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1. IDENTIFYING LOCAL AND NON-LOCAL POTTERY IN THREE TOMBS AT UXBENKÁ, TOLEDO DISTRICT: RESULTS OF THIN SECTION ANALYSIS

   Jordan, Jillian ; Prufer, Keith ( January 2020 , Research reports in Belizean archaeology)

   Southern Belize has received less archaeological attention than other areas due in large part to its remote location. However, the difficulty in accessing the area in recent times does not necessarily equate to isolation for the Classic Period Maya who lived in what is now the Toledo District. This paper discusses petrographic data collected on ceramic vessels recovered from burial contexts at Uxbenká, Belize. The partial and reconstructed whole vessels from these primary contexts include locally produced vessels that are stylistically and technologically unique to the southern Belize region and vessels produced elsewhere. We use these data to evaluate how local Uxbenká potters produced ceramic vessels for local consumption and to identify long-distance interaction networks between Uxbenká and other regions of the Maya Lowlands. Our data indicate that most of the pottery at Uxbenká was produced locally. However, elite tombs often include both local and non-local vessels. The elites of Uxbenká engaged in interaction with people living much farther afield in regions like the Belize River Valley and possibly Guatemala. 

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2. Genetic structuring and species boundaries in the Atlantic stony coral Favia (Scleractinia, Faviidae)

   https://doi.org/10.1111/zsc.12652  

   Adam, Carolina de Lima ; Toonen, Robert J. ; Carlon, David B. ; Zilberberg, Carla ; Barbeitos, Marcos Soares ( January 2024 , Zoologica Scripta)

   Scleractinian corals are the main modern builders of coral reefs, which are major hot spots of marine biodiversity. Southern Atlantic reef corals are understudied compared to their Caribbean and Indo‐Pacific counterparts and many hypotheses about their population dynamics demand further testing. We employed thousands of single nucleotide polymorphisms (SNPs) recovered via ezRAD to characterize genetic population structuring and species boundaries in the amphi‐Atlantic hard coral genusFavia. Coalescent‐based species delimitation (BFD* – Bayes Factor Delimitation) recoveredF. fragumandF. gravidaas separate species. Although our results agree with depth‐related genetic structuring inF. fragum, they did not support incipient speciation of the ‘tall’ and ‘short’ morphotypes. The preferred scenario also revealed a split between two main lineages ofF. gravida, one from Ascension Island and the other from Brazil. The Brazilian lineage is further divided into a species that occurs throughout the Northeastern coast and another that ranges from the Abrolhos Archipelago to the state of Espírito Santo. BFD* scenarios were corroborated by analyses of SNP matrices with varying levels of missing data and by a speciation‐based delimitation approach (DELINEATE). Our results challenge current notions about Atlantic reef corals because they uncovered surprising genetic diversity inFaviaand rejected the long‐standing hypothesis that Abrolhos Archipelago may have served as a Pleistocenic refuge during the last glaciations.

    

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3. Varieties of the highly dispersible and hypervariable tree, Metrosideros polymorpha , differ in response to mechanical stress and light across a sharp ecotone

   https://doi.org/10.1002/ajb2.1331  

   Ekar, Jill M. ; Price, Donald K. ; Johnson, Melissa A. ; Stacy, Elizabeth A. ( July 2019 , American Journal of Botany)

   The drivers of isolation between sympatric populations of long‐lived and highly dispersible conspecific plants are not well understood. In the Hawaiian Islands, the landscape‐dominant tree,Metrosideros polymorpha, displays extraordinary phenotypic differences among sympatric varieties despite high dispersibility of its pollen and seeds, thereby presenting a unique opportunity to investigate how disruptive selection alone can maintain incipient forms. StenophyllousM. polymorphavar.newelliiis a recently evolved tree endemic to the waterways of eastern Hawai'i Island that shows striking neutral genetic differentiation from its ancestor, wet‐forestM. polymorphavar.glaberrima, despite sympatry of these forms. We looked for evidence for, and drivers of, differential local adaptation of these varieties across the range ofM. polymorphavar.newellii.

   For paired populations of these varieties, we compared seedling performance under contrasting light conditions and a strong water current characteristic of the riparian zone. We also conducted a reciprocal transplant experiment and contrasted adult leaf anatomy.

   Results suggest that the riparian zone is harsh and that selection involving the mechanical stress of rushing water, and secondarily, light, led to significant reciprocal immigrant inviability in adjacent forest and riparian environments. The strongest adaptive divergence between varieties was seen in leaves and seedlings from the site with the sharpest ecotone, coincident with the strongest genetic isolation ofM. polymorphavar.newelliiobserved previously.

   These findings suggest that disruptive selection across a sharp ecotone contributes to the maintenance of an incipient riparian ecotype from within a continuous population of a long‐lived and highly dispersible tree species.

    

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4. Ceramic exchange networks in the south‐central Tuxtla Mountains, southern Veracruz, Mexico

   https://doi.org/10.1002/gea.21836  

   Venter, Marcie L. ; Pierce, Daniel ; Glascock, Michael D. ( January 2021 , Geoarchaeology)

   Our study situates the classic period center Matacanela, located in southern Veracruz, Mexico, within the context of shifting regional political‐economic systems. Specifically, we assess the potential for utilizing neutron activation analysis (NAA) of pottery in the study of changing interactions through a focus on three ceramic wares: Coarse Orange, Fine Orange, and Coarse Brown. NAA identified four compositional groups, suggesting that Matacanela selectively utilized ceramics from a variety of sources, but the center's inhabitants overwhelming used ceramics that were only occasionally exploited by their contemporaries in the nearby Catemaco and Tepango valleys. Instead, the center's primary ceramic exchange partners were in the southern Tuxtlas foothills. This divergent pattern of ceramic exchange parallels earlier obsidian exploitation differences that revealed participation in the networks of the western Tuxtla uplands as well as the southern foothills and centers within eastern Olman. The findings of this study contribute to (1) the geological characterization of ceramic resources used by ancient Gulf lowland societies, (2) to the comparative ceramic database in a region that was an important nexus for diverse cultural traditions spanning Mesoamerican prehistory, and (3) the refinement of our knowledge relevant to the divergent strategies employed by groups.

    

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5. Deep slab collision during Miocene subduction causes uplift along crustal-scale reverse faults in Fiordland, New Zealand

   Keith Klepeis, Laura Webb ( July 2019 , GSA today)

   A new multidisciplinary project in southwest New Zealand that combines geological and geophysical data shows how and why deep lithospheric displacements were transferred vertically through the upper plate of an incipient ocean-continent subduction zone. A key discovery includes two zones of steep, downward-curving reverse faults that uplifted and imbricated large slices of Cretaceous lower, middle, and upper crust in the Late Miocene. Geochemical and structural analyses combined with 40Ar/39Ar geochronology and published images from seismic tomography suggest that the reverse faults formed at 8–7 Ma as a consequence of a deep (~100 km) collision between subducting oceanic lithosphere and previously subducted material. This collision localized shortening and reactivated two crustal-scale shear zones from the upper mantle to the Earth’s surface. The event, which is summarized in a new lithospheric-scale profile, is helping us answer some long-standing questions about the origin of Fiordland’s unique lower-crustal exposures and what they tell us about how inherited structures can transfer motion vertically through the lithosphere as subduction initiates. 

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