Hasil untuk "Physical anthropology. Somatology"

H. Donnan, T. Wilson

Гусева В.П., Буряк А.Д., Фёдоров А.С. et al.

Введение. Антропологические коллекции из закрытых археологических комплексов представляют собой уникальный источник для реконструкции образа жизни и состояния здоровья населения прошлого методами биоархеологии. Цель исследования: проведение комплексного палеопатологического анализа антропологической коллекции из некрополя г. Вологды (2-я половина XV – 1-я половина XVI в.). Материалы и методы. Антропологический материал происходит из некрополя, изученного в 2022 г. в ходе раскопок по адресу: г. Вологда, ул. Ленинградская, д. 12. Раскоп площадью 166 м² вскрыл 121 погребение, датируемое 2-й половиной XV – 1-й половиной XVI в. Палеопатологическое исследование взрослой группы (N=44) проводилось по стандартным макроскопическим и рентгенологическим методикам; для сравнения частот использовался точный критерий Фишера. Результаты. Выявлены различия в распределении частот патологий по полу. Мужская серия демонстрирует высокий уровень травматизма (67,9%), в рамках которого чаще встречаются переломы ребер (42,9%). У женщин уровень травматизма ниже (33,3%) и ограничен дистальными отделами конечностей. При анализе дегенеративных заболеваний позвоночника выделяется высокая частота узлов Шморля у женщин (80,0%). Статистически значимые различия в частотах встречаемости кариеса между мужчинами (29,2%) и женщинами (55,6%) отсутствуют, хотя и наблюдается тенденция к более высокой распространенности заболевания в женской группе. В обеих группах зафиксированы единичные случаи тяжелых инфекционных и системных заболеваний. Обсуждение. Характер травматизма у мужчин свидетельствует об их высокой вовлечённости в межличностные конфликты. Характер дегенеративных изменений позвоночника позволяет выдвинуть гипотезу о разделении типов деятельности в зависимости от пола. Высокая частота грыж Шморля у женщин, в свою очередь, является яркой особенностью, так как этиология данной патологии комплексна и может быть связана не только с деятельностью, но и с конституциональными и генетическими факторами. У мужчин же наблюдается лишь тенденция к более выраженным проявлениям артроза и остеофитоза, вероятно, связанных с физическими нагрузками и возрастными изменениями. Заключение. Анализ антропологической коллекции из узкодатированного закрытого комплекса г. Вологды позволил реконструировать состояние здоровья населения города в период его становления как важного военно-административного центра. Благодарности. Статья подготовлена в рамках выполнения темы НИР Института археологии Российской академии наук «Древнее и средневековое население Европейской части России в контекстах культурного развития и динамики генетического состава» (НИОКТР № 124050700063-0).

J. M. Bestenlehner, Paul A. Crowther, V. A. Bronner et al.

We aim to determine the physical properties of OB stars from the multi-epoch VLT/FLAMES BLOeM spectroscopic survey of the Small Magellanic Cloud. We apply a pipeline designed to analyse large spectroscopic samples of OB stars to the co-added, initial 9 epochs of the BLOeM survey, utilising grids of synthetic model spectra computed with the stellar atmosphere code FASTWIND. 69 OB stars are excluded from the analysis owing to disk emission or significant contamination by secondaries in SB2 binaries. We determine physical properties of 778 OB stars, including Teff, log g, log L/Lsun and v_e sin i. There appears to be a bimodality in v_e sin i of single O stars, while v_e sin i distributions of OB stars are strikingly different for single (median 78 km/s) and binary (median 200 km/s) systems. Inferred temperatures are broadly in agreement with literature results for stars in common, plus results from a grid-based automization tool for a subset of O and early B stars, although uncertainties are larger for surface gravities. Rotational velocities are broadly in line with an independent tool applied to the same subset. We recover the anticipated lower mass cutoff at 8 Msun from the survey design using a Bayesian inference method coupled with SMC metallicity evolutionary models, with median masses of 12.6 Msun (19.8 Msun) for B-type (O-type) stars. Spectroscopic masses exceed evolutionary masses, albeit with large uncertainties in surface gravities. We also provide an updated catalogue of O stars in the SMC since half of the 159 BLOeM O stars are newly classified as O-type stars.

Akshay Govind Srinivasan, Vikas Dwivedi, Balaji Srinivasan

Partial differential equation (PDE) solvers are fundamental to engineering simulation. Classical mesh-based approaches (finite difference/volume/element) are fast and accurate on high-quality meshes but struggle with higher-order operators and complex, hard-to-mesh geometries. Recently developed physics-informed neural networks (PINNs) and their variants are mesh-free and flexible, yet compute-intensive and often less accurate. This paper systematically benchmarks RBF-PIELM, a rapid PINN variant-an extreme learning machine with radial-basis activations-for higher-order PDEs. RBF-PIELM replaces PINNs' time-consuming gradient descent with a single-shot least-squares solve. We test RBF-PIELM on the fourth-order biharmonic equation using two benchmarks: lid-driven cavity flow (streamfunction formulation) and a manufactured oscillatory solution. Our results show up to $(350\times)$ faster training than PINNs and over $(10\times)$ fewer parameters for comparable solution accuracy. Despite surpassing PINNs, RBF-PIELM still lags mature mesh-based solvers and its accuracy degrades on highly oscillatory solutions, highlighting remaining challenges for practical deployment.

Dongyang Yan, Alexander S. Shalin, Yongxing Wang et al.

Higher-order exceptional points (EPs) in optical structures enable ultra-sensitive responses to perturbations. However, previous investigations on higher-order EPs have predominantly focused on coupled systems, leaving their fundamental physics in open scattering systems largely unexplored. Here, we harness wave interference to realize higher-order EPs in non-Hermitian zero-index materials connected to multiple open channels. Specifically, we show that a three-channel model can give rise to three interesting types of third-order EPs: lasing EP, reflecting EP, and absorbing EP. Notably, near the third-order absorbing EP, we show ultrasensitivity -- a drastic change in output power in response to perturbations at the operating frequency -- in a purely lossy system. These findings pave the way for achieving higher-order and even arbitrary-order EPs in open scattering systems, offering significant potential for advanced sensing applications.

Peipei Zhang, Yunzhi Yao, Zhengkun Hu et al.

A new genus and species of fossil harpactorin (Hemiptera: Reduviidae), Trispongiosus hui Zhang, Yao, & Liu gen. et sp. nov., is described from Miocene Dominican amber, representing the third fossil record of Harpactorinae. The new species is remarkable for exhibiting fossula spongiosa on all three pairs of legs, which is not only the first report in Harpactorinae but also rare within Reduviidae. This structure is considered to be related to the locomotor capabilities of assassin bugs, potentially enhancing their attachment and agility in navigating complex surfaces and vegetation. Furthermore, the present study suggests that fossula spongiosa exhibits remarkable plasticity within Reduviidae by integrating fossil and extant perspective.

Jan van der Made, Ignacio A. Lazagabaster, Paula García-Medrano et al.

During the Pleistocene, the successive ice ages prompted the southward expansion of the “Mammoth Steppe” ecosystem, a prevalent habitat that supported species adapted to cold environments such as the mammoth, woolly rhinoceros, and reindeer. Previously, the earliest evidence for such cold-adapted species in the Iberian Peninsula dated back to Marine Isotope Stage 6 (MIS 6, ~191–123 ka). This paper reports the discovery of a reindeer (<i>Rangifer</i>) tooth from Unit GIII of the Galería site at the Atapuerca-Trinchera site complex, dated to MIS 8 (~300–243 ka). This find is significant as it represents not only the oldest evidence of glacial fauna in the Iberian Peninsula but also the southernmost occurrence of reindeer in Europe of this age. The presence of <i>Rangifer</i> at this latitude (42°21′ N) during MIS 8 suggests that the glacial conditions affected the Iberian fauna earlier and with greater intensity than previously understood. Over the subsequent climatic cycles, cold-adapted species spread further south, reaching Madrid (40°20′) during the penultimate glacial period and the province of Granada (37°01′) during the last glacial maximum. The coexistence of human fossils and lithic artefacts within Units GII and GIII at Galería indicates that early humans also inhabited these glacial environments at Atapuerca. This study elaborates on the morphological and archaeological significance of the reindeer fossil, emphasizing its role in understanding the biogeographical patterns of glacial fauna and the adaptability of Middle Pleistocene human populations.

Hridoy Debnath, Pavel Fileviez Perez, Kevin Gonzalez-Quesada

We discuss a simple theory for physics beyond the Standard Model where a Majorana dark matter is predicted from anomaly cancellation. We discuss in detail the minimal theory where the baryon number is a local symmetry spontaneously broken at the low scale. The correlation between the cosmological constraints on the dark matter relic density, the direct detection and collider bounds is investigated. We discuss in great detail the gamma lines from dark matter annihilation showing the possibility to test these predictions in the near future at gamma-ray telescopes such as CTA. We investigate all processes contributing to the total photon flux from dark matter annihilation and point out the unique features that can be used to test this theory for dark matter.

James A. Monro, Andrew M. Kingston, David M. Paganin

Ghost projection is the reversed process of computational classical ghost imaging that allows any desired image to be synthesized using a linear combination of illuminating patterns. Typically, physical attenuating masks are used to produce these illuminating patterns. A mask-free alternative form of ghost projection is explored here, where the illuminations are a set of caustic-laden diffraction patterns known as diffraction catastrophes. These are generated by focusing a coherent beam with spatially modulated phase having random Zernike-polynomial aberrations. We demonstrate, via simulation, that a suitable linear combination of such random focal-field intensity patterns can be used as a basis to synthesize arbitrary images. In our proof-of-concept ghost-projection synthesis, the positive weighting coefficients in the decomposition are proportional to exposure times for each focal-field diffraction catastrophe. Potential applications include dynamic on-demand beam shaping of focused fields, aberration correction and lithography.

Sergei V. Kalinin, Eugene A. Eliseev, Anna N. Morozovska

The fundamental aspect of physics of ferroelectric materials is the screening of uncompensated bound charges by the dissociative adsorption of ionic charges from the environment. The adsorption of ions can be especially strong when the ferroelectric undergoes the temperature-induced transition from the paraelectric phase to the ferroelectric state. Here we demonstrate that the adsorption of ions and free radicals by the polar surface of ferroelectric nanoparticles can be very efficient in aqueous solutions due to the strong ferro-ionic coupling in the nanoparticles. Obtained results can be useful for the elaboration of alternative methods and tools for adsorption of the cations (Li+, K+, Na+, etc.), anions (Cl-, Br-, J-), and/or free radicals (CO-, NH4+, etc.) from aqueous solutions by the lead-free uniaxial ferroelectric nanoparticles. The results may become an alternative way for the environment-friendly laboratory-scale purification of different aqueous solutions from ionic contamination using controllable cyclic temperature variations.

Heinz Furrer

Abstract There is a long history of palaeontological excavations at Monte San Giorgio (Switzerland) and the adjoining Monte Pravello—Monte Orsa (Italy), aimed at finding well-preserved skeletons of Middle Triassic vertebrates. The first fossils were discovered in the mid-Nineteenth Century during mining of black shales (scisti bituminosi) near Besano, Italy, with further finds in the early Twentieth Century through industrial-scale mining. Studies of the material generated international interest and prompted formal palaeontological excavations on both sides of the border. The earliest excavations took place in 1863 and 1878, with the most extensive between 1924 and 1968. Systematic excavations have continued up to the present day, focusing on six distinct fossiliferous horizons: the Besano Formation and the overlying Meride Limestone with the Cava inferiore, Cava superiore, Cassina, Sceltrich and Kalkschieferzone beds. All these have provided material for study and display, with Monte San Giorgio itself recently designated a UNESCO World Heritage Site. The workers and organisations involved, locations excavated and material recovered are described herein.

Yuya Haraguchi, Daisuke Nishio-Hamane, Hiroko Aruga Katori

In spinel-type nickelate NiRh$_2$O$_4$, magnetic ordering is observed upon the sample synthesized via kinetically controlled low-temperature solid-state metathesis, as opposed to previously-reported samples obtained through conventional solid-state reaction. Our findings are based on a combination of bulk susceptibility and specific heat measurements that disclose a N$é$el transition temperature of $T_N$ = 45 K in this material, which might feature spin-orbit entanglement in the tetragonally-coordinated $d^8$ Mott insulators. The emergence of magnetic ordering upon alteration of the synthesis route indicates that the suppression of magnetic ordering in the previous sample was rooted in the cation-mixing assisted by the entropy gain that results from high-temperature reactions. Furthermore, the $J_{\rm eff}$ = 0 physics, instead of solely the spin-only $S = 1$, describes the observed enhancement of effective magnetic moment well. Overseeing all observations and speculations, we propose that the possible mechanism responsible for the emergent magnetic orderings in NiRh$_2$O$_4$ is the condensation of $J_{\rm eff}$ = 0 exciton, driven by the interplay of the tetragonal crystal field and superexchange interactions.

Jingxu Bai, Yuechun Jiao, Rong Song et al.

Long-range $(n+2)D_{5/2} \, nF_J$ Rydberg macro-dimers are observed in an ultracold cesium Rydberg gas for $39\leq n\leq48$. Strong dipolar "flip" ($\langle D_{5/2} F_{5/2} \vert \hat{V}_{dd} \vert F_{5/2} D_{5/2} \rangle$, $\langle D_{5/2} F_{7/2} \vert \hat{V}_{dd} \vert F_{7/2} D_{5/2} \rangle$) and "cross" ($\langle D_{5/2} F_{7/2} \vert \hat{V}_{dd} \vert F_{5/2} D_{5/2} \rangle$) couplings lead to bound, fine-structure-mixed $(n+2)D_{5/2}nF_J$ macro-dimers at energies between the $F_J$ fine-structure levels. The $DF$ macro-dimers are measured by microwave photo-association from optically prepared $[(n+2)D_{5/2}]_2$ Rydberg pair states. Calculated adiabatic potential curves are used to elucidate the underlying physics and to model the $DF$ macro-dimer spectra, with good overall agreement. Microwave photo-association allows Franck-Condon tuning, which we have studied by varying the detuning of a Rydberg-atom excitation laser. Further, in Stark spectroscopy we have measured molecular DC electric polarizabilities that are considerably larger than those of the atomic states. The large molecular polarizabilities may be caused by high-$\ell$ mixing. The observed linewidths of the Stark-shifted molecular lines provide initial evidence for intra-molecular induced-dipole-dipole interaction.

Gabriele Gattiglia, Eleonora Rattighieri, Eleonora Clò et al.

In central Italy, the Charterhouse of Calci hosts the Natural History Museum of the University of Pisa. This monumental monastery was founded in 1366 by Carthusian monks. The Charterhouse has experienced various transformations over the centuries, until its abandonment in the 1970s. Since 2018, interdisciplinary archaeological research focused on the monks’ gardens (and particularly: the Prior’s, the Apothecary’s, and the Master’s garden) and the green spaces outside the cloister walls, consisting of courtyards and orchards, to determine the individual (gardens) and collective (green spaces and surrounding woods) practices adopted by Carthusians. Palynology and archaeobotany have allowed to reconstruct the plant biodiversity, with flowers and ornamental, aromatic, and medicinal herbs that grew in the gardens, as well as the management of local hilly woods and agricultural practices, including the cultivation of fruit trees, such as chestnut, olive tree, almond tree, and grapevine. Our research has been based on a solid theoretical approach, interpreting archaeological and archaeobotanical data in relation to the intricate network of human and non-human connections. Gardens are seen as a co-creation made together by human and non-human agencies, and their diachronic transformation is read as an expression of personalities of the monks, feelings, and connections with nature and divinity.

Leonardo Kerber

Abstract Here I reviewed the Pleistocene caviomorphs collected by Santiago Roth (collection from Catalog No. 5) and housed at the paleontological collection of the Paläontologisches Institut und Museum, Universität Zürich, Zurich (Switzerland). The fossils were found in Pleistocene strata from Buenos Aires and Santa Fé provinces (Argentina) during the late nineteenth century. The material includes craniomandibular remains assigned to Lagostomus maximus (Chinchilloidea: Chinchillidae), craniomandibular and postcranial (thoracic and sacral vertebra, left scapula, left femur, and right tibia) bones identified as Dolichotis sp. (Cavioidea: Caviidae), and a fragmented hemimandible and isolated tooth of Myocastor sp. (Octodontoidea: Echimyidae). Other rodent specimens from this collection (Ctenomys sp. and Cavia sp.) are possibly sub-recent materials.

Tamás Zsolt Vári, Sándor Gulyás, Pál Sümegi

Lake Kolon (Hungary), situated in the middle of the Turjánvidék area between the saline lakes of the Danube valley and the Homokhátság, is one of the most significant natural aquatic habitats in the Danube–Tisza Interfluve region. The central question of this study is how the lake changed, and how environmental factors and human activities have influenced these paleoenvironmental changes in Lake Kolon. A multiproxy analysis of a core sequence (loss on ignition, grain size, magnetic susceptibility, and geochemistry) provided crucial insights. Notably, correlations are observed in the following relationships: (1) clay, organic matter, and elements derived from organic sources, such as Na, K, and Zn; (2) MS, sand, inorganic matter, and elements originating from inorganic sources, such as Fe, Al, Ti, Na, K, and P; and (3) carbonate content and elements originating from carbonate sources, such as Ca and Mg. The lake’s paleoenvironment underwent significant changes in the past 27,000 years. Late-Pleistocene wind-blown sand provided the bottom for an oligotrophic lake (17,700 BP), followed by a calcareous mesotrophic Chara-lake phase (13,800 BP). Peat accumulation, along with the eutrophic lake phase, began at the Pleistocene–Holocene boundary around 11,700 BP. From 10,300 BP, with the emergence of an extended peatland phase, the percentage of organic matter (peat) increased significantly. Anthropogenic changes occurred from around 9000–8000 BP due to the different emerging cultures in the Carpathian basin, and from 942–579 BP due to the Hungarian settlements and activity nearby, respectively.

L. Menéndez, Kathleen S. Paul, C. de la Fuente et al.

The timing and mode(s) of the initial human occupation of the Americas are among the most discussed topics in archaeology and biological anthropology, with hundreds of articles published in the last decades dedicated to the topic (for some comprehensive reviews, see References 1–3). Researchers have contributed to the debates through a vast range of disciplines, methodological and theoretical approaches, ranging from traditional archeological and bioarchaeological methods, to climate simulations and ancient DNA analyses. And yet, despite recent advances in the study of the biological variation and prehistoric expansions of populations into and within the Americas, there is still little consensus about key questions including the time and modes of human dispersion across the continents. This brings up a crucial question: why are we unable to find a consensus about the processes behind the initial settlements of the Americas? There are certainly multiple factors contributing to our inability to build reliable interpretations on this topic. Some of them are common to all endeavors to reconstruct and study past human societies across the planet, and some are unique to the history of research in the Americas. As a result, it is not uncommon to find significant reevaluations of current models and hypotheses, either through new findings and new methodological innovations (see, e.g., the most recent findings of early footprints in New Mexico), by the reanalysis of radiocarbon data accumulated over decades of research, or due to new theoretical framings of available data (see Reference 6 as a good example). While these constant reevaluations of the origins of early inhabitants of the Americas are related to all aspects of this process (e.g., chronology, cultural diversity, adaptation, and biological diversity), here we focus on recent discussions about the origins of Native American biological diversity, which by itself has been the focus of a vast and prolific literature. The study of biological diversity among early Native Americans has progressed at a remarkably fast pace in recent decades, and researchers new to this topic will probably find the process of reviewing the body of specialized literature daunting. Recent studies have drawn upon a wealth of different modern sources of information, including molecular (Y-chromosome, mitochondrial-DNA, autosomal markers), morphological (cranial, dental, and postcranial), and cultural (linguistic, lithic technology, and physical activity) data. The rapid incorporation of cutting-edge methods in the last decades has brought to the research of the early peopling and diversity of the Americas the sequencing of whole ancient genomes, registering high-quality morphological data with 3D surface and CT-scanners, performing digital reconstructions of fragmented anatomical structures, as well as accessing and sharing a large amount of data thanks to Big Data and Open Science initiatives. However, while these methodologically advanced studies are bringing new sources of information to the discussion, they have also siloed most of the discussions within the confines of specialized subdisciplines, limiting the dialog between researchers from different backgrounds. Indeed, there are only a handful of projects that have taken advantage of multidisciplinary perspectives. Consequently, recent discussions about the biological variation and migratory patterns of early Americans are mostly restricted to (re)interpretations of a few former models and rarely integrate discussions derived from analyzing different kinds of evidence. Evidently, this limitation can be largely explained as the result of the progressive degree of academic specialization required to handle each data type, as well as the substantial expertise and financial support needed to carry them out. Because of this natural tendency of specialization, we have reached a moment in which it is crucial to promote more dialog among research groups and stakeholders and integrate frameworks combining cultural, genetic, and morphological data to study migratory patterns and biological diversity among Native Americans. With this shared goal in mind, the authors participated in an interdisciplinary symposium in the context of the 90th Annual meeting of the American Association of Physical (now Biological) Anthropologists (Figure 1). The symposium focused on debating how different kinds of evidence contribute to discuss various aspects of the origin and expansions of human populations across the Americas and included experts representing diverse career stages, gender, ethnicity, as well as different countries of origin. The diverse panel of specialists enriched the discussions by contributing their own perspectives from both South, Central, and North American backgrounds. The lessons learned from discussions held at the symposium, and the fact that all participants share the feeling that more interdisciplinary dialog is needed, prompted us to write this overview article. We had the opportunity to share ideas with specialists working with cranial morphology, dental metrics and non-metrics, linguistics, and DNA from prehistoric and/or extant populations, as they discussed their current work on ancient expansions and biocultural diversity in the Americas. While these disciplines cover only a fraction of research topics and disciplines focused on the human occupation of the Americas, the work presented highlights a series Received: 10 December 2021 Revised: 20 December 2021 Accepted: 28 December 2021

Yue Sun, Tao Shi, Zhiyong Liu et al.

Exploring non-Hermitian phenomenology is an exciting frontier of modern physics. However, the demonstration of a non-Hermitian phenomenon that is quantum in nature has remained elusive. Here, we predict quantum non-Hermitian phenomena: the fractional quantum Zeno (FQZ) effect and FQZ-induced photon antibunching. We consider a quantum optics platform with reservoir engineering, where nonlinear emitters are coupled to a bath of decaying bosonic modes whose own decay rates form band structures. By engineering the dissipation band, the spontaneous emission of emitters can be suppressed by strong dissipation through an algebraic scaling with fractional exponents - the FQZ effect. This fractional scaling originates uniquely from the divergent dissipative density of states near the dissipation band edge, different from the traditional closed-bath context. We find FQZ-induced strong photon antibunching in the steady state of a driven emitter even for weak nonlinearities. Remarkably, we identify that the sub-Poissonian quantum statistics of photons, which has no classical analogs, stems here from the key role of non-Hermiticity. Our setup is experimentally feasible with the techniques used to design lattice models with dissipative couplings.

Zulma Gasparini, Leonardo Salgado, Julia B. Desojo

Los inicios de la paleoherpetología argentina se remontan a los orígenes de la ciencia en el país. En sus primeras décadas fueron clave el Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” en la Ciudad Autónoma de Buenos Aires y el Museo de La Plata en la misma provincia. A estos dos, se sumaron un importante número de instituciones científicas en diferentes provincias, como museos municipales y provinciales, universidades nacionales o nuevos institutos de investigación del CONICET, que se desarrollaron a partir del incremento de nuevas líneas de estudio y la formación de colecciones. Asimismo, las instituciones se fortalecieron con la incorporación de jóvenes paleoherpetólogos de esas mismas provincias o de otras partes del país y del extranjero. En la actualidad, un número importante de investigadores y técnicos, entre ellos ilustradores y paleoartistas, se dedican al desarrollo de la disciplina, contribuyendo no solo al incremento del conocimiento paleoherpetológico, tanto científico como divulgativo, sino también al mantenimiento de los parques naturales y la promoción de turismo.

DEBRA L. HANNEMAN , DONALD LOFGREN , STEPHEN T. HASIOTIS et al.

Sanidine 40Ar/39Ar ages of lapilli tuffs and the mammalian fauna of Pipestone Springs strata provide a high-resolution chronostratigraphy for upper Eocene (Priabonian) rock units in southwestern Montana. Two felsic lapilli tuffs with weighted-mean 40Ar/39Ar single crystal sanidine ages of 37.50±0.02 Ma and 36.00±0.20 Ma both fall within the Priabonian, late Eocene. These tuffs occur within the basal to upper part of the 55 m of exposed Pipestone Springs strata. The uppermost 15 m yield a diverse and abundant assemblage of mostly small-bodied middle Chadronian (Priabonian, late Eocene) mammals. The older lapilli tuff is an ashfall tuff, whereas the younger lapilli tuff exhibits minor aeolian reworking. The new 40Ar/39Ar age constraints significantly increase the age range of Pipestone Springs strata to include uppermost Duchesnean–lowermost Chadronian (Priabonian, upper Eocene) deposits in addition to its well-known middle Chadronian vertebrate assemblage. These new 40Ar/39Ar ages combined with its mammalian fauna further support Pipestone Springs strata as age-correlative to the Flagstaff Rim section in central Wyoming, and provide a basis for better determining late Eocene mammalian paleogeography and regional paleolandscapes in the United States Rocky Mountain to Great Plains areas. Loessites intercalated with paleosols dominate Pipestone Springs deposits. The recognition of loessites comprising these strata is a new depositional interpretation of Pipestone Springs strata, making these loessites some of the oldest known aeolian Eocene strata in the Great Plains–Rocky Mountains region. Pipestone Springs paleosols developed on lapilli tuffs are vertisols. Alfisols and inceptisols, developed from a parent material of volcanic glass mixed with non-volcanic grains, are the remaining paleosols within the loessite strata. Additionally, a new and important discovery in this project is the recognition that all paleosols are extensively bioturbated, containing trace fossils similar to Rebuffoichnus and newly identified trace fossils resembling Feoichnus, Eatonichnus, Fictovichnus, and Coprinisphaera.