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1. Calculus and survivorship in medieval London: The association between dental disease and a demographic measure of general health

   https://doi.org/10.1002/ajpa.23772  

   Yaussy, Samantha L. ; DeWitte, Sharon N. ( January 2019 , American Journal of Physical Anthropology)

   Dental plaque is associated with a variety of systemic diseases and mortality risks in living populations. However, bioarchaeologists have not fully investigated the mortality risks associated with plaque (or its mineralized form, calculus) in the past. This study examines the relationship between survivorship and calculus in a medieval skeletal sample.

   Our sample (n = 1,098) from four medieval London cemeteries,c. 1000–1540 CE, includes people who died under attritional (normal) and catastrophic (famine and plague) conditions. The associations between age and the presence of dental calculus on the permanent left first mandibular molar are assessed using binary logistic regression and Kaplan–Meier survival analysis.

   The regression results indicate a significant negative relationship between age and calculus presence for individuals of all ages who died under normal mortality conditions and for adults who died under both normal and catastrophic conditions. Survival analysis reveals decreased survivorship for people of all ages with calculus under normal mortality conditions. Similarly, during conditions of catastrophic mortality, adult males with calculus suffered reduced survivorship compared to males without it, though there was no difference in survivorship between adult females with and without calculus.

   These results suggest that, as in modern populations, calculus accumulation in the inhabitants of medieval London reflects a greater risk of premature death. The evaluation of calculus, a potential measure of underlying frailty, in the context of a demographic measure of general health suggests that it might provide insights into health in past populations.

    

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2. Female swamp sparrows do not show evidence of discriminating between the songs of peak‐aged and senescent males

   https://doi.org/10.1111/eth.13102  

   Zipple, Matthew N. ; Peters, Susan ; Searcy, William A. ; Nowicki, Stephen ( October 2020 , Ethology)

   Sexual selection theory predicts that females face contrasting selection pressures when choosing the age of their mate. On the one hand, older males have demonstrated their ability to survive and they may be more experienced than younger males. At the same time, however, younger males are expected to have accumulated fewer deleterious mutations in their germline as compared to older males. These contrasting pressures on female preference may result in a preference for intermediate‐aged males. A preference for males of a particular age can only be expressed, however, if females are able to identify males of different ages. We have previously shown that male swamp sparrows display age‐related changes in vocal quality, such that males display sharp increases in vocal quality in early adulthood, followed by gradual senescent declines thereafter. We have also shown that territorial males discriminate these within‐individual differences, giving stronger aggressive responses to songs of peak‐aged males than to those of senescent males. Here, we use a copulation solicitation assay to test whether females also discriminate these within‐signaler markers of senescence in song. Contrary to our prediction, females did not show any evidence of discriminating between songs recorded from peak‐aged males as compared to songs from the same males following song senescence. We suggest that this difference in demonstrated discrimination between males and females may be the result of the two sexes attending to different song characteristics.

    

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3. The intersections of industrialization: Variation in skeletal indicators of frailty by age, sex, and socioeconomic status in 18th‐ and 19th‐century England

   https://doi.org/10.1002/ajpa.23881  

   Yaussy, Samantha L. ( June 2019 , American Journal of Physical Anthropology)

   Intersectionality theory argues that various categories of identity and forms of systemic oppression interact and produce inequalities in resource access, economic opportunities, and health outcomes. However, there has been little explicit engagement with this theory by bioarchaeologists examining disparate health outcomes in the past. This study examines the associations among frailty, age at death, sex, and socioeconomic status (SES) in 18th‐ and 19th‐century England.

   The sample for this study comes from four industrial‐era cemeteries from England, ca. 1711–1857. The associations among adult age (18+ years), SES, sex, and three skeletal indicators of stress (dental enamel hypoplasia [DEH,n= 293], cribra orbitalia [CO,n= 457], periosteal lesions [PNB,n= 436]) are examined using hierarchical log‐linear analysis.

   Significant interactions existed among the variables examined for two skeletal indicators: high SES females had lower frequencies of CO relative to other groups and males between ages 30–45 years exhibited higher frequencies of PNB compared to females or males of older or younger ages, regardless of SES. Additionally, sex and SES were consistently associated with age at death.

   These results suggest that patterns of stress indicators cannot be examined solely across unilateral axes of age, SES, or sex. Intersecting axes of privilege, marginalization, and structural oppression may have buffered high SES females from some negative health outcomes (CO) while predisposing them to others (risk of maternal mortality). Likewise, the hazardous working conditions relegated to adult males may have heightened the risk of injury, infection, and death for middle‐aged men in industrial‐era England.

    

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4. Three‐dimensional anatomy of the anthropoid bony pelvis

   https://doi.org/10.1002/ajpa.23425  

   Ward, Carol V. ; Maddux, Scott D. ; Middleton, Emily R. ( February 2018 , American Journal of Physical Anthropology)

   Pelvic form is hypothesized to reflect locomotor adaptation in anthropoids. Most observed variation is found in the ilium, which traditionally is thought to reflect thoracic and shoulder morphology. This article examines the articulated bony pelvis of anthropoids in three dimensions (3D) to test hypothesized variation in pelvic anatomy related to overall torso form.

   Sixty landmarks were collected on articulated pelves from 240 anthropoid individuals. Landmark data were subjected to a Generalized Procrustes Analysis. Principal Components Analysis was used to identify trends among taxa. Linear metrics were extracted, and bivariate allometric analysis was used to compare intergroup differences and scaling trends of specific dimensions.

   The combination of 3D and bivariate allometric analysis demonstrates a complex pattern of locomotor/phylogenetic and allometric influences on pelvic morphology. Apes have relatively narrower dorsal interiliac spacing than do most monkeys, with relatively smaller spinal muscle attachment areas but only minimally wider ventral bi‐iliac breadths. Hylobatids and atelids have a relatively more cranial position of their sacra than do other taxa, and hylobatids and cercopithecids relatively more retroflexed ischia. Within groups, the three pelvic joints (lumbosacral, sacroiliac, and hip) become relatively closer together with increasing body size.

   A three‐dimensional consideration of the articulated pelvis in anthropoids reveals determinants of pelvic variation not previously appreciated by studies of isolated hipbones. This study provides no support for the hypothesis that the ape pelvis is mediolaterally broader than that of monkeys in relative terms, as would be expected if iliac shape is related to hypothesized differences in thoracic breadth and shoulder orientation. Instead, apes, especially great apes, have relatively narrow sacra and longer lower pelves, related to their shorter, stiffer lumbar spines and torsos. This difference, coupled with strong positive allometry of iliac breadth and negative allometry of key pelvic lengths, along with some variation in ischial morphology in certain taxa, explains much of the variation in pelvic form among anthropoid primates.

    

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5. Sex‐biased parental investment and female wealth accumulation in ancient California

   https://doi.org/10.1002/ajpa.24806  

   Greenwald, Alexandra M. ; Burns, Gregory R. ; Eerkens, Jelmer W. ; Bartelink, Eric J. ; Leventhal, Alan ; Arellano, Monica V. ( July 2023 , American Journal of Biological Anthropology)

   The mortuary record at Middle Period siteKalawwasa Rummeytak(CA‐SCL‐134) (2600‐1225 cal BP) in California's southern Santa Clara Valley shows pronounced wealth inequality;Olivellashell bead wealth, as well as other grave goods, are concentrated in the burials of several older adult females. The concentration of wealth among women, along with regional strontium isotopic evidence of male‐biased residential shifts in early adulthood, suggests a matrilineal kinship system that practiced matrilocal post‐marital residence patterns. We suggest local resource enhancement effects incentivized keeping women in their natal communities and investing more in female offspring.

   With the consent of, and in collaboration with, the Muwekma Ohlone Tribe of the San Francisco Bay Area, this paper employs isotopic analysis (δ¹⁵N andδ¹³C,⁸⁶Sr/⁸⁷Sr) to examine duration of exclusive breastfeeding, weaning age (complete cessation of breastmilk consumption), early childhood diet, and lifetime residential mobility of individuals interred atKalawwasa Rummeytakto test the assumption that the site inhabitants favored matrilocality and that female offspring received greater levels of investment in groups with female wealth/status attainment. First molars, third molars, and bone was sampled from 22 individuals.

   The average weaning age for females atKalawwasa Rummeytakis 36.3 months ± 9.7 (1 SD), or just over 3 years. The average weaning age for males is 31.2 ± 7.9 months (1 SD), or about 2.6 years. Infants at the site were provisioned with supplemental foods dominated by C₃plants and terrestrial herbivores, as well as anadromous fish. After weaning, individuals consumed a diet dominated by acorns, C₃plants, and terrestrial herbivores, with periodic inclusion of anadromous fish. 30% of the sampled population of females exhibit local first molar⁸⁷Sr/⁸⁶Sr values, suggesting thatKalawwasa Rummeytakis their natal community. None of the males interred at the site are locals.

   Despite the small sample size often unavoidable in archaeological contexts, we find possible female‐biased parental investment strategies. Cessation of breastfeeding (weaning) was, on average, 5 months earlier for males compared to females. There are no differences between females and males in the consumption of supplemental or post‐weaning foods. Strontium data suggest a flexible postmarital residence system that favored matrilocality. This may have incentivized greater investment in female offspring.

    

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