Sex estimation methods commonly used in osteoarchaeology involve the pelvis and skull. If the pelvis, cranium or other big-sized bones are damaged or cannot be found in a burial, new methods for...Show moreSex estimation methods commonly used in osteoarchaeology involve the pelvis and skull. If the pelvis, cranium or other big-sized bones are damaged or cannot be found in a burial, new methods for estimating sex are needed. This study aims to determine the degree of sexual dimorphism from the first proximal hand phalanges, in order to explore the possibility of using this particular bone for sex estimation. The sample used in this study was taken from Middenbeemster skeletal collection housed in Human Osteoarchaeology Laboratory, Leiden University. The skeletal collection from the 17th - 19th century was chosen because it has individuals of known sex and age. A total of 103 first proximal hand phalanges obtained from 64 adult individuals (22 males and 42 females) were used in this study. There were seven measurements used to analyze the degree of sexual dimorphism, including maximal length and diaphyseal and epiphyseal widths, both mediolaterally and anteroposteriorly. The degree of sexual dimorphism in the first proximal hand phalanx of Middenbeemster skeletal collection is up to 22.38%, indicated by left APWM. The lowest degree of sexual dimorphism is shown by the left ML. Five out of seven measurements used in this study show the left side has a higher degree of sexual dimorphism than the right. The results of this study indicate that the first proximal hand phalanx can potentially be used for sex estimation.Show less
The most accurate ageing methods for non-adult individuals are based on dental development and eruption. However, archaeological skeletal remains are often fragmented or incomplete, as a result of...Show moreThe most accurate ageing methods for non-adult individuals are based on dental development and eruption. However, archaeological skeletal remains are often fragmented or incomplete, as a result of which teeth may be lost or severely damaged. Recently, Primeau et al. (2016) developed a method to estimate age-at-death of non-adults with the use of the diaphyseal length for all major long bones. This study aims to evaluate the accuracy and reliability of the quadratic regression formulae on a post-medieval Dutch population. Long bone lengths were measured for a total of 61 individuals from the Middenbeemster skeletal collection, ranging from birth to 21 years of age. Regression ages were assigned, and subsequently compared to the known ages of 38 individuals, and estimated dental ages of 23 individuals. The results show an overall high accuracy of the method in when all age groups are combined, but inaccurate regression ages were produced for the long bones of the infants, and some of the bones of the children in the sample. This discrepancy might be partly explained by a difference in size and varying growth rates between the Middenbeemster and Danish individuals. For the juvenile and adolescent age categories, almost no significant differences were found, which suggests that the regression formulae can be used to estimate age-at-death accurately for non-adults above the age of 6 years.Show less
The occurrence and aetiology of congenitally absent third molars is widely researched in modern human populations. Previous research on third molar agenesis has, however, seldom been conducted on...Show moreThe occurrence and aetiology of congenitally absent third molars is widely researched in modern human populations. Previous research on third molar agenesis has, however, seldom been conducted on medieval populations, and archaeological research on other time periods has focussed on either agenesis patterns, prevalence within a population, or relations to dental wear. Osteoarchaeology can contribute to understanding third molar agenesis in a way that exceeds temporal and geographical boundaries, and therefore it can contribute to unravelling different aetiological contributors of third molar agenesis. This research is about third molar agenesis in the Late Medieval Dutch skeletal collections of Klaaskinderkerke (rural) and Alkmaar (urban) in order to gain insight into congenitally absent third molars during the Dutch Late Medieval period. To enhance knowledge about third molar agenesis, this study conducts prevalence and metric analyses of the jaws in relation to third molar agenesis patterns. The main question is ‘Do sex, size and robustness of the mandible and the maxilla, and the place in the jaw (mandible versus maxilla), relate to the agenesis, impaction, or presence of the third molar in a Late Medieval Dutch sample?’ To answer the research questions, 19 mandibular and 9 maxillary measurements are used to quantify size and robustness. Radiological examination is used to differentiate between third molar agenesis and impaction. Statistical analyses explore the relationships between category and metric variables and third molar agenesis. The results show that impaction of the third molar was not present in the two late medieval sites. The frequency of third molar agenesis is insignificantly higher for females (36.8%) than for males (29.4%). Congenitally absent third molars are insignificantly more often observed in the mandibles than in the maxillae (29.7% versus 25.0%). Congenitally absent third molars were observed significantly more frequently in the Alkmaar collection (46.5%) than in the Klaaskinderkerke (25.5%) sample. These differences may be related to differences in environment, genetic variation, or ways of living. The socioeconomic background is similar for both sites, and should not be a contributing factor. The statistical results indicate that third molar agenesis is to some extent related to size and robustness of the jaws, but only a few measurements correlate with agenesis. All correlating measurements differ between males and females, except for Body Height. The contribution of the current study to understanding the development of third molar agenesis is that it provides osteoarchaeological data on a (sex specific) relationship between size and robustness of the jaws and third molar agenesis in the Dutch Middle Ages.Show less
