloni. The apparently low brachial index results from a comparatively short radius for the predicted body mass. This might imply a relatively slow pace of growth in the radius of N. kerioi. However, it might result from body mass overestimation, incorrect length reconstruction, or individual variation. Its interpretation must await further specimens.

For over a century, a Neogene fossil mammal fauna has been known in the Irrawaddy Formation in central Myanmar. Unfortunately, the lack of accurately located fossiliferous sites and the absence of hominoid fossils have impeded paleontological studies. Here we describe the first hominoid found in Myanmar together with a Hipparion (s.l.) associated mammal fauna from Irrawaddy Formation deposits dated between 10.4 and 8.8 Ma by biochronology and magnetostratigraphy. This hominoid documents a new species of Khoratpithecus, increasing thereby the Miocene diversity of southern Asian hominoids. The composition of the associated fauna as well as stable isotope data on Hipparion (s.l.) indicate that it inhabited an evergreen forest in a C3-plant environment. Our results enlighten that late Miocene hominoids were more regionally diversified than other large mammals, pointing towards regionally-bounded evolution of the representatives of this group in Southeast Asia. The Irrawaddy Formation, with its extensive outcrops and long temporal range, has a great potential for improving our knowledge of hominoid evolution in Asia.

For over a century, a Neogene fossil mammal fauna has been known in the Irrawaddy Formation in central Myanmar. Unfortunately, the lack of accurately located fossiliferous sites and the absence of hominoid fossils have impeded paleontological studies. Here we describe the first hominoid found in Myanmar together with a Hipparion (sl) associated mammal fauna from Irrawaddy Formation deposits dated between 10.4 and 8.8 Ma by biochronology and magnetostratigraphy. This hominoid documents a new species of ...

Most human-like features in australopiths (thick tooth enamel, smaller canine teeth, not-elongated arms-hands-fingers, not-elongated iliac blades, flat & short-toed feet, long & strong big-toes etc.) are not human-derived, but are hominid-primitive ("hominid" sensu African hominoids, versus "pongid" sensu Asian great apes), or even hominoid-primitive (Verhaegen 1993, 1995). This means that there are no scientific arguments to exclude the australopiths from being closer relatives of Gorilla or Pan than of Homo. This explains the remarkable paradox that most paleo-anthropologists believe that the African apes have few or no fossils, whereas they generally agree that the Asian great apes do have a lot of fossils (e.g. Siva-, Lufeng-, Khorat-, Giganto-pithecus).

New early Miocene forelimb fossils have been recovered from the Songhor and Lower Kapurtay localities in southwestern Kenya. We describe four specimens that are similar in size and functional capabilities. Their specific allocation is problematic but these forelimb specimens must belong to either Rangwapithecus gordoni or Proconsul africanus. If these new postcranial specimens should belong to R. gordoni, on the basis of size and common dental specimens found at Songhor, they represent a new elbow complex. The morphology of these fossils is anatomically and functionally similar to that of Proconsul. The proconsuloid elbow complex allows extensive forelimb rotations and is capable of performing arboreal quadrupedalism and climbing activities. No suspensory adaptations are apparent. The proconsuloid elbow complex remains a good ancestral condition for hominoid primates.

For over a century, a Neogene fossil mammal fauna has been known in the Irrawaddy Formation in central Myanmar. Unfortunately, the lack of accurately located fossiliferous sites and the absence of hominoid fossils have impeded paleontological studies. Here we describe the first hominoid found in Myanmar together with a Hipparion (s.l.) associated mammal fauna from Irrawaddy Formation deposits dated between 10.4 and 8.8 Ma by biochronology and magnetostratigraphy. This hominoid documents a new species of Khoratpithecus, increasing thereby the Miocene diversity of southern Asian hominoids. The composition of the associated fauna as well as stable isotope data on Hipparion (s.l.) indicate that it inhabited an evergreen forest in a C3-plant environment. Our results enlighten that late Miocene hominoids were more regionally diversified than other large mammals, pointing towards regionally-bounded evolution of the representatives of this group in Southeast Asia. The Irrawaddy Formation, with its extensive outcrops and long temporal range, has a great potential for improving our knowledge of hominoid evolution in Asia.

We describe a partial innominate, YGSP 41216, from a 12.3 Ma locality in the Siwalik Group of the Potwar Plateau in Pakistan, assigned to the Middle Miocene ape species Sivapithecus indicus. We investigate the implications of its morphology for reconstructing positional behavior of this ape. Postcranial anatomy of extant catarrhines falls into two distinct groups, particularly for torso shape. To an extent this reflects different although variable and overlapping positional repertoires: pronograde quadrupedalism for cercopithecoids and orthogrady for hominoids. The YGSP innominate (hipbone) is from a primate with a narrow torso, resembling most extant monkeys and differing from the broader torsos of extant apes. Other postcranial material of S. indicus and its younger and similar congener Sivapithecus sivalensis also supports reconstruction of a hominoid with a positional repertoire more similar to the pronograde quadrupedal patterns of most monkeys than to the orthograde patterns of apes. However, Sivapithecus postcranial morphology differs in many details from any extant species. We reconstruct a slow-moving, deliberate, arboreal animal, primarily traveling above supports but also frequently engaging in antipronograde behaviors. There are no obvious synapomorphic postcranial features shared exclusively with any extant crown hominid, including Pongo.