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1. Growth trajectories in wild geladas ( Theropithecus gelada )

   https://doi.org/10.1002/ajp.22535  

   Lu, Amy ; Bergman, Thore J. ; McCann, Colleen ; Stinespring‐Harris, Ashley ; Beehner, Jacinta C. ( March 2016 , American Journal of Primatology)

   Life history and socioecological factors have been linked to species‐specific patterns of growth across female vertebrates. For example, greater maternal investment in offspring has been associated with more discrete periods of growth and reproduction. However, in primates it has been difficult to test such hypotheses because very few studies have obtained growth measurements from wild populations. Here we utilize a promising noninvasive photogrammetric method—parallel lasers—to examine shoulder‐rump (SR) growth in a wild primate, the gelada (Theropithecus gelada, Simien Mountains National Park, Ethiopia). In this species, a graminivorous diet coupled with high extrinsic infant mortality risk suggests that maternal investment in neonates is low. Therefore, in contrast with other closely related papionins, we expected female geladas to exhibit less discrete periods of growth and reproduction. For both sexes, we compared size‐for‐age patterns (N = 154 females;N = 110 males) and changes in growth velocity relative to major life history milestones. Female geladas finished 88.5% of SR growth by first sexual swelling, and 97.2% by first reproduction, reaching adult body size by 7.72 years of age. Compared to closely related papionins, gelada females finished more growth by first reproduction, despite producing relatively small, and presumably “cheap,” neonates. Male geladas finished 85.4% of growth at dispersal, and 96.0% at estimated first birth. Contrary to other polygynous primates, males are larger than females because they grow for a longer period of time (not because they grow faster), surpassing females around 6 years of age when female growth slows. Our results demonstrate that parallel lasers are an easy and promising new method that can be used to construct comprehensive life history perspectives that were once out of reach for wild populations. Am. J. Primatol. 78:707–719, 2016. © 2016 Wiley Periodicals, Inc.

    

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2. Pastoralism and Emergent Complex Settlement in the Middle Bronze Age, Azerbaijan: isotopic analyses of mobility strategies in transformation

   https://doi.org/10.1002/ajpa.23956  

   Nugent, Selin E. ( November 2019 , American Journal of Physical Anthropology)

   This article explores the scale and seasonal patterns of mobility at the complex settlement site of Qızqala during the Middle Bronze Age (2400–1,500 BCE). By integrating human bone, teeth, and environmental samples this research tests the hypothesis of the persistent importance of community‐wide seasonal pastoral transhumance during the early formation of complex settlement systems of the South Caucasus.

   This research applies stable oxygen and radiogenic strontium isotope analyses on incremental samples of human tooth enamel, bulk tooth enamel, and bone to resolve mobility patterns. Sequential and bulk sampling techniques elucidate seasonal and residential mobility behaviors. Extensive environmental isotope samples of plant and water were collected through regional survey and establish local and regional isotopic baselines, which are compared to human isotope analysis results.

   Qızqala individuals exhibit low isotopic variability compared to regional contemporaries.⁸⁷Sr/⁸⁶Sr ratios from human remains indicate seasonal and residential isotopic variability within the baseline ranges of local landscapes. δ¹⁸O values display erratic patterns, but correspond to seasonal variability with fluctuations between highland and lowland altitudinal zone baseline values.

   Results suggest that isotopic analysis of multiple elements and sequential enamel samples offers finer resolution on the complexities of human mobility strategies and elucidate the daily lives of often overlooked mobile populations. Higher resolution of individual mobility reveals shared routine behaviors that underscore the importance of diverse social collaborations in forming complex polities in the South Caucasus.

    

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3. Comparing self‐harming intentions underlying eating disordered behaviors and nonsuicidal self‐injury : Replication and extension in adolescents

   https://doi.org/10.1002/eat.24043  

   Kline, Kiki M. ; Jorgensen, Saskia L. ; Lawson, W. Cole ; Ohashi, Yuri‐Grace B. ; Wang, Shirley B. ; Fox, Kathryn R. ( August 2023 , International Journal of Eating Disorders)

   Eating disorder (ED) behaviors are often characterized as indirect forms of self‐harm. However, recent research has found less clear demarcations between direct self‐harming behaviors (e.g., nonsuicidal self‐injury [NSSI], suicidal behaviors) than previously assumed. The aim of this study was to replicate findings of this prior research on adult populations in adolescents with a history of restrictive eating.

   A total of 117 adolescents between ages 12–14 were included in the study. Participants reported the presence and frequency of binge eating, compensatory, restrictive eating, and NSSI. Participants also reported thoughts of and intentions to hurt and kill themselves when engaging in each behavior on average. Thet‐tests and linear effects models were conducted to compare self‐harming thoughts and intentions across behaviors.

   Participants reported at least some intent to hurt themselves physically in the moment and in the long‐term when engaging in all ED behaviors and NSSI, and reported engaging in these behaviors while thinking about suicide. Direct self‐harming knowledge and intentions were most frequently reported with NSSI and longer‐term knowledge and intentions via NSSI and restrictive eating. Additionally, participants reported some suicidal thoughts and intentions across behaviors.

   This study replicates prior research, suggesting that adolescents engage in ED behaviors and NSSI with non‐zero self‐harming and suicidal thoughts and intentions. ED behaviors and NSSI may better be explained on a continuum. Implications include the recommendation of safety planning during ED treatment.

   This study highlights the overlap between eating disorder (ED) behaviors, nonsuicidal self‐injury (NSSI), and suicide. Though clear distinctions typically exist for motives of self‐harming behavior between ED behaviors (i.e., indirect, in the long run) and NSSI (i.e., direct, in the moment), this research suggests that intentions for self‐harming and suicide may exist on a continuum. Clinical ED treatment should consider safety planning as part of routine interventions.

    

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4. The complex trophic anatomy of silver carp, Hypophthalmichthys molitrix , highlighting a novel type of epibranchial organ

   https://doi.org/10.1002/jmor.20891  

   Cohen, Karly Elizabeth ; Hernandez, L. Patricia ( October 2018 , Journal of Morphology)

   Hypophthalmichthys molitrix,silver carp, is an invasive Asian carp that has become increasingly widespread and ecologically destructive within the upper Mississippi River Basin. Its complex trophic anatomy may help explain the apparent efficiency with which they consume phytoplankton, outcompeting native filter feeders. This cypriniform species is characterized by trophic synapomorphies that include a palatal organ, loss of upper pharyngeal jaws, and a hypertrophied lower pharyngeal jaw. However, in silver carp these structures have become greatly modified and diverge from the more basal condition that characterizes species such as goldfish. The trophic apparatus of silver carp is composed of discrete structures that are functionally coupled: filtering plates, paired epibranchial organs (EBO), a modified palatal organ composed of large muscular folds that interdigitate with the filtering plates, and hypertrophied lower pharyngeal jaws and teeth. The filtering plates fill a significant portion of the buccal cavity, especially since the distal parts of these filtering plates make up a key component of the EBOs. EBOs, food aggregating structures found in many teleosts, are thought to have independently evolved at least six times. Ranging in complexity from small slits on the dorsal wall of the pharyngeal cavity to exceedingly intricate spiraling structures, EBOs are morphologically diverse among filter‐feeding fishes. Despite this morphological diversity and broad taxonomic distribution, little is known regarding the functional anatomy of the EBO. Moreover, the EBO in silver carp is distinct from the organs previously described in other species, being created by four independent pharyngeal involutions (instead of the more typical one or two) that form spiral‐shaped pharyngeal tubes surrounded by circumferential muscle. On each side of the head greatly hypertrophied hyomandibulae and opercles are connected to the anterior cartilaginous caps of the bilateral EBOs via enlarged muscles. Given that these fish are pump filter feeders we hypothesize that the opercula may compress and expand the EBOs during pumping causing food to be moved posteriorly toward the pharyngeal jaws.

    

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5. Tooth development and replacement in the Atlantic Cutlassfish, Trichiurus lepturus , with comparisons to other Scombroidei

   https://doi.org/10.1002/jmor.20919  

   Bemis, Katherine E. ; Burke, Samantha M. ; St. John, Carl A. ; Hilton, Eric J. ; Bemis, William E. ( December 2018 , Journal of Morphology)

   Atlantic Cutlassfish,Trichiurus lepturus, have large, barbed, premaxillary and dentary fangs, and sharp dagger‐shaped teeth in their oral jaws. Functional teeth firmly ankylose to the dentigerous bones. We used dry skeletons, histology, SEM, and micro‐CT scanning to study 92 specimens ofT. lepturusfrom the western North Atlantic to describe its dentition and tooth replacement. We identified three modes of intraosseous tooth replacement inT. lepturusdepending on the location of the tooth in the jaw. Mode 1 relates to replacement of premaxillary fangs, in which new tooth germs enter the lingual surface of the premaxilla, develop horizontally, and rotate into position. We suggest that growth of large fangs in the premaxilla is accommodated by this horizontal development. Mode 2 occurs for dentary fangs: new tooth germs enter the labial surface of the dentary, develop vertically, and erupt into position. Mode 3 describes replacement of lateral teeth, in which new tooth germs enter a trench along the crest of the dentigerous bone, develop vertically, and erupt into position. Such distinct modes of tooth replacement in a teleostean species are unknown. We compared modes of replacement inT. lepturusto 20 species of scombroids to explore the phylogenetic distribution of these three replacement modes. Alternate tooth replacement (in which new teeth erupt between two functional teeth), ankylosis, and intraosseous tooth development are plesiomorphic to Bluefish + other Scombroidei. Our study highlights the complexity and variability of intraosseous tooth replacement. Within tooth replacement systems, key variables include sites of formation of tooth germs, points of entry of tooth germs into dentigerous bones, coupling of tooth germ migration and bone erosion, whether teeth develop horizontally or immediately beneath the tooth to be replaced, and how tooth eruption and ankylosis occur. Developmentally different tooth replacement processes can yield remarkably similar dentitions.

    

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