scholarly journals Tertiary dentine frequencies in extant great apes and fossil hominins

2018 ◽  
Author(s):  
Ian Towle
Keyword(s):  
South African ◽  
Great Apes ◽  
Gorilla Gorilla ◽  
Great Ape ◽  
Loss Of Function ◽  
Gorilla Gorilla Gorilla ◽  
Australopithecus Africanus ◽  
Occlusal Wear ◽  
Fossil Hominins ◽  
Fossil Hominin

Tertiary dentine forms when an odontoblast is directly affected by stimuli, commonly through occlusal wear. In this study the presence of tertiary dentine is recorded in three South African fossil hominin species (Australopithecus africanus, Homo naledi and Paranthropus robustus), and two extant great ape species (Gorilla gorilla gorilla and Pan troglodytes). Frequencies of tertiary dentine were calculated for each species based on macroscopic observations of teeth with dentine exposed through occlusal wear. Overall, the three hominin species have similar tertiary dentine frequencies ranging from 12% to 16.13%. In contrast, over 90% of gorilla teeth with dentine visible show tertiary dentine. Chimpanzees fall between these extremes with 47.21% of teeth affected. Species variances are not related to differences in occlusal wear. Instead, some species appear predisposed to produce tertiary dentine earlier and/or faster than other species. Therefore, tertiary dentine formation has the potential to provide useful information on fossil specimens. For example, the uniformly low rate of tertiary dentine formation in hominins may be due to thick enamel having a similar role in preventing loss of function of teeth, i.e., extending the life of a tooth. In contrast tertiary dentine is clearly an important mechanism for normal dental function in gorillas, and may have evolved to maintain sheering surfaces for masticating tough vegetation.

scholarly journals Tertiary dentine frequencies in extant great apes and fossil hominins

2018 ◽  
Author(s):  
Ian Towle
Keyword(s):  
South African ◽  
Great Apes ◽  
Gorilla Gorilla ◽  
Great Ape ◽  
Loss Of Function ◽  
Gorilla Gorilla Gorilla ◽  
Australopithecus Africanus ◽  
Occlusal Wear ◽  
Fossil Hominins ◽  
Fossil Hominin

Tertiary dentine forms when an odontoblast is directly affected by stimuli, commonly through occlusal wear. In this study the presence of tertiary dentine is recorded in three South African fossil hominin species (Australopithecus africanus, Homo naledi and Paranthropus robustus), and two extant great ape species (Gorilla gorilla gorilla and Pan troglodytes). Frequencies of tertiary dentine were calculated for each species based on macroscopic observations of teeth with dentine exposed through occlusal wear. Overall, the three hominin species have similar tertiary dentine frequencies ranging from 12% to 16.13%. In contrast, over 90% of gorilla teeth with dentine visible show tertiary dentine. Chimpanzees fall between these extremes with 47.21% of teeth affected. Species variances are not related to differences in occlusal wear. Instead, some species appear predisposed to produce tertiary dentine earlier and/or faster than other species. Therefore, tertiary dentine formation has the potential to provide useful information on fossil specimens. For example, the uniformly low rate of tertiary dentine formation in hominins may be due to thick enamel having a similar role in preventing loss of function of teeth, i.e., extending the life of a tooth. In contrast tertiary dentine is clearly an important mechanism for normal dental function in gorillas, and may have evolved to maintain sheering surfaces for masticating tough vegetation.

scholarly journals Dental caries in human evolution: frequency of carious lesions in South African fossil hominins

2019 ◽  
Author(s):  
Ian Towle ◽  
Joel D. Irish ◽  
Isabelle De Groote ◽  
Christianne Fernée
Keyword(s):  
South African ◽  
Human Evolution ◽  
Deciduous Teeth ◽  
Posterior Teeth ◽  
Australopithecus Africanus ◽  
Early Homo ◽  
Carious Lesions ◽  
Fossil Hominins ◽  
Specialized Diet ◽  
Fossil Hominin

AbstractCaries frequencies in South African fossil hominins were observed and compared with other hominin samples. Species studied includeParanthropus robustus,Homo naledi,Australopithecus africanus,early HomoandA. sediba. Teeth were viewed macroscopically with Micro-CT scans used to confirm lesions. Position and severity of each lesion were also noted and described. For all South African fossil hominin specimens studied, 16 have carious lesions, six of which are described for the first time in this study. These are from a minimum of six individuals, and include fourP. robustus,oneH. naledi,and oneearly Homoindividual. No carious lesions were found on deciduous teeth, or any teeth assigned toA. africanus. Most are located interproximal, and only posterior teeth are affected. Caries frequency typically ranges between 1-5% of teeth in non-agricultural human samples, and this pattern seemingly holds true for at least the past two million years in the hominin lineage. Non-agricultural populations significantly above or below this threshold generally have a specialized diet, supporting other dietary evidence thatA. africanuslikely consumed large amounts of tough, non-cariogenic vegetation. Given the common occurrence of caries in the other hominin species, cariogenic bacteria and foods were evidently common in their collective oral environment. Along with recent research highlighting additional examples of caries inH. neanderthalensis, earlyHomoand PleistoceneH. sapiens, caries is clearly an ancient disease that was much more common than once maintained throughout the course of human evolution.

scholarly journals Root grooves on two adjacent anterior teeth of Australopithecus africanus

2017 ◽  
Author(s):  
Ian Towle ◽  
Joel D. Irish ◽  
Marina Elliott ◽  
Isabelle De Groote
Keyword(s):  
South African ◽  
Root Surface ◽  
Dental Erosion ◽  
Tissue Loss ◽  
Cervical Lesions ◽  
Dental Tissue ◽  
Australopithecus Africanus ◽  
Food Items ◽  
Anterior Teeth ◽  
Fossil Hominin

AbstractTooth root grooves and other ante-mortem dental tissue loss not associated with caries found on or near the cementoenamel junction (CEJ) are commonly termed non-carious cervical lesions. Three main processes are implicated in forming these lesions: abrasion, dental erosion, and abfraction. As yet, these lesions have not been described in non-Homo hominins. In this study South African fossil hominin collections were examined for evidence of any type of non-carious cervical lesion. Only one individual shows ante-mortem root grooves consistent with non-carious cervical lesions. Two teeth, a mandibular right permanent lateral incisor (STW 270) and canine (STW 213), belonging to the same Australopithecus africanus individual, show clear ante-mortem grooves on the labial root surface. These lesions start below the CEJ, extend over a third of the way toward the apex, and taper to a point towards the lingual side. Microscopic examination revealed no clear directional striations. The shape of these grooves is extremely similar to clinical examples of dental erosion, with the lack of striations supporting this diagnosis. These are the oldest hominin examples of non-carious cervical lesions and first described in a genus other than Homo; further, the lesions suggest that this individual regularly consumed or processed acidic food items.

Metacarpals and manual phalanges

2020 ◽  
pp. 106-143
Author(s):  
Tracy L. Kivell ◽  
Kelly R. Ostrofsky ◽  
Brian G. Richmond ◽  
Michelle S.M. Drapeau
Keyword(s):  
Body Size ◽  
South African ◽  
Index Finger ◽  
External Morphology ◽  
Australopithecus Africanus ◽  
Fossil Evidence ◽  
Frequent Use ◽  
Selection For ◽  
Locomotor Behaviors ◽  
Fossil Hominin

This chapter presents description and analysis of the metacarpals and manual phalanges from Sterkfontein. Although the morphology is generally similar across the sample where there are duplicates of the same element, there are differences in size that are quite remarkable within the context of all South African hominins. Some very large specimens suggest the presence of individuals at Sterkfontein with much larger hands, and presumably larger body size, at Sterkfontein than those of A. sediba MH2, H. naledi and the Swartkrans hominins. Australopithecus africanus had human-like proportions, but this may be plesiomorphic within the hominoid clade. The potentially less mobile trapezium-Mc1 joint, absence of a fully developed palmar pulp on the distal thumb, more limited pronation of the index finger, and potentially more wedge-shaped trapezoid inferred from the preserved external morphology, is consistent with lower manipulative loading of the thumb than is typical of later Homo. As for other forelimb elements, moderately curved manual phalanges suggests a greater reliance on forelimb-dominated locomotor behaviors and perhaps selection for more frequent use of an arboreal environment in A. africanus than is found in A. afarensis. Thus, within this broader context, the Sterkfontein fossil hominin remains are not unusual. The Sterkfontein hand fossils suggest an overall manipulative and locomotor loading regime that was more similar to that of other South African australopiths and distinct from that of later Homo, but more refined functional interpretations require additional fossil evidence, particularly from associated hand skeletons

scholarly journals A hominin first rib discovered at the Sterkfontein Caves, South Africa

2016 ◽  
Vol Volume 112 (Number 5/6) ◽  
Author(s):  
Gaokgatlhee Tawan ◽  
Daniel García-Martínez ◽  
Jennifer Eyre ◽  
Markus Bastir ◽  
Lee Berger ◽  
...  
Keyword(s):  
South Africa ◽  
South African ◽  
Fossil Record ◽  
Three Dimensional ◽  
Great Apes ◽  
Small Individual ◽  
Geometric Morphometric ◽  
First Rib ◽  
Morphometric Analyses ◽  
Fossil Hominin

Abstract First ribs – the first or most superior ribs in the thorax – are rare in the hominin fossil record, and when found, have the potential to provide information regarding the upper thorax shape of extinct hominins. Here, we describe a partial first rib from Member 4 of the Sterkfontein Caves, South Africa. The rib shaft is broken away, so only the head and neck are preserved. The rib is small, falling closest to small-bodied Australopithecus first ribs (AL 288-1 and MH1). Given that it was recovered near the StW 318 femur excavation, which also represents a small individual, we suggest that the two may be associated. Three-dimensional geometric morphometric analyses were used to quantify the rib fragment morphology and compare it to extant hominoid and other fossil hominin ribs. While only the proximal end is preserved, our analyses show that South African Australopithecus share derived features of the proximal first rib more closely resembling A. afarensis and later hominins than great apes.

scholarly journals High chimpanzee and gorilla densities in a non-protected area on the northern periphery of the Dja Faunal Reserve, Cameroon

Oryx ◽  
2004 ◽  
Vol 38 (2) ◽  
pp. 209-216 ◽  
Author(s):  
J. Dupain ◽  
P. Guislain ◽  
G. M. Nguenang ◽  
K. De Vleeschouwer ◽  
L. Van Elsacker
Keyword(s):  
Protected Areas ◽  
Protected Area ◽  
Gorilla Gorilla ◽  
Great Ape ◽  
Vegetation Types ◽  
Conservation Action ◽  
Gorilla Gorilla Gorilla ◽  
Pan Troglodytes Troglodytes ◽  
Degree Of Isolation ◽  
Effective Conservation

Information on the densities of threatened species in non-protected areas is crucial for assessing the degree of isolation of adjacent protected areas and consequently their potential for preserving species from extinction. Relatively few studies, however, provide such information. We present the results of a survey of the densities of two great ape species, the gorilla Gorilla gorilla gorilla and chimpanzee Pan troglodytes troglodytes, in a non-protected area on the northern periphery of Dja Faunal Reserve, Cameroon. Densities of chimpanzees and gorillas were estimated to be 1.1 and 3.8 weaned individuals per km2, respectively. The results confirm that gorillas prefer building nests in vegetation types with limited visibility, and that within preferred vegetation types for nesting, gorillas select patches that are the most difficult to penetrate, resulting in less conspicuous nests. Although the opposite tendencies were exhibited by chimpanzees, no firm conclusions could be drawn from our data. Despite its non-protected status and past and ongoing logging activities in the area, the densities of gorillas and chimpanzees on the northern periphery of Dja Faunal Reserve are comparable to those found within the reserve itself, indicating the need for developing alternative conservation action to protect these important populations. The creation of a Communal Wildlife Zone in this area is legislatively possible, and could be an effective conservation tool because it has to originate from the local people.

scholarly journals Stable isotopes in fossil hominin tooth enamel suggest a fundamental dietary shift in the Pliocene

2010 ◽  
Vol 365 (1556) ◽  
pp. 3389-3396 ◽  
Author(s):  
Julia A. Lee-Thorp ◽  
Matt Sponheimer ◽  
Benjamin H. Passey ◽  
Darryl J. de Ruiter ◽  
Thure E. Cerling
Keyword(s):  
South African ◽  
Tooth Enamel ◽  
Dietary Shift ◽  
Australopithecus Africanus ◽  
Isotopic Evidence ◽  
High Resolution Analysis ◽  
Resolution Analysis ◽  
Dietary Ecology ◽  
Dietary Shifts ◽  
Fossil Hominin

Accumulating isotopic evidence from fossil hominin tooth enamel has provided unexpected insights into early hominin dietary ecology. Among the South African australopiths, these data demonstrate significant contributions to the diet of carbon originally fixed by C 4 photosynthesis, consisting of C 4 tropical/savannah grasses and certain sedges, and/or animals eating C 4 foods. Moreover, high-resolution analysis of tooth enamel reveals strong intra-tooth variability in many cases, suggesting seasonal-scale dietary shifts. This pattern is quite unlike that seen in any great apes, even ‘savannah’ chimpanzees. The overall proportions of C 4 input persisted for well over a million years, even while environments shifted from relatively closed ( ca 3 Ma) to open conditions after ca 1.8 Ma. Data from East Africa suggest a more extreme scenario, where results for Paranthropus boisei indicate a diet dominated (approx. 80%) by C 4 plants, in spite of indications from their powerful ‘nutcracker’ morphology for diets of hard objects. We argue that such evidence for engagement with C 4 food resources may mark a fundamental transition in the evolution of hominin lineages, and that the pattern had antecedents prior to the emergence of Australopithecus africanus . Since new isotopic evidence from Aramis suggests that it was not present in Ardipithecus ramidus at 4.4 Ma, we suggest that the origins lie in the period between 3 and 4 Myr ago.

scholarly journals Dental caries in South African fossil hominins

2021 ◽  
Vol 117 (3/4) ◽  
Author(s):  
Ian Towle ◽  
Joel D. Irish ◽  
Isabelle De Groote ◽  
Christianne Fernée ◽  
Carolina Loch
Keyword(s):  
South African ◽  
Published Data ◽  
Caries Prevalence ◽  
Posterior Teeth ◽  
Early Homo ◽  
Oral Environment ◽  
Fossil Hominins ◽  
Fossil Hominin ◽  
First Time ◽  
Carious Teeth

Once considered rare in fossil hominins, caries has recently been reported in several hominin species, requiring a new assessment of this condition during human evolution. Caries prevalence and location on the teeth of South African fossil hominins were observed and compared with published data from other hominin samples. Teeth were viewed macroscopically, with lesion position and severity noted and described. For all South African fossil hominin specimens studied to date, a total of 10 carious teeth (14 lesions), including 4 described for the first time here, have been observed. These carious teeth were found in a minimum of seven individuals, including five Paranthropus robustus, one early Homo, and one Homo naledi. All 14 lesions affected posterior teeth. The results suggest cariogenic biofilms and foods may have been present in the oral environment of a wide variety of hominins. Caries prevalence in studied fossil hominins is similar to those in pre-agricultural human groups, in which 1–5% of teeth are typically affected.

scholarly journals Incremental distribution of strontium and zinc in great ape and fossil hominin cementum using synchrotron X-ray fluorescence mapping

2018 ◽  
Vol 15 (138) ◽  
pp. 20170626 ◽  
Author(s):  
Christopher Dean ◽  
Adeline Le Cabec ◽  
Kathryn Spiers ◽  
Yi Zhang ◽  
Jan Garrevoet
Keyword(s):  
Alveolar Bone ◽  
Great Apes ◽  
Great Ape ◽  
Koobi Fora ◽  
X Ray ◽  
Mineralized Tissues ◽  
Calcium Phosphorus ◽  
Acid Solubility ◽  
Fossil Hominin ◽  
Acellular Cementum

Cementum and the incremental markings it contains have been widely studied as a means of ageing animals and retrieving information about diet and nutrition. The distribution of trace elements in great ape and fossil hominin cementum has not been studied previously. Synchrotron X-ray fluorescence (SXRF) enables rapid scanning of large tissue areas with high resolution of elemental distributions. First, we used SXRF to map calcium, phosphorus, strontium and zinc distributions in great ape dentine and cementum. At higher resolution, we compared zinc and strontium distributions in cellular and acellular cementum in regions where clear incremental markings were expressed. We then mapped trace element distributions in fossil hominin dentine and cementum from the 1.55–1.65 million year old site of Koobi Fora, Kenya. Zinc, in particular, is a precise marker of cementum increments in great apes, and is retained in fossil hominin cementum, but does not correspond well with the more diffuse fluctuations observed in strontium distribution. Cementum is unusual among mineralized tissues in retaining so much zinc. This is known to reduce the acid solubility of hydroxyapatite and so may confer resistance to resorption by osteoclasts in the dynamic remodelling environment of the periodontal ligament and alveolar bone.

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