Coming of age in Roman Britain: Osteological evidence for pubertal timing

An assessment of puberty status in adolescents from the European Upper Paleolithic

Childhood and adolescence are two life-history stages that are either unique to humans, or significantly expanded in the human life course relative to other primates. While recent studies have deepened our knowledge of childhood in the Upper Paleolithic, adolescence in this period remains understudied. Here, we use bioarchaeological maturational markers to estimate puberty status of 13 Upper Paleolithic adolescents from sites in Russia, Czechia, and Italy to 1) evaluate the feasibility of the application of bioarchaeological puberty assessment methods to Upper Paleolithic (Homo sapiens) skeletal individuals, 2) estimate the timing and tempo of puberty in Upper Paleolithic adolescents compared to other archaeological populations analyzed using the same method, and 3) characterize adolescence in the Upper Paleolithic by contextualizing the results of this puberty assessment with data on individual and population-level health, morbidity and burial practices. Our results revealed that while puberty had begun by 13.5 years of age for the majority of individuals, there was a lot of variability, with the adolescents from Arene Candide (AC1 and AC16), both aged around 16 years when they died, taking several years longer to progress through puberty than their peers. Assessing the age of menarche was challenging due to the paucity of female adolescents, but based on the available evidence, it appears to have occurred between 16 and 17 years of age. For some, full adulthood had been achieved by 17-22 years, similar to the patterns seen in modern wealthy countries and in advance of historic populations living in urbanized environments. The bioarchaeological analysis of puberty among Upper Paleolithic adolescents has important implications for the study of the emergence of adolescence within human-life histories, as well as for understanding the developmental plasticity of sexual maturation across past and present human populations.

Proposed complementary osteological indicators: Advancing the estimation of puberty stages in Bioarcheology

OBJECTIVES

The study of puberty is a well-established area of bioarcheological research, which greatly enhances our understanding of adolescence and growth in the past. Since the publications of Shapland and Lewis' works, which have become "standards" for estimating puberty in skeletal material, no additional osteological indicators of puberty have been proposed. Nevertheless, clinical practice constantly develops skeletal maturation markers that could be useful in bioarcheology. This study aims to assess the applicability and reliability of novel puberty indicators as a complementary tool to estimate puberty in skeletal remains.

MATERIALS AND METHODS

Four new maturation markers including spheno-occipital synchondrosis, humeral head ossification, calcaneal apophysis ossification, and mandibular premolar mineralization were selected and applied to a sample of 85 adolescents from pre-Roman southern Italy (Pontecagnano, 7th-4th BCE).

RESULTS

Despite some limits in adapting the original clinical methods to osteoarcheological material, the use of these novel skeletal indicators had moderate to excellent scoring repeatability and an overall high agreement with the puberty and menarche status previously estimated with standard methods. These results encourage us to apply these markers in bioarcheology. In some cases, minor adaptations of the original scoring systems are suggested to enhance reliability.

DISCUSSION

Including the proposed indicators in routine puberty data collection allows us to refine puberty estimation and improve the ability to identify key growth milestones in poorly preserved skeletons. Further application to osteological collections with diverse chronology and geographical differences is needed to assess how and to what extent the newly proposed maturation markers perform.

Menarche at Amarna: Timing and the further implications

OBJECTIVE

This article examines skeletal development in non-elite individuals from Amarna to identify the age of menarche.

MATERIALS AND METHODS

The total sample (n = 267; 65 female, 39 male, 163 indeterminate) was examined for six variables indicative of the pubertal stage (mineralization of the mandibular canine root [n = 46], distal radius fusion [n = 227], proximal ulna fusion [n = 220], distal humerus fusion [n = 237], presence of the iliac crest epiphysis [n = 24], iliac crest fusion [n = 199]). Age and sex estimates are based on standard criteria for dental development and eruption, cranial and pelvic morphology, and post-cranial metric analysis.

RESULTS

The iliac crest epiphysis is rarely present before age 15 years. Beginning fusion of the distal radius and iliac crest suggests that by age 19, most individuals have entered the maturation phase, providing book ends for the timing of menarche. Variables elucidating the peak height velocity (proximal ulna and distal humerus fusion) narrow that span and suggest menarche is achieved around 15-17 years for most individuals, with a broader estimate of 14-19 years encompassing the known diversity in timing of menarche.

DISCUSSION

Menarche is commonly cited as an indicator of adult status. The observed later entrance into this life stage, and the associated reduced fertility, has broader implications for understanding of economic, social, biological, and demographic patterns observed at Amarna and among different social groups in the ancient city, as well as individual life histories.

Exploring adolescence as a key life history stage in bioarchaeology

Adolescence is a unique period in the life history of an individual. It is characterized by a myriad of changes that bioarchaeologists are only just coming to appreciate, related to sexual maturation, linear growth, immunological transformation, and emotional and cognitive development. New methods allow us to measure this age of transition through the stages of the adolescent growth, as a proxy for the physical development associated with sexual maturation (puberty). This review outlines ways bioarchaeologists may draw on research developments from the fields of human biology, evolutionary theory and neurobiology to advance a more holistic approach to the study of adolescence in the past. It considers current theoretical and analytical approaches to highlight the research potential of this critical stage of life history. This synthesis integrates the most recent research in the medical sciences concerned with body and brain development, and outlines the biological processes involved with sexual and physical maturation of the adolescent. The goal of this review is to help inform potentially rewarding areas of research that bioarchaeologists can contribute to and draw from, as well as the challenges and limitations, theoretical and methodological questions, and ways in which we can develop the study of adolescence in the discipline going forward.

Interpreting error in the estimation of skeletal growth profiles from past populations: An example demonstrating skeletal growth in historic African American communities

OBJECTIVES

The study of growth in the past is a critical component of bioarcheological analyses. However, our understanding of growth in the past is subject to a number of methodological challenges. This study aims to model the skeletal growth of past populations by considering the challenges associated with the data collection process and the challenges associated with the age estimation procedures.

MATERIALS AND METHODS

We use skeletal remains from two historic African American cemeteries in the American South to model femoral diaphyseal length-for-age. We estimate the age of each individual using dental development techniques and present growth curves as both a product of the maximum likelihood (MLE) age estimate and the estimated posterior age distribution. Growth was compared against a reference sample from the University of Colorado Child Research Council Study.

RESULTS

The results of our analyses showed that femoral diaphyseal length in two historic African American communities is small-for-estimated age as compared to a modern reference sample. However, the magnitude and characterization of this difference is variable when taking into account the broader posterior age distribution.

DISCUSSION

Both samples may be small-for-age due to physiological stress associated with racism, inequality, and the compounding effects of early urbanization. However, the interpretation of growth in the past is muddled when considering the relationship between the study sample and the reference sample, when accounting for uncertainty in the age estimation procedure, and the error-inducing steps taken during the data collection process. Future interpretation of skeletal growth in the past must include a full account of the possible sources of error in order to present an accurate representation of growth.

Approaches to osteoporosis in paleopathology: How did methodology shape bone loss research?

OBJECTIVE

This paper will review how different methods employed to study bone loss in the past were used to explore different questions and aspects of bone loss, how methodology has changed over time, and how these different approaches have informed our understanding of bone loss in the past.

MATERIALS AND METHODS

A review and discussion is conducted on research protocols and results of 84 paleopathology publications on bone loss in archaeological skeletal collections published between 1969 and 2021.

CONCLUSIONS

The variety in research protocols confounds accurate meta-analysis of previously published research; however, more recent publications incorporate a combination of bone mass and bone quality based methods. Biased sample selection has resulted in a predominance of European and Medieval publications, limiting more general observations on bone loss in the past. Collection of dietary or paleopathological covariables is underemployed in the effort to interpret bone loss patterns.

SIGNIFICANCE

Paleopathology publications have demonstrated differences in bone loss between distinct archaeological populations, between sex and age groups, and have suggested factors underlying observed differences. However, a lack of a gold standard has encouraged the use of a wide range of methods. Understanding how this array of methods effects results is crucial in contextualizing our knowledge of bone loss in the past.

LIMITATIONS

The development of a research protocol is also influenced by available expertise, available equipment, restrictions imposed by the curator, and site-specific taphonomic aspects. These factors will likely continue to cause (minor) biases even if a best practice can be established.

SUGGESTIONS FOR FUTURE RESEARCH

Greater effort to develop uniform terminology and operational definitions of osteoporosis in skeletal remains, as well as the expansion of time scale and geographical areas studied. The Next-Generation Sequencing revolution has also opened up the possibility of ancient DNA analyses to study genetic predisposition to bone loss in the past.

Toward a bioarchaeology of urbanization: Demography, health, and behavior in cities in the past

Urbanization is one of the most important settlement shifts in human history and has been the focus of research within bioarchaeology for decades. However, there have been limited attempts to synthesize the results of these studies in order to gain a broader perspective on whether or how urbanization affects the biology, demography, and behavior of humans, and how these potential effects are embodied in the human skeleton. This paper outlines how bioarchaeology is well-suited to examine urbanization in the past, and we provide an overview and examples of three main ways in which urbanization is studied in bioarchaeological research: comparison of (often contemporaneous) urban and rural sites, synchronic studies of the variation that exists within and between urban sites, and investigations of changes that occur within urban sites over time. Studies of urbanization, both within bioarchaeology and in other fields of study, face a number of limitations, including a lack of a consensus regarding what urban and urbanization mean, the assumed dichotomous nature of urban versus rural settlements, the supposition that urbanization is universally bad for people, and the assumption (at least in practice) of homogeneity within urban and rural populations. Bioarchaeologists can address these limitations by utilizing a wide array of data and methods, and the studies described here collectively demonstrate the complex, nuanced, and highly variable effects of urbanization.

Neurobiology of puberty and its disorders

Puberty, which in humans is considered to include both gonadarche and adrenarche, is the period of becoming capable of reproducing sexually and is recognized by maturation of the gonads and development of secondary sex characteristics. Gonadarche referring to growth and maturation of the gonads is fundamental to puberty since it encompasses increased gonadal steroid secretion and initiation of gametogenesis resulting from enhanced pituitary gonadotropin secretion, triggered in turn by robust pulsatile GnRH release from the hypothalamus. This chapter reviews the development of GnRH pulsatility from before birth until the onset of puberty. In humans, GnRH pulse generation is restrained during childhood and juvenile development. This prepubertal hiatus in hypothalamic activity is considered to result from a neurobiological brake imposed upon the GnRH pulse generator resident in the infundibular nucleus. Reactivation of the GnRH pulse generator initiates pubertal development. Current understanding of the genetics and physiology of the brake will be discussed, as will hypotheses proposed to account for timing the resurgence in pulsatile GnRH and initiation of puberty. The chapter ends with a discussion of disorders associated with precocious or delayed puberty with a focus on those with etiologies attributed to aberrant GnRH neuron anatomy or function. A pediatric approach to patients with pubertal disorders is provided and contemporary treatments for both precocious and delayed puberty outlined.

Coming of age in the Netherlands: An osteological assessment of puberty in a rural Dutch post-medieval community

OBJECTIVES

The objective of this study is to apply pubertal stage estimation methods to a sample from a rural community: the post-medieval Dutch skeletal collection from Middenbeemster. Puberty is a key developmental period involving transition to physical adulthood with broad societal relevance through its impact on fertility, morbidity, and mortality.

MATERIALS AND METHODS

Individuals (n = 55), including 27 of known sex and age-at-death, between the ages of 8 and 25 years were assessed for six skeletal markers indicative of pubertal growth spurt. Recent novel osteoarchaeological methods from Shapland and Lewis are used to reconstruct the timing and duration of pubertal stages.

RESULTS

Pubertal acceleration occurred earlier in females (10.38 years, n = 8) than males (13.30 years, n = 6), whereas maturation occurred later in males (21.36 years, n = 11) than females (19.30 years, n = 5). Onset appears earlier and completion later compared to other archaeological skeletal samples with osteoarchaeological evidence of puberty. Age shortly after menarche was reconstructed at 20.45 years, substantially later than historic records and bioarchaeological research reports suggest.

CONCLUSION

This early onset and late completion caused a "stretch" of the overall duration of puberty compared to other collections, especially of the last three stages. This prolonged development is reflected in historically known social expectations for the Netherlands, for example, that marriage and children should not occur before about 22-23 years of age. Increasing the range of past peoples with puberty stage reconstruction will permit more insightful interpretations of the biological and cultural patterns of this important life stage.

Association of body image dissatisfaction with body mass index trajectory: the Adolescent Nutritional Assessment Longitudinal Study cohort

ABSTRACT Objective To examine the association of body image dissatisfaction (BID) with body mass index (BMI) trajectory among students from a metropolitan area of Rio de Janeiro. Methods Data were analyzed for 809 middle school students followed from 2010 to 2013, and 1131 high school students followed from 2010 to 2012. BID was assessed using a body silhouettes scale. Type of school (public and private) was used as a proxy of socioeconomic status. Results In the middle school cohort, girls from private schools who wanted to have smaller and bigger silhouettes gained fewer BMI units than those who were satisfied with their body image ( p < 0.05). In the high school, girls from private schools who wished to have bigger and smaller silhouettes experienced greater BMI increase than girls who were satisfied with their body image ( p < 0.05). Also, in the high school cohort, boys from public schools who wished to have smaller and bigger silhouettes experienced smaller BMI increase than boys who were satisfied ( p < 0.05). Conclusion BID may be related to the BMI trajectory in girls from private schools and in boys from public schools.

Medieval menarche: Changes in pubertal timing before and after the Black Death

OBJECTIVES

Bioarcheological evidence suggests stature increased in males but decreased in females after the Black Death (1348-1350 CE). Because tradeoffs between growth and reproduction can result in earlier ages at menarche and lower limb length, we assess menarcheal age between 1120 and 1540 CE to better understand the health of medieval adolescent females before and after the plague.

MATERIALS AND METHODS

Our sample comprises 74 adolescent females from St. Mary Spital, London (1120-1540 CE) within the age range during which menarche occurs (10-25 years). They were assessed as being pre- or post-menarcheal and divided into three groups: Early Pre-Black Death (n = 13), Late Pre-Black Death (n = 38), and Post-Black Death (n = 23). Changes in the ages of pre- and post-menarcheal females were assessed using Mann-Whitney tests.

RESULTS

The average age of post-menarcheal females increased from the Early- to Late Pre-Black Death periods and declined after the Black Death.

CONCLUSIONS

Short stature can reflect unfavorable growth environments, while younger menarcheal age indicates improved living conditions. The paradoxical pattern of female, but not male, stature reduction after the Black Death might reflect the association of early menarche with lower limb length and signal that adolescent females experienced improved health conditions after the epidemic. Our focus on pre- and post-menarche within a limited age span provides a novel approach for inferring average ages of menarche over time. Pathways to skeletal development and reproductive investment are part of an integrated system, providing a bridge between life history research in bioarchaeology and human biology.

Life and death at the "The Land of Three Lakes": Revisiting the non-adults from Roman Aventicum, Switzerland (1st-3rd century CE)

The study of Roman childhood has been the focus of research primarily using documentary and archaeological evidence, while relatively few non-adult skeletal assemblages have been analyzed. This paper presents the study of 93 non-adult individuals from four cemeteries in the Roman (1st-3rd c. CE) civitas capital of Aventicum (Avenches), Switzerland. The results of the analysis offer a new bioarchaeological perspective on mortality and disease patterns during childhood in Roman Switzerland, adding to the discussion regarding living conditions in the urban centers at the periphery of the Roman Empire. This study also highlights the importance of studying perinates in archaeological populations, since the current research inform us about the experiences of mothers and their offspring in Aventicum. The mortality and disease patterns of the perinates, representing 71% of the total non-adult sample (66/93), suggest that pregnancy and the time around birth were extremely challenging at Aventicum. It is argued that environmental constraints, e.g. the risk of infectious diseases such as malaria and natural phenomena such as recurring floods resulting in resources scarcity, could have considerably affected the mother-fetus pair in this urban settlement.