Materials
The primary data analyzed in this study derive from collections housed at the National Museums of Kenya and the National Museum of Ethiopia. The published record of fossil mammals from the Turkana Basin has been compiled into a database that uses FileMaker Pro software Bobe and Behrensmeyer, 2007 . The Turkana Basin Paleontology Database currently has about 16,500 records of fossil mammals from geological formations on both sides of Lake Turkana that span in time from the late Miocene to the...
UR Chiwondo Beds Uraha Malawi ca Ma
The geological age of this relatively complete mandibular body with teeth is uncertain. Although Bromage et al. 1995 settled on an age of 2.3-2.5 Ma for the specimen, the surface from which it comes contained a temporally mixed fauna with elements potentially ranging in age from approximately 3 Ma to less than 2 Ma K. Reed, pers. comm., 2007, considers the fauna to indicate an age of anywhere between 2.5 and 1.9 Ma . Notwithstanding doubts about its earliest status, the mandible has been...
Hypodigms of Early Homo
Although a case can be made for lumping all of the early Homo fossils together as members of a single highly dimorphic species Tobias, 1991 , there is agreement, reflected among workshop participants, that the resulting hypodigm is so variable that partitioning is warranted. Sorting the fossils to two or more groups has been done differently by a number of workers Groves, 1989 Wood, 1991, 1992 Rightmire, 1993 Blumenschine et al., 2003 , partly as a consequence of the varying emphasis placed on...
References Sul
Ashley, G.M., Hay, R.L., 2002. Sedimentary patterns in a Plio-Pleistocene volcaniclastic rift-margin basin, Olduvai Gorge, Tanzania. In Renaut, R.W., Ashley, G.M. Eds , Sedimentation in Continental Rifts. Volume 73 of SEPM Society for Sedimentary Geology Special Publication. SEPM, Tulsa, pp. 107-122. Baker, B.H., Mitchell, J.G., Williams, L.A.J., 1988. Stratigraphy, geo-chronology and volcano-tectonic evolution of the Kedong-Naivasha-Kinangop region, Gregory Rift Valley, Kenya. Journal of the...
Dental Topographic Analysis
Primate molar teeth are adapted to the fracture properties of foods consumed Lucas, 2004 . As Spears and Crompton 1996 have noted, dental morphology affects the nature, magnitude and distribution of stresses on food particles. Extant species known to consume tough foods, for example, have more occlusal relief than those adapted to eating hard, brittle objects e.g., Kay, 1984 Meldrum and Kay, 1997 Lucas, 2004 . Most studies to date have focused on unworn molar teeth usually M2s to allow...
New Interpretations of the Genus Homo GeneticsBased Interpretations
Morris Goodman and his colleagues have presented their interpretation of how hominin taxonomy should be adapted to reflect the recent molecular and genetic evidence suggesting a particularly close relationship between modern humans and chimpanzees Goodman et al., 1998, 2001 Wildman et al., 2003 . The only paleoanthropologists who have responded to these new data have been Groves 2001 , Cameron and Groves 2004 both reviewed above and Curnoe and Thorne 2003 . The conclusions of the latter study...
Maturation of the Teeth and Skeleton of KMNWT Basic Observations
To review briefly, the Nariokotome juvenile is judged to be male on the basis of sciatic notch morphology, skull robust-icity, and overall size of the skeleton Ruff and Walker, 1993 . KNM-WT 15000 certainly died at early adolescence, before reaching adult size and proportion of the axial and appendicular skeletons further he had most likely initiated, but not completed, physical and behavioral sexual maturation Table 9.7 in Smith, 1993 . Major ossification centers of long bone epiphyses had...
Early Homo Molars
The foregoing analyses support previous studies that have suggested molar cusp sizes to be of some utility in the assessment of the taxonomic affinities of hominin fossils Wood et al., 1983 Wood and Engleman, 1988 Suwa, 1988 Suwa et al., 1994, 1996 Bailey, 2004 . Accordingly, it is reasonable to employ such data in the assessment of the species attribution of the early Homo specimens from South Africa. However, because of the extremely small comparative fossil samples from East Africa, extreme...
Introduction Dgi
As aptly observed by Aiello et al. 2000 , any attempt to reconstruct human evolutionary history depends upon reliable hypotheses pertaining to the species groups that are represented in the hominin fossil record. There has been a notable lack of consensus regarding the species of Homo that are represented in the Plio-Pleistocene karst cave deposits of South Africa Howell, 1978 Clarke, 1977a, b, 1985a, b, 1994 Chamberlain, 1987 Rightmire, 1990 Wood, 1991 Tobias, 1991 Kimbel and Rak, 1993 Grine...
Discussion
Cusp area data for the permanent molars attributed to Homo from the sites of Swartkrans, Sterkfontein and Drimolen tend to suggest closer affinities with H. habilis than with H. erectus homologues from East Africa. At the same time, however, there is generally some degree of linkage among the South African fossils such that a number have closer affinities with one another than with East African specimens. When the South African specimens are considered as a separate unique group, relative...
Endurance Running and Hunting
Another key, perhaps even more important role for ER in H. erectus and possibly earlier Homo may have been during hunting. As noted above, a wide array of evidence suggests that hominins were actively hunting, at least by the time that H. erectus appears circa 1.9 Ma for reviews see Potts, 1988 Bunn, 2001 Dominguez-Rodrigo, 2002 . The evidence for hunting includes a large proportion of bones with cut-marks indicative of flesh removal from regions of shafts that would not have had flesh had they...
Dmanisi Homo erectus
There are numerous resemblances to Homo erectus. These include the low cranial profile, flattened frontal, sagittal keeling, reduced width of the parietal vault in relation to the cranial base, cresting at the parietal angle and mastoid region, shape of the temporal squama, angled occiput D2280, D3444 , depth and architecture of the mandibular fossa, and orientation of the petrous axis. In the elevation of the nasal saddle, lack of surface relief on the nasal sill, and posterior location of the...
Stature and Body Mass
Ruff and Walker 1993 note Nariokotome was a large individual indeed Nariokotome emerges as large even compared to all nine known adult early Homo specimens Table 11.15, KNM-ER 1472 KNM-ER 1481 KNM-ER 3728 KNM-ER 736 KNM-ER 1808 KNM-ER 737 OH 34 OH 28 and KNM-WT 15000 . The mean stature of these nine adult specimens is 162 cm 5' 4 and the mean body mass estimate 54 kg 119 lbs , both of which, however, include estimates for Nariokotome - and are not in fact far different from the estimates of...
Mean Dental Age
Smith 1993 assessed the stages of individual tooth formation in Nariokotome see also Brown and Walker, 1993 and compared them with those defined by Moorrees et al. 1963 and Anderson et al. 1976 . The average dental age for mandibular permanent teeth that are still forming is 10.3 years when scored against the standards of Moorrees et al. 1963 higher if one estimates a value for Mj the average of all ten immature mandibular and maxillary teeth is 10.6 years adding in values from Anderson et al....
Early Homo Samples
The proposal that two taxa, namely H. habilis and H. rudolfensis, can be distinguished among the fossils traditionally regarded as representing Homo habilis sensu lato is not universally accepted e.g., Suwa et al., 1996 Miller, 1991, 2000 Dunsworth and Walker, 2002 Lee and Wolpoff, 2005 . However, we believe that good evidence has been put forward favoring this distinction, regardless of how the hypodigms of these species are constructed Lieberman et al., 1988 Wood, 1991, 1992, 1993 Rightmire,...
KNMBC Chemeron Formation Kenya ca Ma
Hill et al. 1992 Sherwood et al., 2002 promoted this fragmentary temporal bone, found in 1966, as the earliest known example of the Homo lineage based mainly on the supposed extreme medial position of the mandibular fossa relative to the lateral wall of the braincase, which they thought reflected brain expansion, as well as several qualitative features of the glenoid region and petrous element tegmen tympani exposed in ceiling of mandibular fossa, anteromedial recess present, steep and...
Skeletal Age Versus Dental Age
Conservatively, skeletal age in Nariokotome was more than 2.5 years greater than his mean dental age SA - DA 13 - 10.2 2.8 years the discrepancy only rises if strictly African standards Table 10.2 Dental age of KNM-WT 15000 by human standards compared to ages of children in similar developmental stages in other samples LM2 R 1 2 Dental age mandibular teeth Dental age all Worldwide sample-boys Liversidge et al., 2006 gt 10.60 10.10 12.30 gt 9.90 10.20 10.00 10.50 10.50 10.30 10.60 Modern...
Scenarios for Evolution of Modern Human Shoulder Configuration
The observations summarized above indicate that a more protracted scapula with an anteriorly directed glenoid and low humeral torsion formed an intermediate stage between the more primitive condition of early hominins and the configuration of the pectoral girdle shoulder in modern humans. What might the stimulus have been for this latter change, returning the scapula to a more dorsal position so that the glenoid fossa faced laterally Fig. 7.4c , concomitantly requiring an increase in humeral...
Scaling of the Humerofemoral and Intermembral Indices
The relationship between body mass and humerus length is remarkably consistent among modern humans and African apes Jungers, 1994 . Humerus length divided by the cube root of body mass does not distinguish among gorillas, chimpanzees, bonobos, African Pygmies and larger-bodied humans rephrased in a slightly different manner, the interspecific log-log scaling relationship between these two variables is highly significant and isometric. This perhaps surprising result indicates that humerus length...
Early Hominins Scapula
Most interpretations of early hominin shoulder morphology have been based on two fossil scapular fragments STS 7 Broom et al., 1950 attributed to Australopithecus africanus, and A.L. 288-1l, Johanson et al., 1982 attributed to A. afarensis Table 7.1 . The feature that has received the most attention in functional analyses of these fossils is the orientation of the glenoid fossa. In hominoid primates the glenoid faces cranially reflecting the importance of overhead limb postures, while in modern...
Body Proportion and Stature
On first sight, the long limbs of Nariokotome set him apart from earlier hominins. As Ruff and Walker 1993 have shown, the distal segments of his limbs are particularly long. Both the crural tibia femur length x 100 and brachial radius humerus length x 100 indices for Nariokotome indicate an individual with tropical subtropical limb proportions. His crural index 88 as compared, for example, with 84.5 in the Denver growth sample of Ruff, 2007 is particularly extreme, falling 1 S.D. above the...
Age of Death from Microanatomy
Microanatomical studies of enamel and dentine are beginning to yield real estimates of the age of attainment of marker events in the life history of Homo erectus and other hominin species Bromage and Dean, 1985 Dean et al., 1993b, 2001 Smith et al., 2007a . In the best cases, thin sections of teeth can be analyzed to determine age of death, as well as the timing of certain stressful life history events, with an astonishing accuracy. Schwartz et al. 2006 Schwartz and Dean, 2008 were able to date...
History of Homo
The history of the interpretation of the genus Homo from its introduction in 1758 by Carolus Linnaeus in the tenth edition of his Systema Naturae to the inclusion in 1964 of Homo habilis, has been one of episodic relaxation of the criteria used for including taxa in Homo. Each of these episodes has resulted in one, or more, species being added to Homo. As originally conceived by Linnaeus, the genus Homo incorporated two species, Homo sapiens and Homo sylves-tris also called Homo troglodytes or...
Proximal Humerus
To the degree that it can be determined, the head of all known early hominin humeri is elliptical rather than spherical in shape as in apes, and the intertubercular groove is somewhat shallow, rather than deep and tunnel-like as in African apes. Broom et al. 1950 describe the STS 7 proximal humerus as basically humanlike, although the tubercles are somewhat distinct, with a more prominent lesser tubercle than typically seen in modern humans or great apes. The Chemeron proximal humeral fragment...
K 1
KNM-ER 739, 66 KNM-ER 806, 124 KNM-ER 820, 114 KNM-ER 992, 3, 124, 126 KNM-ER 1470, 3, 4, 19, 32, 33, 35, 39-41, 43, 179, 198 KNM-ER 1813, 19, 35, 40, 44, 45, 47, 81, 179, 198, 199 KNM-ER 2598, 42 KNM-ER 3732, 19, 41 KNM-ER 3733, 42, 46, 179 KNM-ER 3734, 33, 124 KNM-ER 3735, 20, 21, 41, 67, 200 KNM-ER 3891, 34 West Turkana KNM-WT 15000, 39, 42, 44, 67-71, 81, 93, 95, 101-117, 124, 179, 200, 201 KNM-WT 17000, 136, 165, 167, 179 KNM-WT 40000, 36, 179 KNM-WT 42718, 35, 179
The Pulsed Climate Variability Hypothesis
In summary, new paleoclimate data suggest that the long-term drying trend in East Africa was punctuated by episodes Fig. 13.3 Three theoretical models of lake changes in East Africa during the Plio-Pleistocene. Model 1 'smooth' and relatively slow transitions from deep to no lake conditions, which would imply that either high energy wet conditions or prolonged aridity may have influenced human evolution. Model 2 'threshold' rapid transitions from deep to no lake conditions, which would imply...
Contributors
Center for Human Evolutionary Studies, Department of Anthropology, Rutgers University, The State University of New Jersey, 131 George Street, New Brunswick, NJ 08901-1414, USA Department of Anthropology, University of Georgia, Athens, GA 30602, USA renebobe uga.edu Department of Biology, University of Utah, Salt Lake City, UT 84112, USA Bramble bioscience.utah.edu Department of Cell and Developmental Biology, University College London, Anatomy Building, Gower Street, London WC1E 6BT, UK...
New Evidence about the Relationships of Potential Homo Species
The pre-1999 phylogenetic analyses that had tested the hypothesis of Homo monophyly Chamberlain, 1987 Chamberlain and Wood, 1987 Wood, 1991, 1992 Lieberman et al., 1996 Strait et al., 1997 were reviewed in Wood and Collard 1999 . Three phylogenetic analyses carried out since 1999, Curnoe, 2001 Cameron and Groves, 2004 Strait and Grine, 2004 are relevant to the ongoing debate about the phylogenetic relationships of potential early Homo taxa. Curnoe 2001 focused on the phylogenetic relationships...
References Bpr
Ahern, J.C.M., 1998. Underestimating intraspecific variation the problem with excluding Sts 19 from Australopithecus africanus. American Journal of Physical Anthropology 105, 461-480. Aiello, L.C., Collard, M., Thackeray, J.F., Wood, B.A., 2000. Assessing exact randomization-based methods for determining the taxonomic significance of variability in the human fossil record. South African Journal of Science 96, 179-183. Albarede, F., Balter, F. Braga, J. Blichert-Toft, J. Telouk, P., Thackeray,...
Hominin Fossil Sites
This study focuses on three fossiliferous sedimentary accumulations in the Turkana Basin Shungura Formation, Omo Valley, Ethiopia Koobi Fora Formation, East Turkana, Kenya and Nachukui Formation, West Turkana, Kenya , as well as the Hadar Formation Ethiopia , Olduvai Gorge Tanzania , and cave deposits in South Africa Makapansgat, Sterkfontein and Swartkrans . Areas along the Rift Valley in East Africa were chosen because the fossil assemblages and Plio-Pleistocene strata of each of these sites...
Clavicle 1
The clavicles from Nariokotome and Dmanisi all display the typical S-shape curvature seen in modern humans and African apes. Walker and Leakey 1993 describe the acromial ends of Nariokotome clavicles as flattened superiorly and somewhat concave inferiorly. Moving medially, the body of the bone twists by about 30 and becomes more rounded in contour. The sternal end is ovoid, and on the inferior surface there is a low, blunt conoid tubercle approximately one quarter of the way from the lateral...
Sts Sterkfontein Member South Africa ca Ma
This specimen is a well preserved cranial base found in a rubble dump associated with early twentieth century lime-mining activities at Sterkfontein Member 4 . Broom et al. 1950 were impressed with its humanlike morphology, and, later, Clarke 1977 considered whether it should be attributed to Homo sp. rather than A. africanus based on a suite of temporal and sphenoid bone characters. This possibility was reviewed but rejected by Dean and Wood 1982 in favor of a wide range of variation for A....
Why Did Endurance Running Capabilities Evolve
Given the above evidence that ER capabilities are derived in the genus Homo, and that they were probably present to some extent in H. erectus, the final question to address is why these capabilities evolved in the first place. Answering this question, however, is a challenge because it is obvious that humans today - including contemporary hunter-gatherers -no longer need to practice ER although it remains a potentially useful component of some hunter-gatherer subsistence strategies . Thus,...
Clavicle
Although there are a number of fossil clavicular specimens known for early hominins Table 7.1 , most are only small segments and attempts to interpret them have been limited. The most complete specimen missing only a portion of its sternal end is A.L. 333x-6 9 Lovejoy et al., 1982 attributed to A. afarensis. On the basis of the orientation of its lateral end on frontal view and the position of the deltoid attachment area, Ohman 1986 concludes that A.L. 333x-6 9 is distinct from extant...
Defining the Genus Category
Genus definitions use four criteria, two lines of evidence phenotypic and genetic and fall into two categories. The four criteria are the relationships among taxa, information about their adaptive grade, estimates of the genetic distance that separates them, and the estimated time of divergence. At least one researcher Dubois, 1988 has suggested that a fifth criterion, evidence of hybridization between species, should be the primary criterion for grouping species into genera. However, even if...
Medial Epicondyle Fusion Age
Like many other primates, humans ossify the appendicular skeletal joints in sequence from elbow, hip, ankle, knee, wrist, to shoulder Schultz, 1956 , although great apes and humans delay the start of this fusion sequence until puberty or after Figure 9.2 in Smith, 1993 . We can place Nariokotome firmly past puberty and into adolescence by evidence that the process of elbow joint ossification had begun Fig. 10.3 , uniting some of the four elements of the distal humerus epiphysis, and by evidence...
Human Variation in Interlimb Proportions
The humerofemoral index defined above is highly correlated with another interlimb metric, the intermembral index 100 x humerus radius femur tibia . Figure 9.1 is a bivariate plot of these two indices in a human skeletal sample of 314 individuals drawn from a diversity of ethnicities, climates and body sizes African Pygmies, Andaman Islanders, Khoesan, Zulu, African Americans, Sami and Inuit. The parametric and rank order correlations are highly significant p lt 0.001 and similar in magnitude at...
Claviculohumeral Ratio
Because the KNM-WT15000 skeleton includes all of the pectoral girdle shoulder elements, it is possible to further explore this region to try and determine how a shoulder with such limited humeral torsion could have functioned. The claviculohumeral ratio is a commonly used measure of relative clavicular length e.g., Schultz, 1930, 1937 McCown and Keith, 1939 Martin and Saller, 1959 Marquer, 1972 . The estimated total length of 319 mm for the KNM-WT 15000 humerus reported by Walker and Leakey...
Lacruz 2008 Journal Of Anatomy 213 148-158
Aiello, L.C., Key, C., 2002. The energetic costs of being a Homo erectus female. American Journal of Human Biology 14, 551-565. Agossou-Voyeme, A.K., Fachehoun, C.R., Boco, V., Hounnou, G.M., Biaou, O., 2005. Osseous age of the black children of Benin. A population study of 600 children aged from 9 years to 18 years and living in Cotonou. Morphologie 89 285 , 64-70. Allbrook, D., 1961. The estimation of stature in British and East African males. Journal of Forensic Medicine 8, 15-28. Allman,...
Endurance Running and Scavenging
The debate about scavenging in human evolution is long and contentious, largely because it is difficult to prove that the animal bones found in early archaeological sites were procured by scavenging or hunting for reviews, see Bunn, 2001 Dominguez-Rodrigo, 2002 . Another point of contention has been the challenge of evaluating how reliably or effectively early Homo would have been able to scavenge in various habitats. Regardless of the extent to which scavenging occurred, the most likely source...
Pectoral GirdleShoulder Configuration in Early H erectus
The shoulder region of the early H. erectus presents an unexpected combination of features, including relatively short clavicles and very low humeral torsion, but with a fairly modern looking scapula whose glenoid did not face cranially sitting on a barrel-shaped rib cage judging from the shape of the ribs of KNM-WT 15000 Jellema et al., 1993 . Although relative clavicular length is currently unknown for early hominins, if the isometric scaling relationship portrayed in Fig. 7.3 does represent...
References Hif
Acosta, L. Jr, Roy, R.R., 1987. Fiber-type composition of selected hindlimb muscles of a primate cynomolgus monkey . Anatomical Record 218, 136-141. Aiello, L., Dean, M.C., 1990. An Introduction to Human Evolutionary Anatomy. Academic, London. Aiello, L., Wheeler, P., 1995. The expensive tissue hypothesis the brain and digestive system in human and primate evolution. Current Anthropology 36, 199-221. Alexander, R.M., 1991. Elastic mechanisms in primate locomotion. Zeitschrift fur Morphologie...