Hasil untuk "Fossil man. Human paleontology"

Cynthia M. Baseman, Myeonghan Ryu, Nathaniel Swinger et al.

Psychotherapy delivery relies on a negotiation between patient self-reports and clinical intuition. Growing evidence for technological support of psychotherapy suggests opportunities to aid the mediation of this tension. To explore this prospect, we designed a prototype of a clinical decision support system (CDSS) for treating veterans with post-traumatic stress disorder in a Prolonged Exposure (PE) therapy intensive outpatient program. We conducted a two-phase interview study to collect perspectives from practicing PE clinicians and former PE patients who are United States veterans. Our analysis distills opportunities for a CDSS (e.g., offering homework review at a glance, aiding patient conceptualization) and larger challenges related to context and deployment (e.g., navigating Veterans Affairs). By reframing our findings through three human-centered perspectives (distributed cognition, situated learning, infrastructural inversion), we highlight the complexities of designing a CDSS for psychotherapists in this context and offer theory-aligned design considerations.

Andrej Čerňanský, Georgios L. Georgalis, Maeva J. Orliac et al.

Reptile faunas from the late middle Eocene of Europe are rare. Here, we report on lizards, snakes, turtles and crocodiles from the Lavergne locality in the Quercy Region (France). Reptiles here are diverse, represented by (at least) 16 taxa. Lizard assemblage consists of Gekkota, Pleurodonta, Scincidae, Lacertidae, Glyptosauridae, Anguidae and Palaeovaranidae. Snakes are represented by the enigmatic alethinophidian Platyspondylia sudrei, the ?tropidophiid Cadurceryx filholi, the pythonoid Palaeopython cadurcensis, the booids ?Eoconstrictor sp. and Dunnophis cadurcensis, an indeterminate potential russellophiid, whereas several remains are only identified as indeterminate alethinophidians. Besides squamates, Testudinoidea and Crocodylia are also present; because of the extreme rareness of the latter group in the Quercy area, we also describe here some additional crocodylian specimens from the “old collections” of Quercy. Scincids are firstly reported from Lavergne, including a new taxon, Lavergnesaurus lamarcki gen. et sp. nov. The fauna indicates a relatively warm temperature as demonstrated by thermophilic taxa. Lavergne yields a relatively similar (not identical) herpetofauna as Le Bretou (France) and Mazaterón (Spain). However, Lavergne and Le Bretou appear to be, based on current knowledge, more similar to each other when lizards and snakes are considered. Overall, the European MP 16 squamate fauna does not seem to be highly different from those of MP 14 or MP 17 and no faunal reorganisation or any significant extinction event can be recognised at the middle – late Eocene boundary in Europe. In fact, larger faunal changes are recognisable when early Eocene herpetofaunas are considered.

XU Xing-Dong, SHI Qin-Qin

Antilospira is a small to medium-sized antelope with heteronymously spiraled horn cores. It was widely distributed in northern China from the Late Pliocene to the Early Pleistocene. It is a typical fossil bovid with important implications for biostratigraphy and antilopin evolution in China. Antilospira robusta is a species with highly fragmentary materials and has previously only been briefly discussed. Here we report on a new frontal with horn cores from the Early Pleistocene Wucheng Loess in Nalesi Township, Dongxiang Autonomous County, Linxia Basin, Gansu Province. This new material features heteronymously spiraled horn cores, deep longitudinal grooves, a sharp anterior carena on the horn core, and a large body size, which are characteristics similar to those of A. robusta. However, the horn base of the new material is more compressed than all the previously discovered spiral-horned antelopes, so we attributed it to Antilospira cf. A. robusta. This is the first time Antilospira has been found in northwestern China, and this discovery provides more morphological data for the classification of this group. CT scans of the horn core reveal the well-remodeled horn core trabeculae in Antilospira, which is different from what is observed in Spirocerus. The frontal sinuses are moderately developed in the Linxia specimen, extending backwards to the orbit but not to the horn base. The virtual reconstruction of the endocranial cast indicated that Antilospira has bending and narrow frontal lobes, wide temporal lobes, and relatively complex sulci on the cerebral hemisphere, which differ from extant Antilopini bovids in China.

Sergio M. Nebreda, Luis M. Chiappe, Guillermo Navalón et al.

The fossil record of Early Cretaceous enantiornithine birds from the Iberian Peninsula is the most significant in the world outside of China. Despite its historical relevance, taxonomic diversity, and relative abundance, adult cranial remains had not been reported before. In this study, we describe a new enantiornithine species, Gorgonavis alcyone gen. et sp. nov. based on a disarticulated skull from the Early Cretaceous locality of Las Hoyas (129–126 Myr; Cuenca, Spain), the first adult cranial remains of a bird from this fossil site. Digital imaging of the µCT-scanned fossil remains shows that Gorgonavis is characterized by a slender and elongated rostrum in which teeth are restricted to the premaxillary corpus, a thin, edentulous maxilla, and a jugal bone with an elongated and strongly angled postorbital process. Despite the fragmentary nature of the holotype, comparative anatomy and phylogenetic analyses suggest the identification of the new species as a longipterygid, a distinct clade of Enantiornithes characterised by an elongated rostrum, a cranial configuration consistent with the new fossil. Gorgonavis represents the oldest occurrence of an enantiornithine with relative rostral elongation outside of the Jehol Biota. The new discovery suggests that some specialised early enantiornithine lineages had a broader geographical, and more ecologically diverse distribution than previously thought.

Xuyang Zhu, Sejoon Chang, Andrew Kuik

Retrieval-Augmented Generation (RAG) systems offer a powerful approach to enhancing large language model (LLM) outputs by incorporating fact-checked, contextually relevant information. However, fairness and reliability concerns persist, as hallucinations can emerge at both the retrieval and generation stages, affecting users' reasoning and decision-making. Our research explores how tailored warning messages -- whose content depends on the specific context of hallucination -- shape user reasoning and actions in an educational quiz setting. Preliminary findings suggest that while warnings improve accuracy and awareness of high-level hallucinations, they may also introduce cognitive friction, leading to confusion and diminished trust in the system. By examining these interactions, this work contributes to the broader goal of AI-augmented reasoning: developing systems that actively support human reflection, critical thinking, and informed decision-making rather than passive information consumption.

Frederic Gmeiner, Nicolai Marquardt, Michael Bentley et al.

Despite Generative AI (GenAI) systems' potential for enhancing content creation, users often struggle to effectively integrate GenAI into their creative workflows. Core challenges include misalignment of AI-generated content with user intentions (intent elicitation and alignment), user uncertainty around how to best communicate their intents to the AI system (prompt formulation), and insufficient flexibility of AI systems to support diverse creative workflows (workflow flexibility). Motivated by these challenges, we created IntentTagger: a system for slide creation based on the notion of Intent Tags - small, atomic conceptual units that encapsulate user intent - for exploring granular and non-linear micro-prompting interactions for Human-GenAI co-creation workflows. Our user study with 12 participants provides insights into the value of flexibly expressing intent across varying levels of ambiguity, meta-intent elicitation, and the benefits and challenges of intent tag-driven workflows. We conclude by discussing the broader implications of our findings and design considerations for GenAI-supported content creation workflows.

Oliver Chojnowski, Alexander Eberhard, Michael Schiffmann et al.

Socially interactive agents are gaining prominence in domains like healthcare, education, and service contexts, particularly virtual agents due to their inherent scalability. To facilitate authentic interactions, these systems require verbal and nonverbal communication through e.g., facial expressions and gestures. While natural language processing technologies have rapidly advanced, incorporating human-like nonverbal behavior into real-world interaction contexts is crucial for enhancing the success of communication, yet this area remains underexplored. One barrier is creating autonomous systems with sophisticated conversational abilities that integrate human-like nonverbal behavior. This paper presents a distributed architecture using Epic Games MetaHuman, combined with advanced conversational AI and camera-based user management, that supports methods like motion capture, handcrafted animation, and generative approaches for nonverbal behavior. We share insights into a system architecture designed to investigate nonverbal behavior in socially interactive agents, deployed in a three-week field study in the Deutsches Museum Bonn, showcasing its potential in realistic nonverbal behavior research.

Tyler R. Lyson, Holger Petermann, Salvador Bastien et al.

Abstract Isolated pan-chelydrid turtle shell fragments are common in Late Cretaceous and early Paleocene sediments across western North America, but more complete and associated specimens are rare, obfuscating our understanding of the group’s early evolution. Here we describe a new genus and species, Tavachelydra stevensoni, of stem-chelydrid turtle from the early Paleocene of the Denver Formation (Danian, Puercan I and II) of Colorado based on complete shells, associated pelvic material, and referred cranial material. Our phylogenetic analysis places T. stevensoni as the immediate sister to crown chelydrids based on, among others, a purely ligamentous attachment of the plastron and carapace. The costiform process of the nuchal, an important character complex in chelydroid turtles, shows variation in either ending in peripheral II or III. The T. stevensoni material was mostly found in laminated fine-grained deposits, suggesting this taxon inhabited ponded-water environments. The referred cranial material shows broad triturating surfaces indicating a durophagous diet, further underscoring durophagy as an important feeding strategy during the early Paleocene.

Walter G. Joyce

Abstract Soft-shelled turtles (Pan-Trionychidae) are one of the primary clades of turtles with a particularly rich fossil record reaching back to the Early Cretaceous. Yet, the evolution of the group has been difficult to resolve, in part because the fossil record mostly consists of shells and because the shells are known to exhibit high levels of polymorphism, making it difficult to establish parsimony-informative characters. A revision of the shell osteology of extant and extinct pan-trionychid turtles resulted in the development of 69 revised and novel characters with over 221 derived character states. Of these, 40 are multistate characters and 11 morphometric characters that utilize length, surface, and angular measurements. In a first step, the characters were scored for 530 regularly developed individuals representing all currently recognized species of living trionychids. The primary dataset confirms that most characters are affected by high levels of polymorphism. Statistical analyses conclude that much variability can be attributed to ontogenetic changes. In a second step, the primary data was used to code terminal taxa by reference to the most adult individuals for characters controlled by ontogeny. Terminals were otherwise only scored polymorphic if at least 20% of individuals displayed a particular character state. A phylogenetic analysis concludes that the new characters converge best upon the emerging molecular consensus, if characters are run ordered. All three utilized outgroups have a negative impact on ingroup relationships and character evolution, which can only partially be addressed through the use of a molecular backbone. The reduction of polymorphism by reference to adults and a minimum frequency of 20% yields more parsimony-informative characters and character states. A brief account is provided on how to diagnose all extant clades and species of trionychids using osteological characters.

Manuel Amadori, Sanja Japundžić, Jacopo Amalfitano et al.

Abstract A new lower tooth plate of Ptychodus decurrens from the Turonian (Upper Cretaceous) of the Dalmatian region (southern Croatia) is documented here for the first time. The specimen represents the first articulated dentition of a ptychodontid shark that has been discovered from the Balkan Peninsula and the most complete ever found for the un-cuspidate species P. decurrens up to now. The reconstruction of the entire lower dentition of P. decurrens based on this exceptionally well-preserved dentition shows a wider crushing plate than previously hypothesised with bulgy teeth limited to the central area. Even though a defined cusp is missing, the occlusal surface of the teeth is undeniably raised and bulgy in some un-cuspidate species of Ptychodus (e.g., P. decurrens). This compels us to reconsider the use of terms such as high- and low-crowned as well as cuspidate and un-cuspidate. In addition, specimens previously assigned to dubious species (P. depressus, P. levis and P. oweni) or even varieties (P. polygyrus var. sulcatus and P. decurrens var. multiplicatus) are reassigned here to P. decurrens based on a careful comparison of the type materials. The reassessment of tooth root morphologies provides indicative traits for the identification of different genera of ptychodontid sharks (Paraptychodus and Ptychodus). The taxonomic revision presented here is crucial for securing a stable taxonomy and systematics of the shell-crushing shark P. decurrens, as well as of all ptychodontid sharks. The resulting updated taxonomy, together with the description and reconstruction of the new crushing plate, greatly contribute to a better understanding of one of the most enigmatic families (Ptychodontidae) of Mesozoic elasmobranchs. The detailed investigation of the new dentition of Ptychodus from Dalmatia is also a further step towards the discovery of Upper Cretaceous ichthyofaunas of one of the most palaeontologically important areas of the Balkan Peninsula.

Stephen J. Godfrey, Victor J. Perez, Marcus Jones et al.

Recent isotopic analyses of the teeth of the extinct lamnid Carcharodon hastalis showed that it fed at a comparable trophic level as was the fossil and modern great white shark, Carcharodon carcharias. Although there are many examples of shark bite marks on marine mammal bones, there have not been any publications documenting the presence of C. hastalis teeth embedded in the bones of marine mammals. Here we report on the first C. hastalis teeth found embedded in vertebrae of two Miocene cetaceans. These teeth represent unequivocal evidence of trophic interactions between this shark and cetaceans. It is not known if these interactions were the result of active predation or scavenging. These embedded C. hastalis teeth offer supporting evidence to the aforementioned isotopic findings. The finding of C. hastalis teeth embedded in cetacean vertebrae demonstrate that in the Carcharodon lineage, serrated teeth were not a prerequisite to feeding on marine mammals. Carcharodon hastalis may have fed on marine mammals for millions of years prior to the evolution of lightly serrated teeth in its chronospecific descendent, Carcharodon hubbelli. The behavioral adaptation to mammalophagy in the Carcharodon lineage, regardless as to how inefficient it might have been without serrated teeth, appears to have occurred for millions of years prior to the evolution of fully serrated teeth in Carcharodon carcharias. That feeding behavior may well have given natural selection sufficient time to develop and hone the serrated teeth now seen in extant great white sharks (C. carcharias). Given that competition for high trophic resources between the Carcharodon and Otodus lineages seemingly existed for millions of years prior to the extinction of Otodus megalodon, it seems that competition alone is likely not the only explanation for why O. megalodon went extinct.

Liqun Zhao, Keyan Miao, Konstantinos Gatsis et al.

Reinforcement learning (RL) excels in applications such as video games, but ensuring safety as well as the ability to achieve the specified goals remains challenging when using RL for real-world problems, such as human-aligned tasks where human safety is paramount. This paper provides safety and stability definitions for such human-aligned tasks, and then proposes an algorithm that leverages neural ordinary differential equations (NODEs) to predict human and robot movements and integrates the control barrier function (CBF) and control Lyapunov function (CLF) with the actor-critic method to help to maintain the safety and stability for human-aligned tasks. Simulation results show that the algorithm helps the controlled robot to reach the desired goal state with fewer safety violations and better sample efficiency compared to other methods in a human-aligned task.

Wan-Qian Zhao, Zhan-Yong Guo, Zeng-Yuan Tian et al.

High quality ancient DNA (aDNA) is essential for molecular paleontology. Due to DNA degradation and contamination by environmental DNA (eDNA), current research is limited to fossils less than 1 million years old. The study successfully extracted DNA from Lycoptera davidi fossils from the Early Cretaceous period, dating 120 million years ago. Using high-throughput sequencing, 1,258,901 DNA sequences were obtained. We established a rigorous protocol known as the mega screen method. Using this method, we identified 243 original in situ DNA (oriDNA) sequences, likely from the Lycoptera genome. These sequences have an average length of over 100 base pairs and show no signs of deamination. Additionally, 10 transposase coding sequences were discovered, shedding light on a unique self-renewal mechanism in the genome. This study provides valuable DNA data for understanding ancient fish evolution and advances paleontological research.

Ruican Zhong, Donghoon Shin, Rosemary Meza et al.

This paper explores the integration of causal pathway diagrams (CPD) into human-centered design (HCD), investigating how these diagrams can enhance the early stages of the design process. A dedicated CPD plugin for the online collaborative whiteboard platform Miro was developed to streamline diagram creation and offer real-time AI-driven guidance. Through a user study with designers (N=20), we found that CPD's branching and its emphasis on causal connections supported both divergent and convergent processes during design. CPD can also facilitate communication among stakeholders. Additionally, we found our plugin significantly reduces designers' cognitive workload and increases their creativity during brainstorming, highlighting the implications of AI-assisted tools in supporting creative work and evidence-based designs.

Gerald Mayr, Andrew C. Kitchener

We report a tarsometatarsus and an associated pedal phalanx from the lower Eocene London Clay of Walton-on-the- Naze (Essex, UK). The specimen resembles the tarsometatarsus of the taxon Limnofregata (Fregatidae), but it belongs to a species that is distinctly larger than any other, extinct or extant, frigatebird, from which it also differs in some morphological features. Because of a close stratigraphical and geographical provenance, as well as a similar large size and frigatebird-like morphology, we consider it possible that the fossil belongs to Marinavis longirostris. This large seabird was initially described from the London Clay of Abbey Wood and is based on fragments of the rostrum, which likewise show a resemblance to the Fregatidae. If correctly assigned to the Fregatidae, the fossils would be among the earliest records of frigatebirds and the first fossils of this group of birds from the Paleogene of Europe, but we note that our tentative classification is still afflicted with considerable uncertainty.

LUCCA S. CUNHA, PAULA DENTZIEN-DIAS, HEITOR FRANCISCHINI

New bioerosion traces produced by insects in bones are reported from the Hyperodapedon Assemblage Zone of the Santa Maria Supersequence (Carnian, Brazil). The bones are assigned to a single rhynchosaur Hyperodapedon mariensis individual and among the traces, the ichnogenera Osteocallis (Osteocallis mandibulus, Osteocallis infestans, and Osteocallis isp.) and Amphifaoichnus (Amphifaoichnus isp.) are recognized, along with two morphotypes of indiscrete traces: clusters of grooves and borings. All the traces are assigned to the action of insects exploring the rhynchosaur carcass. Osteocallis and associated clusters of grooves are interpreted as feeding traces, but whether they represent necrophagic or osteophagic behavior is still uncertain. The lack of direct evidence for the ethological interpretation of Amphifaoichnus precludes its sole correlation with osteophagy, and other possibilities, such as the construction of temporary domiciles related to feeding or sediment moisture, are discussed. The traces analyzed here indicate that the insects explored a buried carcass, challenging the automatic association of Osteocallis and prolonged subaerial exposure of bones, placing insects as relevant taphonomic agents that affect the preservation of vertebrate carcasses. Additionally, the first appearance record of Amphifaoichnus is expanded back more than 140 Ma, indicating that complex behaviors employed by insects in bone exploration were already established in the early Late Triassic, shortly after the oldest records of invertebrate bioerosion in bones on continental settings.

M. Ashby

Dar-Yen Chen

This paper presents a novel free-hand sketch synthesis approach addressing explicit abstraction control in class-conditional and photo-to-sketch synthesis. Abstraction is a vital aspect of sketches, as it defines the fundamental distinction between a sketch and an image. Previous works relied on implicit control to achieve different levels of abstraction, leading to inaccurate control and synthesized sketches deviating from human sketches. To resolve this challenge, we propose two novel abstraction control mechanisms, state embeddings and the stroke token, integrated into a transformer-based latent diffusion model (LDM). These mechanisms explicitly provide the required amount of points or strokes to the model, enabling accurate point-level and stroke-level control in synthesized sketches while preserving recognizability. Outperforming state-of-the-art approaches, our method effectively generates diverse, non-rigid and human-like sketches. The proposed approach enables coherent sketch synthesis and excels in representing human habits with desired abstraction levels, highlighting the potential of sketch synthesis for real-world applications.

Yi-Shiuan Tung, Matthew B. Luebbers, Alessandro Roncone et al.

Understanding the intentions of human teammates is critical for safe and effective human-robot interaction. The canonical approach for human-aware robot motion planning is to first predict the human's goal or path, and then construct a robot plan that avoids collision with the human. This method can generate unsafe interactions if the human model and subsequent predictions are inaccurate. In this work, we present an algorithmic approach for both arranging the configuration of objects in a shared human-robot workspace, and projecting ``virtual obstacles'' in augmented reality, optimizing for legibility in a given task. These changes to the workspace result in more legible human behavior, improving robot predictions of human goals, thereby improving task fluency and safety. To evaluate our approach, we propose two user studies involving a collaborative tabletop task with a manipulator robot, and a warehouse navigation task with a mobile robot.

Jared Flowers, Marco Faroni, Gloria Wiens et al.

This paper addresses human-robot collaboration (HRC) challenges of integrating predictions of human activity to provide a proactive-n-reactive response capability for the robot. Prior works that consider current or predicted human poses as static obstacles are too nearsighted or too conservative in planning, potentially causing delayed robot paths. Alternatively, time-varying prediction of human poses would enable robot paths that avoid anticipated human poses, synchronized dynamically in time and space. Herein, a proactive path planning method, denoted STAP, is presented that uses spatiotemporal human occupancy maps to find robot trajectories that anticipate human movements, allowing robot passage without stopping. In addition, STAP anticipates delays from robot speed restrictions required by ISO/TS 15066 speed and separation monitoring (SSM). STAP also proposes a sampling-based planning algorithm based on RRT* to solve the spatio-temporal motion planning problem and find paths of minimum expected duration. Experimental results show STAP generates paths of shorter duration and greater average robot-human separation distance throughout tasks. Additionally, STAP more accurately estimates robot trajectory durations in HRC, which are useful in arriving at proactive-n-reactive robot sequencing.