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1.
Soc Sci Med ; 350: 116936, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38728976

RESUMO

Indigenous Peoples are exposed to the impacts of the climatic, ecological and socioeconomic changes, yet there is a need for a better understanding of their health and higher involvement of Indigenous Peoples in health promotion design and implementation. Our study brings empirical data on the healthcare system of the Baka, forager-horticulturalists from Cameroon. Using a mixed methods approach, we explored the health issues they encounter, the emic determinants of health and healthcare system, and the different threats towards their healthcare system. We conducted focus group discussions, interviews with experts, and self-reported health recalls with 302 individuals living in two settlements from southeastern Cameroon during two fieldwork periods between June and November 2022. Our insights highlight the prevalence of respiratory and children's digestive issues, and the occurrence of illnesses implying a combination of symptoms that would deserve further Western biomedical attention. The Baka's healthcare relies on medicinal plants, knowledge experts, and on the social cohesion of the community, all largely affected by the local social-ecological impacts of global change. Exposure to the market and health facilities does not seem to relate to Baka's health state and practices but might affect their perception of health. Deforestation, poor water quality, and alcohol (ab)use were reported and observed threats to the Baka's health and healthcare system. Our work supplies empirical evidence for a better understanding of Baka's health and healthcare system, helpful in designing health prevention and policies adapted to their reality and culture. Further research and interventions on health should consider the current threats to Baka's local ecosystems and cultural knowledge. These insights contribute to a higher recognition of the Baka's, and most broadly, the Indigenous Peoples' emic perspective on health, and on culturally grounded indicators of the resilience of their healthcare system to current and future challenges.


Assuntos
Grupos Focais , Povos Indígenas , Humanos , Camarões , Povos Indígenas/psicologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Pesquisa Qualitativa , Adolescente , Idoso
2.
J Anthropol Sci ; 101: 171-183, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37543984

RESUMO

Many people and organizations misunderstand the concept behind the name Pygmy. This misunderstanding leads them to misinterpretations and erroneous judgements about its use. This article goes back to the origin of the name in order to clarify the meaning that it has today, especially for the Pygmies themselves. The term 'pygmy' originated in ancient Greece where it was employed for a legendary people who, in Greek mythology, were engaged in an unceasing battle against cranes. Although the morphology of the pygmies described by the ancient Greeks cannot be fully characterized, the term 'pygmy' was used for centuries to refer to a population of small stature living close to the Nile. This led scientists and travellers in modern times to refer to populations of small stature living in equatorial Africa as pygmies. The distinction between Pygmies and non-Pygmies in this region matches the presence of two kinds of populations whose identities are defined in contraposition to one another by socio-cultural aspects. Genetic population studies have suggested that the Pygmies split from non-Pygmy populations around 60,000 years BP. Very importantly, the use of the name Pygmy is gratifying to the Pygmies themselves and it appears in the title of almost all Pygmy rights organizations. The name Pygmy thus covers populations sharing a particular phenotype, having a common origin and thus a biological identity, as well as socio-cultural characteristics which are diverse but nevertheless distinguish them from non-Pygmy populations. Furthermore, the name Pygmy has a dual function for the Pygmies themselves, at once asserting their common identity in contraposition to non-Pygmies ("Big-blacks" as they call them) and conveying their claims against those who despise them, who are the same "Big-blacks".

3.
Ann N Y Acad Sci ; 1516(1): 197-211, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35902997

RESUMO

In epithelia, claudin proteins are important components of the tight junctions as they determine the permeability and specificity to ions of the paracellular pathway. Mutations in CLDN10 cause the rare autosomal recessive HELIX syndrome (Hypohidrosis, Electrolyte imbalance, Lacrimal gland dysfunction, Ichthyosis, and Xerostomia), in which patients display severe enamel wear. Here, we assess whether this enamel wear is caused by an innate fragility directly related to claudin-10 deficiency in addition to xerostomia. A third molar collected from a female HELIX patient was analyzed by a combination of microanatomical and physicochemical approaches (i.e., electron microscopy, elemental mapping, Raman microspectroscopy, and synchrotron-based X-ray fluorescence). The enamel morphology, formation time, organization, and microstructure appeared to be within the natural variability. However, we identified accentuated strontium variations within the HELIX enamel, with alternating enrichments and depletions following the direction of the periodical striae of Retzius. These markings were also present in dentin. These data suggest that the enamel wear associated with HELIX may not be related to a disruption of enamel microstructure but rather to xerostomia. However, the occurrence of events of strontium variations within dental tissues might indicate repeated episodes of worsening of the renal dysfunction that may require further investigations.


Assuntos
Amelogênese , Xerostomia , Claudina-3 , Claudina-4 , Claudinas/metabolismo , Eletrólitos , Feminino , Humanos , Estrôncio , Junções Íntimas/metabolismo
4.
PLoS One ; 17(3): e0264761, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35259192

RESUMO

Reproductive seasonality is a phenomenon common to human and animal populations and driven by, among others, climatic variables. Given the currently changing climate and its impacts on both the environment and human lives, the question arises of its potential effects on reproductive seasonality. Few studies have specifically explored the seasonality of reproduction among hunter-gatherers and anyone investigated how current climate change might affect this phenomenon. In this study we addressed reproductive seasonality in the Baka Pygmy living in African rain forests. Since reproductive seasonality can be linked to weather patterns, we explore this possibility. However, climatic variables driving weather patterns have changed over the years, so we assessed whether this has influenced the Baka reproductive pattern. Based on 34 years of written birth records and oral questionnaires from 13 years of systematic fieldwork, we observed a bimodal birth pattern with two birth peaks at 6-month intervals. Our results demonstrate that precipitation at conception or at birth potentially has effects, respectively negative and positive on the monthly number of births; and temperature has a role in controlling other variables that do affect the reproductive pattern. Changing weather patterns appear to be affecting the reproductive seasonality in the Baka, suggesting that attention needs to be given to the influence of global climate change on forager societies.


Assuntos
População Negra , Transtornos do Crescimento , Mudança Climática , Humanos , Reprodução , Estações do Ano , Tempo (Meteorologia)
5.
PLoS One ; 17(2): e0263590, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35143559

RESUMO

Excess fat is a risk factor for many chronic diseases which can lead to premature mortality. Many studies have proposed predictive equations for body fat mass and body fat mass percentage based on anthropometric measures in relation to age and sex. However, the use of these predictive equations on other subject samples may not be relevant. Our objective is to assess whether the predictive equations proposed in the literature are generalizable to any population. We obtained fat mass and fat percentage on a reference population using Absorptiometry DXA. The predictive equations were applied to our population and the mean and individual differences between actual and estimated values were obtained. Predictive equations obtained from a reduced number of subjects have a very high Standard Error of Estimate (>3) and therefore their accuracy is not acceptable. Only the formulae established from a large number of individuals allow the estimation of values whose Standard Error of Estimate is less than 3. These equations, thanks to the large sample size, include a sufficiently large variability in anthropometric measurements covering the diversity of anthropometric values for the same fat value. However, predictive equations based on a large sample size, while exhibiting no current difference in variances, can show a shift in mean values. This mean-shift is the result of differences in DXA devices and needs to be corrected. It means that DXA values from a few individuals in the population under study must be obtained to calculate a corrective factor.


Assuntos
Antropometria , Distribuição da Gordura Corporal/métodos , Absorciometria de Fóton , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Adulto Jovem
6.
Sci Rep ; 11(1): 23087, 2021 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-34845260

RESUMO

Childhood is an ontogenetic stage unique to the modern human life history pattern. It enables the still dependent infants to achieve an extended rapid brain growth, slow somatic maturation, while benefitting from provisioning, transitional feeding, and protection from other group members. This tipping point in the evolution of human ontogeny likely emerged from early Homo. The GAR IVE hemi-mandible (1.8 Ma, Melka Kunture, Ethiopia) represents one of the rarely preserved early Homo infants (~ 3 years at death), recovered in a richly documented Oldowan archaeological context. Yet, based on the sole external inspection of its teeth, GAR IVE was diagnosed with a rare genetic disease-amelogenesis imperfecta (AI)-altering enamel. Since it may have impacted the child's survival, this diagnosis deserves deeper examination. Here, we reassess and refute this diagnosis and all associated interpretations, using an unprecedented multidisciplinary approach combining an in-depth analysis of GAR IVE (synchrotron imaging) and associated fauna. Some of the traits previously considered as diagnostic of AI can be better explained by normal growth or taphonomy, which calls for caution when diagnosing pathologies on fossils. We compare GAR IVE's dental development to other fossil hominins, and discuss the implications for the emergence of childhood in early Homo.


Assuntos
Hominidae/crescimento & desenvolvimento , Mandíbula/crescimento & desenvolvimento , Paleontologia/métodos , Amelogênese Imperfeita , Animais , Arqueologia/métodos , Evolução Biológica , Esmalte Dentário/anatomia & histologia , Etiópia , Feminino , Fósseis , Geografia , Cabeça , Humanos , Pesquisa Interdisciplinar , Mandíbula/anormalidades , Síncrotrons , Dente/crescimento & desenvolvimento
7.
Sci Rep ; 11(1): 16480, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389746

RESUMO

The Baka Pygmies are known for their short stature resulting from a reduced growth rate during infancy. They are peculiar also for their teeth erupt earlier than in any other African population, and their posterior dentition is larger than in non-Pygmy populations. However, the Baka's dental morphology, like several other aspects of their biology, is still understudied. Here, we explore the variation of the Baka's deciduous upper and lower second molars (dm2s) in comparison to a geographically heterogeneous human sample by means of 3D geometric morphometrics and analysis of dental traits. Our results show that the different populations largely overlap based on the shape of their dm2s, especially the lower ones. Their distal region and the height of the dentinal crown differ the most, with the Baka showing the most extreme range of variation. Upper and lower dm2s covary to a great extent (RV = 0.82). The Baka's and South Americans' dm2s were confirmed among the largest in our sample. Despite the Baka's unique growth pattern, long-lasting isolation, and extreme dental variation, it is not possible to distinguish them from other populations based on their dm2s' morphology only.


Assuntos
Variação Anatômica , População Negra , Dente Molar/anatomia & histologia , Dente Decíduo/anatomia & histologia , Feminino , Humanos , Lactente , Masculino
8.
Sci Rep ; 11(1): 4817, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649394

RESUMO

Patterns of human growth established for one population have rarely been tested in other populations. In a previous study, three growth curves from puberty were modelled for each sex in a longitudinal study of a Caucasian population based on stature, age at peak of growth and biological maturation. Each curve represents the canalisation of growth associated with the type of puberty. The high precision (± 3 cm) of individual adult stature predictions shows that growth kinetics are already set up at puberty and are canalised depending on biological maturity. Our aim is to assess whether this model can be extrapolated to other populations to test whether growth canalisation is a population-dependent phenomenon or if the model reflects a canalisation pattern specific to our species. The modelled curves predicted adult stature with the same high degree of precision in basketball players and the Baka pygmies. Therefore, (1) the relationship between growth kinetics and age at maturity is similar in all populations and (2) growth according to pubertal stages follows the same canalisation patterns in the populations despite the wide differences in their average adult statures. It suggests that morphological diversity in modern humans results from processes taking place in early development.


Assuntos
Estatura/fisiologia , Transtornos do Crescimento/epidemiologia , Vigilância da População/métodos , Puberdade/fisiologia , Adolescente , Basquetebol/fisiologia , Criança , Feminino , Humanos , Cinética , Estudos Longitudinais , Masculino
9.
J Hum Evol ; 149: 102896, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33069911

RESUMO

Recent studies have provided great insight into hominin life history evolution by utilizing incremental lines found in dental tissues to reconstruct and compare the growth records of extant and extinct humans versus other ape taxa. Among the hominins, studies that have examined Retzius periodicity (RP) variation have come to contradictory conclusions in some instances. To clarify RP variation among hominins and better place this variation in its broader evolutionary context, we conduct the most comprehensive analysis of published RP values for hominins and great apes to date. We gathered all available data from the literature on RP data from extant humans, great apes, and fossil hominins and assessed their variation using parametric and nonparametric analyses of variance. We also performed phylogenetic generalized least-squares regressions of RP data for these taxa as well as a larger set of hominoids for which RP data have been published against data for body mass, encephalization, and mean semicircular canal radius (a proxy for metabolic rate). Our results show that modern humans have a mean RP significantly differing from that of other hominins. Pongo also is significantly different from nearly all other taxa in all analyses. Our results also demonstrate that RP variation among hominins scales with respect to body mass, encephalization, and semicircular canal radius similarly to other hominids but that modern humans and Pongo stand out in this regard. Operating within the hypothesis that RP reflects autonomic biorhythms that regulate multiple life history variables, our results reinforce the idea that Homo sapiens has evolved a life history distinct from other hominins, even from other members of Homo, and suggest that many of these life history differences may be driven by hypothalamic output from the brain.


Assuntos
Esmalte Dentário/crescimento & desenvolvimento , Hominidae/crescimento & desenvolvimento , Animais , Feminino , Fósseis , Masculino
10.
Am J Phys Anthropol ; 170(4): 622-628, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31599980

RESUMO

OBJECTIVES: Central African small-scale foragers subsist primarily on hunting game activities and wild plant-food gathering. Starch-rich tubers are underground storage organs (USOs) and staple food resources in savanna and tropical rainforests. However, little is known about the effect of USO consumption on tooth wear development in living hunter-gatherers. We report age- and sex-dependent tooth wear rates in forest-dwelling Baka Pygmies with well-documented wild-yam-tuber-based diet to explore the long-term impact of USO mechanical hardness and abrasiveness on the wearing down of the teeth. MATERIALS AND METHODS: Percentages of dentine exposure (PDEs) of permanent left mandibular first molars (M1 ) were recorded using in vivo high-resolution replicas of Baka individuals (aged 8-33 years), inhabiting Le Bosquet district in Cameroon (Western Africa). Regression and covariance analyses were used to test the effect of individual aging by sex on PDE rates. RESULTS: We found a strong increase of PDE by age among Baka individuals. No evidence of sexual dimorphism in wear patterns suggests similar sex-related dietary and masticatory demands during growth. Overall, greatest dentine exposure values ≈4% denote unexpected slow wear down rates for foraging diets relying on USO consumption. DISCUSSION: The low molar wear rates with age found in Baka Pygmies contrast with extensive wear rates in savanna-dwelling foragers, reflecting differences in thermal processing techniques affecting fracture toughness and grittiness of mechanically challenging foods. Our findings reveal that culture-specific dietary proclivities influence tooth wear among foraging behaviors with important implications in hominin dietary versatility and abrasive stress on chewing surfaces.


Assuntos
População Negra/etnologia , Odontometria , Desgaste dos Dentes/patologia , Adolescente , Adulto , Fatores Etários , Antropologia Física , Camarões , Criança , Feminino , Humanos , Masculino , Desgaste dos Dentes/etiologia , Adulto Jovem
11.
Ann Hum Biol ; 46(6): 467-474, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31554436

RESUMO

Background: The relationship between tooth size and stature has been analysed extensively at the interspecies level but has received less attention at the intraspecies level. The relationship between these two parameters does not seem to be the same among modern human populations.Aim: The aim of this study is to analyse the relationship between tooth dimensions and body measurements in the Baka Pygmies.Subjects and methods: Height, weight, and tooth dimensions were obtained for 45 adult Baka females and 17 males from Le Bosquet (Cameroon). Correlations were obtained between the variables and compared to results for other human populations.Results: The Baka population is distinctive in the small number of significant correlations. Only two buccolingual diameters among Baka females show any significant correlation with height. The lack of significant correlations between tooth dimensions and body dimensions among the Baka means that changes in body size are accompanied by random variations in tooth dimensions.Conclusion: The absence of correlations may be accounted for by the impact of environmental effects on the somatic growth of the Baka producing a Pygmy phenotype adapted to live in the forest. It is worth noting that many correlations become significant when sexes are pooled.


Assuntos
Tamanho Corporal , Dente/anatomia & histologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Camarões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Odontometria , Tamanho do Órgão , Adulto Jovem
12.
Rapid Commun Mass Spectrom ; 33(22): 1761-1773, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31287915

RESUMO

RATIONALE: Stable isotopic analyses are increasingly used to study the diets of past and present human populations. Yet, the carbon and nitrogen isotopic data of modern human diets collected so far are biased towards Europe and North America. Here, we address this gap by reporting on the dietary isotopic signatures of six tropical African communities: El Molo, Turkana (Kerio), Luhya (Webuye), Luhya (Port Victoria), and Luo (Port Victoria) from Kenya, and Baka from Cameroon; representing four subsistence strategies: fishing, pastoralism, agriculturalism, and hunter-gatherer. METHODS: We used an elemental analyser coupled in continuous-flow mode to an isotope ratio mass spectrometer to measure the carbon and nitrogen isotopic ratios of hair (n = 134) and nail (n = 80) and the carbon isotopic ratios of breath (n = 184) from these communities, as well as the carbon and nitrogen isotopic ratios of some food samples from the Kenyan communities. RESULTS: We expand on the known range of δ13 C values in human hair through the hunter-gatherer Baka, with a diet based on C3 plants, and through the agriculturalist Luhya (Webuye), with a diet based on C4 plants. In addition, we found that the consumption of fish from East African lakes is difficult to detect isotopically due to the combined effects of high nitrogen isotopic ratios of plants and the low nitrogen isotopic ratios of fish. Finally, we found that some of the communities studied are markedly changing their diets through increasing sedentism and urbanisation. CONCLUSIONS: Our findings contribute substantially to the understanding of the environmental, demographic, and economic dynamics that affect the dietary landscape of different tropical populations of Africa. These results highlight the importance of studying a broader sample of human populations and their diet, with a focus on their precise context - from both isotopic and more general anthropological perspectives.


Assuntos
Isótopos de Carbono/análise , Cabelo/química , Unhas/química , Isótopos de Nitrogênio/análise , África , Testes Respiratórios , Dieta , Humanos , Espectrometria de Massas
13.
Proc Natl Acad Sci U S A ; 115(27): E6126-E6134, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29915032

RESUMO

To understand the diversity of human growth and development from an evolutionary point of view, there is an urgent need to characterize the life-history variables of vanishing forager societies. The small body size of the Baka pygmies is the outcome of a low growth rate during infancy. While the ages at sexual maturity, menarche, and first delivery are similar to those in other populations, fertility aspects are unknown. In the Le Bosquet district in Cameroon, thanks to systematic birth records kept from 1980 onwards, we were able to assign ages to individuals with certainty. This study, based on chronological records and on data collected from 2007 to 2017, presents life-history variables related to fertility and mortality among the Baka pygmies: total fertility rate, age-specific fertility rate, completed family size, reproductive span, age at menopause, and infant and juvenile mortality. The Baka present low infant and juvenile mortality, and their fertility pattern differs from that of other forager societies in the higher age-specific fertility rates found in the two lower age classes. Future studies will need to assess whether this particular pattern and the short interbirth interval are related to highly cooperative childrearing, which in the Baka is associated with slow growth. The fertility rate has fallen drastically since 2011, and this matches the arrival of cheap alcohol in the community. Our data provide a first-hand record of the impact of alcohol on fertility in a hunter-gatherer society which appears to be seriously compromising the survival of the Baka.


Assuntos
Bebidas Alcoólicas/efeitos adversos , Alcoolismo/mortalidade , População Negra , Mortalidade da Criança , Fertilidade , Mortalidade Infantil , Adolescente , Adulto , Camarões/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
14.
Sci Rep ; 8(1): 5536, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29674628

RESUMO

The earliest cranial surgery (trepanation) has been attested since the Mesolithic period. The meaning of such a practice remains elusive but it is evident that, even in prehistoric times, humans from this period and from the Neolithic period had already achieved a high degree of mastery of surgical techniques practiced on bones. How such mastery was acquired in prehistoric societies remains an open question. The analysis of an almost complete cow cranium found in the Neolithic site of Champ-Durand (France) (3400-3000 BC) presenting a hole in the right frontal bone reveals that this cranium underwent cranial surgery using the same techniques as those used on human crania. If bone surgery on the cow cranium was performed in order to save the animal, Champ-Durant would provide the earliest evidence of veterinary surgical practice. Alternatively, the evidence of surgery on this cranium can also suggest that Neolithic people practiced on domestic animals in order to perfect the technique before applying it to humans.


Assuntos
Experimentação Animal/história , Bovinos/cirurgia , Crânio/cirurgia , Trepanação/história , Trepanação/veterinária , Animais , Arqueologia , Fósseis , França , História Antiga , Cornos , Humanos , Lentes , Microscopia Eletrônica de Varredura , Crânio/lesões
15.
Am J Phys Anthropol ; 166(3): 671-681, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29566431

RESUMO

OBJECTIVES: Odontometric studies of African populations show high within-group variation in tooth size. Overall, North Africans exhibit smaller dimensions than groups from eastern and southern sub-Saharan regions, but no previous studies have analyzed the full dental metrics among extant African Pygmy hunter-gatherers and Bantu-speaking farmers. Furthermore, the population variability in tooth crown sizes from equatorial rainforest regions remains to be elucidated. MATERIALS AND METHODS: The mesiodistal and buccolingual diameters of the permanent teeth (I1-M2) were measured in vivo using high-resolution replicas from Baka Pygmies and Mvae and Yassa Bantu-speakers from Cameroon (western Africa). Analyses of variance were used to record sex-related and population-level differences in tooth sizes, and a principal component analysis of geometrically scaled measures was used to plot the odontometric variability among groups. RESULTS: Cameroonian Baka Pygmies differ in dental size from their Bantu-speaking neighbors. Molar teeth are larger in Pygmies than in Bantu individuals, while the anterior dentition is larger in the Bantu. Baka males exhibit significantly larger teeth than females, whereas sexual dimorphism in non-Pygmies is only present in the anterior dentition. DISCUSSION: Odontometric patterns and the degree of sexual dimorphism in dental size differ among Central African groups, indicating adaptation to their different forager and farmer lifestyles. In particular, the admixture of Bantu-speakers in Baka populations is smaller than that in other western Pygmy groups. The greater dental phenetic diversity in Baka compared to that of the smaller-toothed farmers suggests that ecogenetic and microevolutionary factors are influencing a particular divergence scenario.


Assuntos
População Negra/etnologia , Tamanho do Órgão/fisiologia , Dente/anatomia & histologia , Antropologia Física , Fazendeiros , Feminino , Humanos , Masculino , Odontometria , Caracteres Sexuais
16.
Sci Rep ; 6: 27405, 2016 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-27305976

RESUMO

Life history variables (LHV) in primates are closely correlated with the ages of tooth eruption, which are a useful proxy to predict growth and development in extant and extinct species. However, it is not known how tooth eruption ages interact with LHV in polymorphic species such as modern humans. African pygmies are at the one extreme in the range of human size variation. LHV in the Baka pygmies are similar to those in standard populations. We would therefore expect tooth eruption ages to be similar also. This mixed (longitudinal and cross-sectional) study of tooth eruption in Baka individuals of known age reveals that eruption in all tooth classes occurs earlier than in any other human population. Earlier tooth eruption can be related to the particular somatic growth in the Baka but cannot be correlated with LHV. The link between LHV and tooth eruption seems disrupted in H. sapiens, allowing adaptive variations in tooth eruption in response to different environmental constraints while maintaining the unique human life cycle.


Assuntos
Pan paniscus/fisiologia , Erupção Dentária/fisiologia , Dente/fisiologia , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Primatas/fisiologia , Adulto Jovem
17.
PLoS One ; 8(12): e84804, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24367696

RESUMO

Pygmy hunter-gatherers from Central Africa have shared a network of socioeconomic interactions with non-Pygmy Bantu speakers since agropastoral lifestyle spread across sub-Saharan Africa. Ethnographic studies have reported that their diets differ in consumption of both animal proteins and starch grains. Hunted meat and gathered plant foods, especially underground storage organs (USOs), are dietary staples for pygmies. However, scarce information exists about forager-farmer interaction and the agricultural products used by pygmies. Since the effects of dietary preferences on teeth in modern and past pygmies remain unknown, we explored dietary history through quantitative analysis of buccal microwear on cheek teeth in well-documented Baka pygmies. We then determined if microwear patterns differ among other Pygmy groups (Aka, Mbuti, and Babongo) and between Bantu-speaking farmer and pastoralist populations from past centuries. The buccal dental microwear patterns of Pygmy hunter-gatherers and non-Pygmy Bantu pastoralists show lower scratch densities, indicative of diets more intensively based on nonabrasive foodstuffs, compared with Bantu farmers, who consume larger amounts of grit from stoneground foods. The Baka pygmies showed microwear patterns similar to those of ancient Aka and Mbuti, suggesting that the mechanical properties of their preferred diets have not significantly changed through time. In contrast, Babongo pygmies showed scratch densities and lengths similar to those of the farmers, consistent with sociocultural contacts and genetic factors. Our findings support that buccal microwear patterns predict dietary habits independent of ecological conditions and reflect the abrasive properties of preferred or fallback foods such as USOs, which may have contributed to the dietary specializations of ancient human populations.


Assuntos
Dieta , Etnicidade , Transtornos do Crescimento , Desgaste dos Dentes/patologia , Adaptação Biológica/fisiologia , África Central , Técnica de Moldagem Odontológica , Humanos , Microscopia Eletrônica de Varredura , Análise de Componente Principal
18.
PLoS One ; 7(4): e35917, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22558270

RESUMO

Modern human populations differ in developmental processes and in several phenotypic traits. However, the link between ontogenetic variation and human diversification has not been frequently addressed. Here, we analysed craniofacial ontogenies by means of geometric-morphometrics of Europeans and Southern Africans, according to dental and chronological ages. Results suggest that different adult cranial morphologies between Southern Africans and Europeans arise by a combination of processes that involve traits modified during the prenatal life and others that diverge during early postnatal ontogeny. Main craniofacial changes indicate that Europeans differ from Southern Africans by increasing facial developmental rates and extending the attainment of adult size and shape. Since other studies have suggested that native subsaharan populations attain adulthood earlier than Europeans, it is probable that facial ontogeny is linked with other developmental mechanisms that control the timing of maturation in other variables. Southern Africans appear as retaining young features in adulthood. Facial ontogeny in Europeans produces taller and narrower noses, which seems as an adaptation to colder environments. The lack of these morphological traits in Neanderthals, who lived in cold environments, seems a paradox, but it is probably the consequence of a warm-adapted faces together with precocious maturation. When modern Homo sapiens migrated into Asia and Europe, colder environments might establish pressures that constrained facial growth and development in order to depart from the warm-adapted morphology. Our results provide some answers about how cranial growth and development occur in two human populations and when developmental shifts take place providing a better adaptation to environmental constraints.


Assuntos
População Negra , Crânio/crescimento & desenvolvimento , População Branca , Adolescente , Adulto , África Austral/etnologia , Análise de Variância , Pontos de Referência Anatômicos , Cefalometria , Criança , Pré-Escolar , Europa (Continente)/etnologia , Face/anatomia & histologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Tamanho do Órgão , Análise de Componente Principal , Crânio/anatomia & histologia , Adulto Jovem
19.
Am J Phys Anthropol ; 148(4): 632-40, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22623291

RESUMO

Recent studies suggest that the hypodigms representing the two earliest Australopithecus (Au. anamensis and Au. afarensis) form an ancestor-descendant lineage. Understanding the details of this possible transition is important comparative evidence for assessing the likelihood of other examples of ancestor-descendant lineages within the hominin clade. To this end we have analyzed crown and cusp base areas of high resolution replicas of the mandibular molars of Au. anamensis (Allia Bay and Kanapoi sites) and those of Au. afarensis (Hadar, Laetoli, and Maka). We found no statistically significant differences in crown areas between these hypodigms although the mean of M(1) crowns was smaller in Au. anamensis, being the smallest of any Australopithecus species sampled to date. Intraspecies comparison of the areas of mesial cusps for each molar type using Wilcoxon signed rank test showed no differences for Au. anamensis. Significant differences were found between the protoconid and metaconid of Au. afarensis M(2)s and M(3)s. Furthermore, the area formed by the posterior cusps as a whole relative to the anterior cusps showed significant differences in Au. afarensis M(1)s and in Au. anamensis M(2)s but no differences were noted for M(3)s of either taxon. Developmental information derived from microstructural details in enamel shows that M(1) crown formation in Au. anamensis is similar to Pan and shorter than in H. sapiens. Taken together, these data suggests that the overall trend in the Au. anamensis-Au. afarensis transition may have involved a moderate increase in M(1) crown areas with relative expansion of distal cusps.


Assuntos
Fósseis , Hominidae/anatomia & histologia , Dente Molar/anatomia & histologia , Coroa do Dente/anatomia & histologia , Animais , Antropologia Física , Variações Dependentes do Observador , Estatísticas não Paramétricas
20.
J Anthropol Sci ; 89: 153-60, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21757792

RESUMO

We present a new method to determine Sr/Ca changes in hard dental tissues based on laser ablation and spectroscopic detection. By using femtosecond Laser Induced Breakdown Spectroscopy (fs-LIBS), we micro mapped the relative amount of strontium in the enamel of three human lower third molar. We also analyzed the Sr/Ca ratio along the striae of Retzius. Results show that microlibs allows detection of variation in relative Sr/Ca ratio through enamel. The same values of Sr/Ca ratio were found along a single stria. The method has a precision better than 95% and is sensitive enough to detect Sr/Ca ratio variations among striae and within stria. Fs-LIBS generates information in a fast and simple way that can be used by non-specialists to make inferences about diet or mobility in human populations and fossil hominids.


Assuntos
Esmalte Dentário/química , Análise Espectral/métodos , Estrôncio/análise , Fatores Etários , Antropologia Física , Cálcio/análise , Fósseis , Humanos , Dente Serotino/anatomia & histologia , Dente Serotino/química , Dente Serotino/crescimento & desenvolvimento , Sensibilidade e Especificidade
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