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1.
A relatively complete skeleton of the fossil papionin, Theropithecus brumpti, from the site of Lomekwi, west of Lake Turkana, Kenya, is here described. The specimen, KNM-WT 39368, was recovered at the site of LO 5 (3 degrees 51'N and 35 degrees 45'E), from sediments dated to approximately 3.3Ma. The skeleton is that of an old adult male and preserves a number of articulated elements, including most of the forelimbs and tail. The cranial morphology is that of a large, early T. brumpti, exhibiting a deep mandible with a deeply excavated mandibular corpus fossa, and mandibular alveoli and cheek teeth arrayed in a reversed Curve of Spee. The forelimb skeleton exhibits a unique mixture of characteristics generally associated with a terrestrial locomotor habitus, such as a narrow scapula and a highly stable elbow joint, combined with those more representative of habitual arborealists, such as muscle attachments reflecting a large rotator cuff musculature and a flexible shoulder joint. The forelimb of KNM-WT 39368 also presents several features, unique toTheropithecus, which represent adaptations for manual grasping and fine manipulation. These features include a large, retroflexed medial humeral epicondyle (to which large pronator, and carpal and digital flexor muscles attached) and proportions of the digital rays that denote capabilities for precise opposition between the thumb and index finger. Taken together, these features indicate that one of the earliest recognized representatives of Theropithecus exhibited the food harvesting and processing anatomy that distinguished the genus through time and that contributed to its success throughout the later Pliocene and Pleistocene. Based on the anatomy of KNM-WT 39368 and the known habitat preference of T. brumpti, the species is reconstructed as being a generally terrestrial but highly dexterous, very large-bodied, sexually dimorphic, and possibly folivorous papionin. T. brumpti was adapted for propulsive quadrupedal locomotion over generally even ground, and yet was highly adept at manual foraging. The estimate of 43.8kg body mass for KNM-WT 39368 renders unlikely the possibility that the species, or at least adult males of the species, were highly arboreal. T. brumpti, as represented by KNM-WT 39368, is seen as a large, colorfully decorated, and basically terrestrial papionin that was restricted to riverine forest habitats in the Lake Turkana Basin from the middle to latest Pliocene. 相似文献
2.
Here we describe a complete skull and partial skeleton of a large cercopithecoid monkey (KNM-TH 46700) discovered in the Chemeron Formation of the Tugen Hills at BPRP Site #152 (2.63 Ma). Associated with the skeleton was a mandible of an infant cercopithecoid (KNM-TH 48364), also described here. KNM-TH 46700 represents an aged adult female of Theropithecus brumpti, a successful Pliocene papionin taxon better known from the Omo Shungura Formation in Ethiopia and sites east and west of Lake Turkana, Kenya. While the morphology of male T. brumpti is well-documented, including a partial skeleton with both cranial and postcranial material, the female T. brumpti morphotype is not well-known. This skeleton represents some of the first associated evidence of cranial and postcranial female T. brumpti remains. In addition to the complete skull, postcranial material includes elements of the axial skeleton and lower limb. While aspects of the skeleton conform to those of specimens previously assigned to T. brumpti, other features on the femur and tibia appear to differ from those previously described for this species. It is unclear whether these differences represent general variation within the T. brumpti population, variation between the sexes in T. brumpti, or the incorrect assignment of previous isolated hindlimb specimens. In total, the observable morphological features of the hindlimb suggest that KNM-TH 46700 was a terrestrial quadruped similar to modern savannah baboons (Papio). From the available evidence, it is difficult to assess whether or not KNM-TH 46700 frequently engaged in the specialized squatting and shuffling behavior observed in extant geladas (Theropithecus gelada). 相似文献
3.
Comparison of the skulls of Papio baringensis Leakey 1969 from the Chemeron Formation and P. quadratirostris Iwamoto 1982 from the Usno Formation with those of Theropithecus gelada, T. brumpti, T. darti, T. oswaldi, and several species of Papio indicate that the species from Chemeron and Usno exhibit all, or most, respectively, of the shared derived characters of Theropithecus. We propose that they be removed from Papio and placed in Theropithecus as T. baringensis and T. quadratirostris. Comparison of the specimens of T. baringensis and T. quadratirostris with those of T. brumpti indicate that the former two species have some of the derived characters of T. brumpti but are primitive in others. We propose that the three species form the following phyletic lineage: T. baringensis-T. quadratirostris-T. brumpti. With these referrals, there are now six species of the genus Theropithecus. Based on geologic grounds, the specimens from Chemeron are about 4.0 million years (m.y.), that from Usno between 3.3 and 3.4 m.y., and those of T. brumpti between 2.0 and 2.8 m.y. in age. We also show that the most complete specimen of Papio sp. nov. from Olduval Gorge belongs to T. oswaldi. With the removal of these specimens from Papio, the East African fossil record of this genus, apart from isolated teeth, comprises only 21 specimens, while that of Theropithecus comprises at least 300 specimens. 相似文献
4.
5.
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. 相似文献
6.
This study conducts a phylogenetic analysis of extant African papionin craniodental morphology, including both quantitative and qualitative characters. We use two different methods to control for allometry: the previously described narrow allometric coding method, and the general allometric coding method, introduced herein. The results of this study strongly suggest that African papionin phylogeny based on molecular systematics, and that based on morphology, are congruent and support a Cercocebus/Mandrillus clade as well as a Papio/Lophocebus/Theropithecus clade. In contrast to previous claims regarding papionin and, more broadly, primate craniodental data, this study finds that such data are a source of valuable phylogenetic information and removes the basis for considering hard tissue anatomy “unreliable” in phylogeny reconstruction. Among highly sexually dimorphic primates such as papionins, male morphologies appear to be particularly good sources of phylogenetic information. In addition, we argue that the male and female morphotypes should be analyzed separately and then added together in a concatenated matrix in future studies of sexually dimorphic taxa. Character transformation analyses identify a series of synapomorphies uniting the various papionin clades that, given a sufficient sample size, should potentially be useful in future morphological analyses, especially those involving fossil taxa. 相似文献
7.
The several known archeological occurrences from the Shungura Formation (Members E and F) are discussed within the context of their particular depositional and paleoenvironmental settings, and the broader context of the Pliocene of the Turkana Basin. These assemblages date from 2·3–2·4 Ma, and are among the oldest yet known in Africa. In situ archeological assemblages are restricted to the distal edge of fluviatile levees, behind gallery forests and at the edge of open savanna. Extensive and rather dense scatters of slightly disturbed quartz artifacts are linked to large expanses of braided stream situations. Lag components are derived from stream beds. There is no available evidence of occupation either under riverine or deltaic forest settings or on dryland. Hominid skeletal remains from this interval, none of which occur at or are directly associated with such archeological occurrences, are attributed to two hominid taxa. Most specimens represent a “robust” australopithecine and are attributed here to A. aethiopicus. A few hominid teeth are attributed to aff. Homo sp. 相似文献
8.
Fred Spoor Meave G. Leakey Louise N. Leakey 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1556):3377-3388
The 3.5-Myr-old hominin cranium KNM-WT 40000 from Lomekwi, west of Lake Turkana, has been assigned to a new hominin genus and species, Kenyanthropus platyops, on the basis of a unique combination of derived facial and primitive neurocranial features. Central to the diagnosis of K. platyops is the morphology of the maxilla, characterized by a flat and relatively orthognathic subnasal region, anteriorly placed zygomatic processes and small molars. To study this morphology in more detail, we compare the maxillae of African Plio-Pleistocene hominin fossils and samples of modern humans, chimpanzees and gorillas, using conventional and geometric morphometric methods. Computed tomography scans and detailed preparation of the KNM-WT 40000 maxilla enable comprehensive assessment of post-mortem changes, so that landmark data characterizing the morphology can be corrected for distortion. Based on a substantially larger comparative sample than previously available, the results of statistical analyses show that KNM-WT 40000 is indeed significantly different from and falls outside the known range of variation of species of Australopithecus and Paranthropus, contemporary Australopithecus afarensis in particular. These results support the attribution of KNM-WT 40000 to a separate species and the notion that hominin taxonomic diversity in Africa extends back well into the Middle Pliocene. 相似文献
9.
Escherihica coliumC122::Tn5 cells were γ-radiated (137Cs, 750 Gy, under N2), and lac-constitutive mutants were produced at 36% of the wild-type level (the umC strain was not deficient in spontaneous mutagenesis, and the mutational spectrum determined by sequencing 263 spontaneous lacId mutations was very similar to that for the wild-type strain). The specific nature of the umC strain's partial radiation was determined by sequencing 325 radiation-induced lacId mutations. The yields of radiation-induced mutation classes in the umC strain (as a percentage of the wild-type yield) were: 80% for A · T → G · C transitions, 70% for multi-base additions, 60% for single-base deletions, 53% for A · T → C · G transversions, 36% for G · C → A · T transitions, 25% for multi-base deletions, 21% for A · T → T · A transversions, 11% for G · C → C · G transversions, 9% for G · C → T · A transversions and 0% for multiple mutations. Based on these deficiencies and other factors, it is concluded that the umC strain is near-normal for A · T → G · C transitions, single-base deletions and possibly A · T → C · G transversions; is generally deficient for mutagenesis at G · C sites fro transversions, and is grossly deficient in multiple mutations. Damage at G · C sites seems more difficult for translesion DNA synthesis to bypass than damage at A · T sites, and especially when trying to produced a transversion. The yield of G · C → A · T transitions in the umC strain *36% of the wild-type level) argues that a basic sites are involved in no more than 64% of γ-radiation-induced base substitutions in the wild-type strain. Altogether, these data suggest that the UmuC and UmuD′ proteins facilitate, rather than being absolutely required for, translesion DNA synthesis; with the degree of facilitation being dependent both on the nature of the noncoding DNA damage, i.e., at G · C vs A · T sites, and on the nature of the misincorporated base, i.e., whether it induces transversions or transitions. 相似文献
10.
Hlne Roche Jean-Philip Brugal Anne Delagnes Craig Feibel Sonia Harmand Mzalendo Kibunjia Sandrine Prat Pierre-Jean Texier 《Comptes Rendus Palevol》2003,2(8):663-673
Plio-Pleistocene archaeological sites in the Nachukui Formation, West Turkana, Kenya: synthetic results 1997–2001. Stretched along the western side of the Turkana Basin, the Nachukui Formation preserves a large number of Plio-Pleistocene archaeological sites. Research carried out by the WTAP documents hominid behavioral evolution and technical diversity, through a time period ranging from 2.35 Myr to 0.7 Myr and within a relatively precise chronostratigraphic and paleoenvironmental frame. This work is based on comprehensive excavations conducted between 1997 and 2001 at the Late Pliocene and Early Pleistocene site complexes of the formation. To cite this article: H. Roche et al., C.R. Palevol 2 (2003). 相似文献
11.
Pudu puda is a very small deer that inhabits humid areas of the temperate forests in Chile and Argentina and is one of the less known South American deer. We provide an updated distribution of Pudu puda in Argentina, with georeferenced sighting localities, and some qualitative features of its habitat such as forest type and understory. We also analyse the effects of human settlements, cattle and invasive mammals (Cervus elaphus and Sus scrofa) on the distribution of the southern pudu. We obtained information on Pudu puda occurrence from unpublished sources including protected areas provided by National Parks Administration and interviews of local residents. In the north sector of Nahuel Huapi National Park, where high density of records was found, we obtained information about some qualitative habitat features, proximity of Pudu puda sighting localities to human settlements, presence of invasive mammals and cattle. We recorded a total of 54 new localities for Pudu puda in Argentina, the northernmost record at S 39°23′, W 71°17′ and the southernmost at S 42°58′, W 72°00′. We recorded low frequency of human settlements, Sus scrofa and Cervus elaphus in Pudu puda sighting localities. We did not detect exclusion of Pudu puda from areas with cattle occurrence. Sighting localities of southern pudu were made mostly in monotypic mature Nothofagus dombeyi forest, with dense understory dominated by Chusquea coleu. 相似文献
12.
13.
Hadar is well known as one of the most productive early hominin sites in the world. Between 1972 and 1994 a large sample of fossil cercopithecid specimens was collected from Hadar and the nearby sites of Geraru, Ahmado, and Leadu. At least five, and possibly six, species are present in the sample, including two chronological subspecies of Theropithecus oswaldi. T. o. cf. darti is known from the Middle Pliocene deposits in the Hadar area, along with Parapapio cf. jonesi, cf. Rhinocolobus turkanaensis, and a new species of Cercopithecoides, C. meaveae. There are also isolated molars from the Middle Pliocene of a large colobine which most likely represent cf. R. turkanaensis, but may also represent another large colobine known from the nearby site of Maka in the Middle Awash. T. o. oswaldi is represented from younger deposits of Late Pliocene and Early Pleistocene age, along with the large colobine Cercopithecoides kimeui. Throughout the sequence Theropithecus oswaldi is by far the most abundant cercopithecid, with the other taxa being comparatively rare. The Parapapio material from Hadar is important as the only securely identifiable material of the genus in the East African Pliocene. Furthermore, the Hadar material includes the only associated postcranial remains for the genus. If the tentative identification of Rhinocolobus is correct, then the Hadar sample is the only known occurrence outside of the Turkana Basin. Cercopithecoides meaveae is a new species, currently only known from the Hadar region, most importantly by the associated partial skeleton from Leadu. It appears to show adaptations for terrestrial locomotion. Finally, Cercopithecoides kimeui, a very large colobine previously known from Olduvai Gorge, Koobi Fora, and Rawi is recorded from the uppermost part of the Formation. 相似文献
14.
John W. Huffman Simon M. Bushell John R. A. Miller Jenny L. Wiley Billy R. Martin 《Bioorganic & medicinal chemistry》2002,10(12):7809
Three series of new cannabinoids were prepared and their affinities for the CB1 and CB2 cannabinoid recptors were determined. These are the 1-methoxy-3-(1′,1′-dimethylalkyl)-, 1-deoxy-11-hydroxy-3-(1′,1′-dimethylalkyl)- and 11-hydroxy-1-methoxy-3-(1′,1′-dimethylalkyl)-Δ8-tetrahydrocannabinols, which contain alkyl chains from dimethylethyl to dimethylheptyl appended to C-3 of the cannabinoid. All of these compounds have greater affinity for the CB2 receptor than for the CB1 receptor, however only 1-methoxy-3-(1′,1′-dimethylhexyl)-Δ8-THC (JWH-229, 6e) has effectively no affinity for the CB1 receptor (Ki=3134±110 nM) and high affinity for CB2 (Ki=18±2 nM). 相似文献
15.
Comparison of diatom data from modern surface sediments in Prydz Bay and the Kerguelen Plateau with diatom assemblages from the Sørsdal Formation, Vestfold Hills, indicates that the climate was warmer than present during the early Pliocene (4.5–4.1 Ma). Extant, sea-ice associated diatoms are significantly less abundant throughout the Sørsdal Formation than in the modern Antarctic coastal zone. Extant diatoms in the Sørsdal Formation, including Stellarima stellaris, Thalassiosira oliverana, Fragilariopsis sublinearis, Pseudo-nitzschia turgiduloides and Eucampia antarctica var. recta, are consistent with annual sea-surface temperatures (SST) of between −1.8 and 5.0°C. The presence of S. stellaris indicates that the summer SSTs were >3°C during some intervals. The absence of calcareous coccoliths and the silicoflagellate Dictyocha suggests that the upper limit for summer SST was <5°C. These data indicate that early Pliocene summer SST were between 1.6 and 3°C warmer than today. Abundant Chaetoceros cysts infer that stratified, open-water conditions were present during summer/spring. Ice sheet models suggest that warming of the magnitude evident in the Sørsdal Formation (≤3°C) should have resulted initially in increased snow accumulation and ice sheet growth. However, ice sheet growth was probably short-lived, as the long-term response to this warming in the early Pliocene resulted in a significant decrease in ice volume and deposition of the Sørsdal Formation. Other factors, such as increased basal-ice sliding and higher discharge (icebergs and melt-water), probably led to significantly elevated ablation rates from the Pliocene ice sheet, resulting in ice sheet retreat. 相似文献
16.
J. C. Ohman C. Wood B. Wood R. H. Crompton M. M. Günther L. Yu R. Savage W. Wang 《Human Evolution》2002,17(3-4):129-141
The specimen KNM-WT 15000 is an exceptionally complete 1.53 Myr juvenile skeleton of Homo erectus from West Turkana, Kenya.
It therefore provides a unique opportunity to examine stature estimates of fossil hominids based strictly on long bone lengths.
Using recovered axial and appendicular elements of KNM-WT 15000 that contributed to stature during life, we conclude that
KNM-WT 15000 was much shorter at time-of-death than previous estimates that used only appendicular elements. We conservatively
estimate stature-at-death at about 147 cm, although this individual could have been as short as 141 cm. Because long bone
based estimates of stature also imply the axial skeletal proportion, our new stature estimate stems from the recognition of
axial/appendicular disproportion in the individual KNM-WT 15000. It is possible that the peripubescent age-at-death of this
specimen, and any resulting differential maturity between the appendicular and axial skeleton, may have contributed to previous
overestimates of stature-at-death. However, the possibility that this individual was abnormal, as implied by axial/appendicular
disproportion, remains to be fully tested. Regardless, these results suggest that some interpretations of the biology of early
African Homo erectus, largely based upon KNM-WT 15000, should be viewed with caution.
5 Primate Evolution and Morphology Group, Department of Human 相似文献
17.
Smith SL 《American journal of physical anthropology》2004,125(2):105-120
The skeleton of the Homo erectus boy from West Lake Turkana, Kenya (KNM-WT 15000), is remarkably complete, and this individual has thus provided a case study for several researchers examining Homo erectus growth. Using data from a longitudinal study of Montreal French-Canadian children, it is shown that while dental and skeletal ages match reasonably well at the level of a sample of children, individuals can display differences between skeletal and dental ages of 2 years or more. Furthermore, the relationship between these two markers may change over time in individual children. It is also possible to find children with patterns of dental maturation similar to KNM-WT 15000's pattern in the Montreal sample. Therefore, neither the discrepancy between skeletal age and dental age alone nor the pattern of dental maturation as assessed by dental stages precludes a human-like pattern of growth, including an adolescent growth spurt, for this individual. Some indicators (e.g., estimated body size for predicted age, and enamel formation) do suggest possible growth-patterning differences from modern humans, and therefore earlier maturation is a reasonable hypothesis, but caution is warranted, given the large degree of modern human variation in developmental markers and the inherent uncertainty in precise estimation of KNM-WT 15000's maturational parameters. 相似文献
18.
Among several highly fossiliferous localities in the Bloubank Valley (Gauteng, South Africa), the Cooper's Cave System has been known since 1938 and has produced a rich fossil assemblage, including some remains of the early hominin Paranthropus robustus. In 2001, excavations began at a new locality, Cooper's D, which dates to ~1.4-1.5 Ma. Although hominins are relatively rare in the assemblage, remains of cercopithecoid primates are much more common. Craniodental fossils currently indicate the possible presence of at least three large-bodied cercopithecoid primate genera at Cooper's D: Gorgopithecus, Papio, and Theropithecus. In this study, we identify and describe > 100 cercopithecoid primate postcranial fossils representing all regions of the appendicular skeleton. The specimens come from several age classes and size morphs; more than one third of the fossils described are from sub-adult and juvenile individuals. The adult postcranial fossils vary substantially in size, with body masses estimated between 30 and 60 kg (from 16 of the better preserved specimens). The functional morphology of the postcranial remains indicate that these elements come from animals that likely utilized terrestrial substrates, but they remain difficult to definitively attribute to Gorgopithecus, Theropithecus, or Papio given the absence of associated skeletons. The smaller specimens likely belong to Papio while the larger ones can be attributed to the other two genera. Because Cooper's D has also yielded fossils of the early hominin Paranthropus robustus, this raises the question of how these four large-bodied, mostly terrestrial primates sympatrically utilized the landscape. 相似文献
19.
Alan L. Deino Gary R. Scott Mulugeta Alene Yohannes Haile-Selassie 《Journal of human evolution》2010,58(2):111-3331
40Ar/39Ar dating of tuffs and mafic lavas, tephra geochemistry, and paleomagnetic reversal stratigraphy have been used to establish the chronostratigraphy of the Pliocene hominid-bearing fossiliferous succession at Woranso-Mille, a paleontological study area in the western part of the central Afar region of Ethiopia. The succession in the northwestern part of the study area ranges in 40Ar/39Ar age from 3.82-3.570 Ma, encompassed by paleomagnetic subchron C2Ar (4.187-3.596 Ma). One of the major tuff units, locally named the Kilaytoli tuff, is correlative on the basis of age and geochemistry to the Lokochot Tuff of the Turkana Basin. A hominid partial skeleton (KSD-VP-1) was found in strata whose precise stratigraphic position and age is still under investigation, but is believed to correspond to the later part of this interval. Woranso-Mille fills a significant gap in the fossil record of northeastern Africa at the time of the lower to middle Pliocene transition, when many extant species lineages of African fauna were established. 相似文献
20.
Hui Ye Haidong Xu Cigang Yu Yijun Dai Guiyou Liu Wenping Xu Sheng Yuan 《Enzyme and microbial technology》2009,45(4):282-287
Transforming naringin using the mycelium of Trichoderma harzianum CGMCC 1523 produces two metabolites, 3′,4′,5,7-tetrahydroxy flavanone-7-rhamnoglucoside (3′-OHN) and 3′,4′,5′,5,7-pentahydroxy flavanone-7-rhamnoglucoside (3′,5′-DOHN), both of which were characterized by ESI–MS, 1H NMR and 13C NMR analyses. The time course of the biotransformation by T. harzianum showed that 3′-OHN and 3′,5′-DOHN appeared simultaneously at 6 h, and the conversion yield (32.6%) of 3′,5′-DOHN was higher (10.6%) than that of 3′-OHN at 56 h. The optimal biotransformation temperature was 30 °C, the optimal pH was 5.0, and the optimal concentration of naringin was 400 mg/l. The bigger volume of biotransformation mixture and lower shaking speed did not favor hydroxylation reactions. The radical scavenging activity of naringin at 2000 μM was 11.1%, whereas activity of 3′-OHN at 100 μM could reach 38.4%, which is 68.6 times more than naringin. Antioxidative activity of 3′,5′-DOHN was increased 13.5% at 100 μM compared to 3′-OHN. 相似文献