Hasil untuk "Fossil man. Human paleontology"

WANG Xiao-Ming, SUN Lu, LI Lu, LI Qiang, QIU Zhu-Ding, Zhijie Jack TSENG

In addition to its well-known fossils, the Upper Miocene Baogeda Ula Formation is coupled with multiple basaltic lava flows, creating an ideal setting for studying its depositional history, geochronology, and associated vertebrate fossils. This paper, in honor of Prof. Qiu Zhanxiang for his widely admired emphasis on the geological contexts of vertebrate fossils, attempts to synthesize known contact relationships, existing K-Ar dates, and capping basalt elevations to reframe our concept of the lithostratigraphy, magnetostratigraphy, and lateral distribution of the Baogeda Ula Formation. Within this new framework, the Baogeda Ula Formation is defined by unconformable contact with the underlying Tunggur Formation at the lower boundary and a capping basalt at the upper boundary. In many sections, two or three layers of basalts are interbedded within sedimentary strata, with the capping basalts typically belonging to the top two basalts. The newly defined Baogeda Ula Formation includes a lower member as exemplified by Halajin Hushu section and Ulan Hushuyin Nur section, and an upper member at Baogeda Ula section. This expanded concept of the Baogeda Ula Formation includes two major faunas, i.e., the Bahean Halajin Hushu Fauna and Baodean Baogeda Ula Fauna, both falling within the Upper Miocene. We also describe rare fossil skunks (Promephitis) found in recent years that support the age assessments presented herein.

Kiyosu Maeda, William P. McCarthy, Ching-Yi Tsai et al.

A quintessential feature of human intelligence is the ability to create ad hoc conventions over time to achieve shared goals efficiently. We investigate how communication strategies evolve through repeated collaboration as people coordinate on shared procedural abstractions. To this end, we conducted an online unimodal study (n = 98) using natural language to probe abstraction hierarchies. In a follow-up lab study (n = 40), we examined how multimodal communication (speech and gestures) changed during physical collaboration. Pairs used augmented reality to isolate their partner's hand and voice; one participant viewed a 3D virtual tower and sent instructions to the other, who built the physical tower. Participants became faster and more accurate by establishing linguistic and gestural abstractions and using cross-modal redundancy to emphasize key changes from previous interactions. Based on these findings, we extend probabilistic models of convention formation to multimodal settings, capturing shifts in modality preferences. Our findings and model provide building blocks for designing convention-aware intelligent agents situated in the physical world.

Thomas Wesener, Peter T. Rühr

Abstract Micro computed tomography (µCT) scans allow a 3D reconstruction of characters otherwise hidden in fossil amber specimens. In this study we reveal the male copulatory legs (gonopods) retracted into the body, and other important morphological characters, for a fossil Juliformia millipede. Characters of the male gonopods are essential for the classification of numerous recent millipede groups. This made it previously almost impossible to correctly assign fossil millipedes to a recent taxon, especially in the Juliformia, where the gonopods are often retracted into the body. The millipede specimen analyzed here is preserved in Myanmar amber dating back to the Cretaceous, 98 MYA (± 0.63 MY). Gonopod and mouthpart characters identify the millipede as a member of the order Spirostreptida, family Cambalopsidae, the first known fossil of one of the most diverse extant SE Asians millipede groups. While the gonopods show similarities to the extant genera Hypocambala Silvestri, 1897, Plusioglyphiulus Silvestri, 1923 and Glyphiulus Gervais, 1847, the presence of neither carinate body rings, nor longitudinally striate metazona, nor a flattened leg pair 2, absence of both an enlarged collum and an enlarged leg pair 2 allows us to describe it as a new genus and species, Laeviglyphiulus patrickmuelleri n. gen., n. sp.

LI Mao-Kun, CUI Xin-Dong, ZHU Min, QIAO Tuo

Here we report a left cheek plate of Psarolepis, a postparietal shield of Youngolepis, a skull of Diabolepis, and a scale of Styloichthys from the Lianhuashan and Nahkaoling formations (Lochkovian, Lower Devonian) of Nanning, Guangxi. This marks the first report of Diabolepis and Styloichthys beside Qujing, Yunnan, and the latest occurrence of Psarolepis to date. The fossil community displays significant similarities to the Xujiachong Assemblage, and provides new data for the Lower Devonian stratigraphic correlation between southwestern China and northern Vietnam. Given the latest dating constraint based on the conodont evidence, we regard that the Xujiachong Assemblage has a much longer range than previously supposed, extending from the latest Lochkovian to the end of Pragian. We propose that the transition of the Nahkaoling and Lianhuashan formations in Nanning might correspond to the Guijiatun Formation in Qujing. The relatively large size of fish individuals from Guangxi is probably attributed to the increase in the oxygen content of the ocean.

Gregory M Ellison, Liang Liu

Estimating divergence times from molecular sequence data is central to reconstructing the evolutionary history of lineages. Although Bayesian relaxed-clock methods provide a principled framework for incorporating fossil information, their dependence on repeated evaluations of the full phylogenetic likelihood makes them computationally demanding for large genomic datasets. Furthermore, because disagreements in divergence-time estimates often arise from uncertainty or error in fossil placement and prior specification, there is a need for methods that are both computationally efficient and robust to fossil-calibration uncertainty. In this study, we introduce fast and accurate alternatives based on the phylogenetic pairwise composite likelihood, presenting two adjusted pairwise likelihood (APW) formulations that employ asymptotic moment-matching weights to better approximate the behavior of the full likelihood within a Bayesian MCMC framework. Extensive simulations across diverse fossil-calibration scenarios show that APW methods produce node-age estimates comparable to those obtained from the full likelihood while offering greater robustness to fossil misplacement and prior misspecification, due to the reduced sensitivity of composite likelihoods to local calibration errors. Applied to a genome-scale dataset of modern birds, APW methods recover divergence time patterns consistent with recent studies, while reducing computational cost by more than an order of magnitude. Overall, our results demonstrate that adjusted pairwise likelihoods provide a calibration-robust and computationally efficient framework for Bayesian node dating, especially suited for large phylogenomic datasets and analyses in which fossil priors may be uncertain or imperfectly placed.

Caio C. G. Ribeiro, Douglas G. Macharet

The increasing presence of robots in human environments requires them to exhibit socially appropriate behavior, adhering to social norms. A critical aspect in this context is the concept of personal space, a psychological boundary around an individual that influences their comfort based on proximity. This concept extends to human-robot interaction, where robots must respect personal space to avoid causing discomfort. While much research has focused on modeling personal space in two dimensions, almost none have considered the vertical dimension. In this work, we propose a novel three-dimensional personal space model that integrates both height (introducing a discomfort function along the Z-axis) and horizontal proximity (via a classic XY-plane formulation) to quantify discomfort. To the best of our knowledge, this is the first work to compute discomfort in 3D space at any robot component's position, considering the person's configuration and height.

Henry Peng Zou, Wei-Chieh Huang, Yaozu Wu et al.

Recent advances in large language models (LLMs) have sparked growing interest in building fully autonomous agents. However, fully autonomous LLM-based agents still face significant challenges, including limited reliability due to hallucinations, difficulty in handling complex tasks, and substantial safety and ethical risks, all of which limit their feasibility and trustworthiness in real-world applications. To overcome these limitations, LLM-based human-agent systems (LLM-HAS) incorporate human-provided information, feedback, or control into the agent system to enhance system performance, reliability and safety. These human-agent collaboration systems enable humans and LLM-based agents to collaborate effectively by leveraging their complementary strengths. This paper provides the first comprehensive and structured survey of LLM-HAS. It clarifies fundamental concepts, systematically presents core components shaping these systems, including environment & profiling, human feedback, interaction types, orchestration and communication, explores emerging applications, and discusses unique challenges and opportunities arising from human-AI collaboration. By consolidating current knowledge and offering a structured overview, we aim to foster further research and innovation in this rapidly evolving interdisciplinary field. Paper lists and resources are available at https://github.com/HenryPengZou/Awesome-Human-Agent-Collaboration-Interaction-Systems.

A. Bushi, A. Botteon, D. Dallacasa et al.

Head-tail radio galaxies are characterized by a head, corresponding to an elliptical galaxy, and two radio jets sweeping back from the head, forming an extended structure behind the host galaxy that is moving through the intracluster medium (ICM). This morphology arises from the interaction between the diffuse radio-emitting plasma and the surrounding environment. Sometimes revived fossil plasma is found in galaxy clusters, tracing old active galactic nucleus ejecta with a very steep spectrum re-energized through processes in the ICM, unrelated to the progenitor galaxy. We aim to study the central region of Abell 1775, a galaxy cluster in an unclear dynamical state at z = 0.072. It hosts two giant radio-loud elliptical galaxies, the head-tail radio galaxy that "breaks" at the position of a cold front detected in the X-rays, filamentary revived fossil plasma, and central diffuse emission. This study aims to investigate and constrain the spectral properties and trends along the head-tail, as well as the revived fossil plasma, to better understand the formation process of the non-thermal phenomena in A1775. We make use of LOFAR (144 MHz), and new deep uGMRT observations (400 and 650 MHz). We observe an overall steepening along the tail of the head-tail radio galaxy. In the radio colour-colour diagram, ageing models reproduce the emission of the head-tail. An unexpected brightness increase at the head of the tail suggests a complex bending of the jets. We derived the equipartition magnetic field and minimum pressure along the tail. We recovered the structure of the revived fossil plasma, which appears as thin filaments with ultra-steep spectra. We show that high-sensitivity, high-resolution observations at low frequencies are essential for detecting the full extent of the tail, enabling a deeper spectral analysis and resolving the structure and spectral properties of revived fossil plasma.

Stephen J. Godfrey, Mark Bennett, Victor J. Perez

Although there is now good representation of shark-bitten bone in the fossil record, shark-bitten shark teeth are still exceedingly rare. A relatively small number of teeth of the Neogene megatooth shark Otodus megalodon (Otodontidae) preserve surface markings that were made when struck by the serrated cutting edge of another O. megalodon tooth. The serration marks are consistent with those of the ichnotaxon Knethichnus parallelum. That these shallowly penetrating surface trace fossils were made as one O. megalodon tooth struck another is confirmed by the preservation of fine parallel gouges made when the serrated cutting edge of one tooth impacted and raked the surface of the receiving tooth. The K. parallelum marks on O. megalodon teeth could have been unintentionally self-inflicted, the result of one tooth striking another in the opposing jaw during forceful occlusion, collateral damage from feeding, or aggressive O. megalodon- on-O. megalodon facial biting (i.e., either from active predatory cannibalism, a feeding frenzy during scavenging, or as a result of a territorial dispute to establish a feeding hierarchy).

Comité Organizador de las XXXVII JAPV

Libro de resúmenesde las XXXVII Jornadas Argentinas de Paleontología de Vertebrados, que tuvo lugar en la Ciudad de Corrientes (Corrientes, Argentina) del 14 al 17 de Mayo de 2024.

Yi-Wei Hu, Qiang Li, Jun Liu

Abstract After the devastating Permo-Triassic Mass Extinction, several new groups of large reptilian predators invaded the sea in the early part of the Triassic. Among these predators, sauropterygians, consisting of placodonts, pachypleurosaurs, nothosaurs and pistosaurs (including the iconic plesiosaurs), displayed the greatest diversity at both the generic and species levels, and persisted from the Early Triassic to the Late Cretaceous. Here, we report a new species of Pachypleurosauria, Dianmeisaurus mutaensis sp. nov., from a recently discovered Lagerstätte in the Upper Member of the Anisian Guanling Formation. The only known specimen of the new species was collected from a quarry near Muta village, Luxi County, Yunnan Province, South China. Our new phylogenetic analysis based on a novel data matrix recovered the new taxon as a sister group to Dianmeisaurus gracilis—a small pachypleurosaur from the Middle Triassic Luoping biota. The new phylogenetic analysis also collapsed the monophyly of the traditionally recognized Eusauropterygia. Pistosauroidea, Majiashanosaurus, and Hanosaurus comprise the consecutive sister groups to a new clade including Pachypleurosauria and Nothosauroidea. A monophyletic Pachypleurosauria, within which the clade consisting of Dianmeisaurus and Panzhousaurus occupies the basal-most position, is recovered by this study. The clade consisting of Dawazisaurus and Dianopachysaurus forms the sister group to the remaining pachypleurosaurs included in this study. Since Dianmeisaurus, Panzhousaurus, Dawazisaurus, and Dianopachysaurus are all exclusively known from South China, our study provides further evidence to the hypothesis that pachypleurosaurs had a palaeobiogeographic origin in the eastern Tethys. ZooBank LSID: urn:lsid:zoobank.org:pub:83D12411-9189-4313-A8F0-27AF61BDA51E.

Andrea Prino, Florian Witzmann, Achim H. Schwermann et al.

Temnospondyli appeared in the early Carboniferous, became extinct in the Early Cretaceous and reached high diversity especially during the Permian and Triassic. After the end-Permian mass extinction, almost only Stereospondyli survived (with the exception of the dissorophoid Micropholis). This clade radiated and gave rise to several successful groups: Plagiosauroidea, Trematosauroidea, Metoposauroidea, Capitosauria, and Brachyopoidea. While Brachyopoidea survived into the Early Cretaceous, the other groups were thought to have gradually disappeared during the Late Triassic, going extinct before the Rhaetian. This hypothesis was supported by the lack of unambiguously dated Rhaetian localities with Stereospondyli fossils. This gap was filled by the discovery of the Bonenburg clay pit in North Rhine-Westphalia (Germany). This locality has been unequivocally dated to the late middle Rhaetian and had yielded a temnospondyl fossil assigned to Capitosauria. Here we describe further Stereospondyli fossils from Bonenburg, including diagnostic bones such as a dentary, a pterygoid, a parietal, and eight other bones in different states of preservation. These fossils belong to at least two taxa of Capitosauria and one taxon of Plagiosauridae and represent the geologically youngest remains of both clades. The specimens are described morphologically, and for the long bones, a clavicle fragment, and an unidentified dermal bone, histological analysis was used to further confirm the morphological analysis. These results shed light on the extinction of two major groups of Stereospondyli, documenting that some non-brachyopoid temnospondyls survived until the end of the Triassic.

Louis Annabi, Ziqi Ma, Sao Mai Nguyen

This early-stage research work aims to improve online human-robot imitation by translating sequences of joint positions from the domain of human motions to a domain of motions achievable by a given robot, thus constrained by its embodiment. Leveraging the generalization capabilities of deep learning methods, we address this problem by proposing an encoder-decoder neural network model performing domain-to-domain translation. In order to train such a model, one could use pairs of associated robot and human motions. Though, such paired data is extremely rare in practice, and tedious to collect. Therefore, we turn towards deep learning methods for unpaired domain-to-domain translation, that we adapt in order to perform human-robot imitation.

Sara Kaszuba, Sandeep Reddy Sabbella, Francesco Leotta et al.

In recent years, an increasing number of Human-Robot Interaction (HRI) approaches have been implemented and evaluated in Virtual Reality (VR), as it allows to speed-up design iterations and makes it safer for the final user to evaluate and master the HRI primitives. However, identifying the most suitable VR experience is not straightforward. In this work, we evaluate how, in a smart agriculture scenario, immersive and non-immersive VR are perceived by users with respect to a speech act understanding task. In particular, we collect opinions and suggestions from the 81 participants involved in both experiments to highlight the strengths and weaknesses of these different experiences.

Deja Workman, Christopher L. Dancy

In this paper we hope to identify how the typical or standard artificial intelligence development process encourages or facilitates the creation of racialized technologies. We begin by understanding Sylvia Wynter's definition of the biocentric Man genre and its exclusion of Blackness from humanness. We follow this with outlining what we consider to be the typical steps for developing an AI-based technology, which we have broken down into 6 stages: identifying a problem, development process and management tool selection, dataset development and data processing, model development, deployment and risk assessment, and integration and monitoring. The goal of this paper is to better understand how Wynter's biocentric Man is being represented and reinforced by the technologies we are producing in the AI lifecycle and by the lifecycle itself; we hope to identify ways in which the distinction of Blackness from the "ideal" human leads to perpetual punishment at the hands of these technologies. By deconstructing this development process, we can potentially identify ways in which humans in general have not been prioritized and how those affects are disproportionately affecting marginalized people. We hope to offer solutions that will encourage changes in the AI development cycle.

Weizi Liu

With the rise of human-machine communication, machines are increasingly designed with humanlike characteristics, such as gender, which can inadvertently trigger cognitive biases. Many conversational agents (CAs), such as voice assistants and chatbots, default to female personas, leading to concerns about perpetuating gender stereotypes and inequality. Critiques have emerged regarding the potential objectification of females and reinforcement of gender stereotypes by these technologies. This research, situated in conversational AI design, aims to delve deeper into the impacts of gender biases in human-CA interactions. From a behavioral and communication research standpoint, this program focuses not only on perceptions but also the linguistic styles of users when interacting with CAs, as previous research has rarely explored. It aims to understand how pre-existing gender biases might be triggered by CAs' gender designs. It further investigates how CAs' gender designs may reinforce gender biases and extend them to human-human communication. The findings aim to inform ethical design of conversational agents, addressing whether gender assignment in CAs is appropriate and how to promote gender equality in design.

Christine P Lee

My research centers on the development of context-adaptive AI systems to improve end-user adoption through the integration of technical methods. I deploy these AI systems across various interaction modalities, including user interfaces and embodied agents like robots, to expand their practical applicability. My research unfolds in three key stages: design, development, and deployment. In the design phase, user-centered approaches were used to understand user experiences with AI systems and create design tools for user participation in crafting AI explanations. In the ongoing development stage, a safety-guaranteed AI system for a robot agent was created to automatically provide adaptive solutions and explanations for unforeseen scenarios. The next steps will involve the implementation and evaluation of context-adaptive AI systems in various interaction forms. I seek to prioritize human needs in technology development, creating AI systems that tangibly benefit end-users in real-world applications and enhance interaction experiences.

Laura Miotti, Mónica Salemme

Se presenta un panorama histórico de la trayectoria científica y académica de, al menos, dos disciplinas que desde fines del siglo XIX trataron conjuntamente la cuestión de los paleoambientes y su transformación a partir de la presencia humana. Esta práctica inter y multidisciplinaria fue consolidándose en el Museo de La Plata como la línea de investigación zooarqueológica que hoy tiene gran desarrollo no solo en el país, sino en el mundo. En esta extensa historia académica, las ideas propuestas por Florentino Ameghino hasta las de la actualidad han sido puestas a prueba continuamente. La meta es exponer los principales conceptos vistos desde la producción interdisciplinaria de biólogos y arqueólogos en las regiones pampeana y patagónica.

Aivin V. Solatorio

Predicting human mobility holds significant practical value, with applications ranging from enhancing disaster risk planning to simulating epidemic spread. In this paper, we present the GeoFormer, a decoder-only transformer model adapted from the GPT architecture to forecast human mobility. Our proposed model is rigorously tested in the context of the HuMob Challenge 2023 -- a competition designed to evaluate the performance of prediction models on standardized datasets to predict human mobility. The challenge leverages two datasets encompassing urban-scale data of 25,000 and 100,000 individuals over a longitudinal period of 75 days. GeoFormer stands out as a top performer in the competition, securing a place in the top-3 ranking. Its success is underscored by performing well on both performance metrics chosen for the competition -- the GEO-BLEU and the Dynamic Time Warping (DTW) measures. The performance of the GeoFormer on the HuMob Challenge 2023 underscores its potential to make substantial contributions to the field of human mobility prediction, with far-reaching implications for disaster preparedness, epidemic control, and beyond.

Zheng Yuan, Hongyi Yuan, Chuanqi Tan et al.

Reinforcement Learning from Human Feedback (RLHF) facilitates the alignment of large language models with human preferences, significantly enhancing the quality of interactions between humans and models. InstructGPT implements RLHF through several stages, including Supervised Fine-Tuning (SFT), reward model training, and Proximal Policy Optimization (PPO). However, PPO is sensitive to hyperparameters and requires multiple models in its standard implementation, making it hard to train and scale up to larger parameter counts. In contrast, we propose a novel learning paradigm called RRHF, which scores sampled responses from different sources via a logarithm of conditional probabilities and learns to align these probabilities with human preferences through ranking loss. RRHF can leverage sampled responses from various sources including the model responses from itself, other large language model responses, and human expert responses to learn to rank them. RRHF only needs 1 to 2 models during tuning and can efficiently align language models with human preferences robustly without complex hyperparameter tuning. Additionally, RRHF can be considered an extension of SFT and reward model training while being simpler than PPO in terms of coding, model counts, and hyperparameters. We evaluate RRHF on the Helpful and Harmless dataset, demonstrating comparable alignment performance with PPO by reward model score and human labeling. Extensive experiments show that the performance of RRHF is highly related to sampling quality which suggests RRHF is a best-of-n learner. Codes available at https://github.com/GanjinZero/RRHF.