bioRxiv - Paleontology最新文献

{"title":"Origin of division of labor is decoupled from polymorphism in colonial animals","authors":"Sarah Leventhal, Stewart M Edie, Carl Simpson, Rebecca Morrison","doi":"10.1101/2024.07.05.602267","DOIUrl":"https://doi.org/10.1101/2024.07.05.602267","url":null,"abstract":"Division of labor, the specialization of sometimes phenotypically divergent cell types or group members, is often associated with ecological success in eukaryotic colonial organisms. Despite its many independent evolutionary origins, how division of labor originates remains unclear. Conventional hypotheses tend towards an 'economic' model, so that biological division of labor may reflect a partitioning of pre-existing tasks and morphologies into specialized colony members. Here, we present an alternative model of the origin of division of labor, which can explain the evolution of new functions within a colony. We show that in colonies of the Cretaceous aged (103-96 Ma) fossil bryozoan of the genus Wilbertopora, the first cheilostome bryozoan to evolve polymorphism, new member morphologies were not a simple partitioning of pre-existing morphologies, but instead expanded into novel morphospace as they lost functions, specifically feeding. This expansion into new morphologies occurred primarily during two pulses of heightened morphological disparity, suggesting that the evolution of polymorphism corresponded to relaxed constraints on morphology and perhaps to the exploration of novel functions. Using a simple model of physiological connections, we show that regardless of the functionality of these new colony members, all non-feeding members could have been supported by neighboring feeding members. This suggests that the geometric constraints and physiological connectedness could be prerequisites for evolving both polymorphism and division of labor in modular organisms, and that a classic partitioning model of specialization cannot be broadly applied to biological systems.","PeriodicalId":501477,"journal":{"name":"bioRxiv - Paleontology","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141584882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Portrait of a Young Fish: Redescription of Pteronisculus gunnari (Nielsen, 1942) from a juvenile specimen from the Early Triassic of East Greenland, with implications for ontogenetic development in early actinopterygians","authors":"Iacopo Cavicchini, Thodoris Argyriou, Sam Giles","doi":"10.1101/2024.07.06.598961","DOIUrl":"https://doi.org/10.1101/2024.07.06.598961","url":null,"abstract":"The Early-Middle Triassic actinopterygian genus Pteronisculus (White, 1933) is part of the Triassic Early Fish Fauna (TEFF), a cosmopolitan group of taxa that thrived in the aftermath of the end-Permian mass extinction. Pteronisculus is considered an important non-neopterygian outgroup taxon in many works dealing with the interrelationships of early crown actinopterygians, but the phylogenetic relationships of many of TEFF genera are debated, with the topology of the lineages giving rise to crown actinopterygians consequently unclear. This is despite exceptional, three-dimensionally preservation of an abundance of fossils associated with TEFF fishes. P. gunnari, from the Induan (Early Triassic) Kap Stosch Formation, East Greenland, is known in less detail than other species of the genus. Here, we use X-ray micro-computed tomography to comprehensively redescribe the three-dimensionally preserved holotype of P. gunnari, including a detailed description of the internal anatomy. The specimen shows morphological features previously undescribed for the genus, including paired premaxillae, medially-directed teeth on the palate, canals for the buccohypophysial canal and internal carotids piercing the parasphenoid, and numerous parotic toothplates. Scale covering is complete, but the braincase and palatoquadrate are ossified as multiple elements, indicating that the specimen was not fully mature and allowing new insights into ossification patterns and ontogenetic development of non-neopterygian actinopterygians. These new anatomical data enrich our understanding of both the morphological complexity and the interrelationships of actinopterygians from the Triassic Early Fish Fauna.","PeriodicalId":501477,"journal":{"name":"bioRxiv - Paleontology","volume":"366 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141567371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Basal Cambrian soft-bodied segmented bilaterians preserved as microbial pseudomorphs","authors":"Xiaoguang Yang, Deng Wang, Zhiliang Zhang, Xing Wang, Jie Sun, Wenjing Hao, Yiqun Liu, Kentaro Uesugi, Tsuyoshi Komiya, Jian Han","doi":"10.1101/2024.07.03.601876","DOIUrl":"https://doi.org/10.1101/2024.07.03.601876","url":null,"abstract":"Before Cambrian Stage 3, unambiguous body fossils of segmented bilaterians were rare, severely hampering our understanding of the early history of such important animals. Here we report a variety of microfossils with quintessential features such as paired appendages, dorsoventral and anteroposterior differentiations from the basal Cambrian Fortunian of South China, representing the earliest known three-dimensional body fossils of segmented bilaterians. These fossils were all microbial pseudomorphs built up by secondarily phosphatized bacteria aggregations, testifying microbial pseudomorph could serve as a novel and important pathway to preserve tiny, fragile bilaterian progenitors. This finding unveils a diversified segmented bilaterian world at the very beginning of Cambrian and would arouse a more comprehensive perspective on the early evolution of bilaterian body plans.","PeriodicalId":501477,"journal":{"name":"bioRxiv - Paleontology","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141567372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The relationship between microbial community succession, decay, and anatomical character loss in non-biomineralised animals","authors":"Thomas Clements, Robert Goodall, Sarah Gabbott, Duncan Murdock, Martha Clokie, Andrew Millard, Christopher Turkington, Orla Bath-Enright, Mark A Purnell","doi":"10.1101/2024.07.01.601543","DOIUrl":"https://doi.org/10.1101/2024.07.01.601543","url":null,"abstract":"A fundamental assumption of hypothesis-driven decay experiments is that, during decay, the loss of anatomy follows a sequence broadly controlled by the intrinsic compositional properties of tissues. Recent work investigating the succession of postmortem endogenous microbial communities (thanatomicrobiome) challenges this assumption. These studies suggest the thanatomicrobiome exhibits a predictable, clock-like succession in response to physical and chemical environmental changes within a carcass. Therefore, it is possible that reproducible sequences of character loss during decay are controlled by thanatomicrobiome succession dynamics. If so, exceptionally preserved fossil anatomy would reflect a succession of ancient contemporaneous microbial communities, about which we know nothing, rendering decay experiments uninformative. Here, we investigate two questions: (1) what is the role of exogenous and endogenous bacteria during formation of the thanatomicrobiome and (2) do thanatomicrobiome successions control the sequence of anatomical character loss within a decaying carcass? Our analysis shows that the thanatomicrobiome is dominated by endogenous bacteria and that, even in the presence of inoculum, exogenous bacteria do not invade the carcass and replace native bacteria (while the carcass is intact). This confirms that the use of environmental inoculum in decay experiments introduces an inadvisable confounding variable. Secondly, we find no correlation between thanatomicrobiome successions and the sequence of anatomical character loss, supporting that fossil non-biomineralised characters correlate with their propensity to decay in extant relatives. These findings indicate that the inability to model ancient bacteria does not invalidate decay experiments. We also present a synthesis of the role of bacteria in non-biomineralised fossilisation.","PeriodicalId":501477,"journal":{"name":"bioRxiv - Paleontology","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141552647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New soft tissue data of pterosaur tail vane reveals sophisticated, dynamic tensioning usage and expands its evolutionary origins","authors":"Natalia Jagielska, Thomas G. Kaye, Michael B. Habib, Tatsuya Hirasawa, Michael Pittman","doi":"10.1101/2024.07.01.601487","DOIUrl":"https://doi.org/10.1101/2024.07.01.601487","url":null,"abstract":"Pterosaurs were the first vertebrates to achieve powered flight. Early pterosaurs had long stiff tails with a mobile base that could shift their center of mass, potentially benefiting flight control. These tails ended in a tall, thin soft tissue vane that would compromise aerodynamic control and efficiency if it fluttered during flight like a flag in the wind. Maintaining stiffness in the vane would have been crucial in early pterosaur flight, but how this was achieved has been unclear, especially since vanes were lost in later pterosaurs and are absent in birds and bats. Here we use Laser-Stimulated Fluorescence imaging to reveal a cross-linking lattice within the tail vanes of early pterosaurs. The lattice supported a sophisticated dynamic tensioning system used to maintain vane stiffness, allowing the whole tail to augment flight control and the vane to function as a display structure.","PeriodicalId":501477,"journal":{"name":"bioRxiv - Paleontology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141552648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sponges of the Lower Greensand Group (Lower Cretaceous) of England; a revision","authors":"Consuelo Sendino, Stephen Kershaw","doi":"10.1101/2024.06.28.601142","DOIUrl":"https://doi.org/10.1101/2024.06.28.601142","url":null,"abstract":"Sponges of the Lower Greensand Group (LGS) are well preserved, and occur in sediments of a sandy matrix. Abundant in the Faringdon Sponge Gravel Member (FSG), these sponges, mostly Calcareans are found in Oxfordshire, with notable preservation at Little Coxwell quarries. Classical researchers described sponges and spicules from the LGS, including Lhuyd (considered to have been the first to publish illustrations of LGS sponges), Sharpe, Sowerby and Parkinson. In addition to the FSG, the Folkestone, Hythe, and Atherfield Clay formations within the LGS also contain sponge remains, including spicules as well as whole sponge fossils. These sponges include mostly samples from traditional sponge class Calcarea and a taxon of Hexactinellida; Altogether, the sponge assemblage developed in warm seas of the Lower Cretaceous, and display diverse shapes of sponge bodies and robust spicules. This study provides descriptions of common species following updated Porifera classification and recent sponge taxonomy research, illustrated with specimens from the Natural History Museum, London (NHM) and British Geological Survey (BGS) collections. The following taxa are recorded and described: 1) Calcareans: Barroisia anastomosans (Parkinson, 1811), Barroisia clavata (Keeping, 1883), Barroisia irregularis (Hinde, 1884), Dehukia crassa (de Fromentel, 1861), [Elasmoierea] faringdonensis (Mantell, 1854), [Elasmoierea] mantelli (Hinde, 1884), Peronidella gillieroni (Loriol, 1869), Peronidella prolifera (Hinde, 1884), Peronidella ramose (Roemer, 1839), Oculospongia dilatate (Roemer, 1864), Tremospongia pulvinaria (Goldfuss, 1826), Raphidonema contortum (Hinde, 1884), Raphidonema porcatum (Sharpe, 1854), Raphidonema farringdonensis (Sharpe, 1854), Raphidonema macropora (Sharpe, 1854), Raphidonema pustulatum Hinde, 1884, Endostoma foraminosa (Goldfuss, 1829); 2) Hexactinellids: Lonsda contortuplicata Lonsdale, 1849.","PeriodicalId":501477,"journal":{"name":"bioRxiv - Paleontology","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141512167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Devonian stromatoporoid historical collections in the Natural History Museum, London (UK): redescription, taxonomic revision and implications for stromatoporoid global paleobiogeography","authors":"Jiayuan Huang, Consuelo Sendino, Stephen Kershaw","doi":"10.1101/2024.06.30.601411","DOIUrl":"https://doi.org/10.1101/2024.06.30.601411","url":null,"abstract":"Devonian stromatoporoid collections in the Natural History Museum, London (UK) have been deposited for over 100 years. The characteristics and systematic position of these specimens, however, have received little attention. In this study, a total of 307 Devonian stromatoporoid specimens comprising material documented by Nicholson (1886 to 1892) from the UK, Germany, United States, and Canada, plus specimens described by Ripper (1933, 1937a, b, c) from Australia, were re-examined. Overall, 50 species belonging to 29 genera were systematically redescribed based on recent progress, mainly including Actinostroma, Petridiostroma, Stictostroma, Pseudotrupetostroma, Parallelopora. Three-dimensional reconstructions of the type genus are illustrated following the earlier works of Stearn (1966) and Cockbain (1984). The reconstructed skeletons reveal stromatoporoid architectural patterns, crucial for enhancing understanding and revision of stromatoporoid identification. This study underscores the significance of three-dimensional reconstruction in taxonomic research on stromatoporoid. The NHMUK material is combined with data from publications and the Paleobiology Database (PBDB) to perform a network analysis of the global occurrence of Devonian stromatoporoids at the generic level; this reveals a close relationship of global stromatoporoid fauna during the Early Devonian, indicating a widespread distribution, despite this interval being regarded as a time of global stromatoporoid contraction. The Middle Devonian assemblage shows a much higher cosmopolitan occurrence in the context of the subsequent Eifelian-Givetian global stromatoporoid proliferation, consistent with the known pattern from other studies of Middle Devonian stromatoporoids. Overall, the NHMUK collections are a valuable resource to help understand the global occurrence of Devonian stromatoporoids.","PeriodicalId":501477,"journal":{"name":"bioRxiv - Paleontology","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141512305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling of Rate Heterogeneity in Datasets Compiled for Use With Parsimony","authors":"April M Wright, Brenen M Wynd","doi":"10.1101/2024.06.26.600858","DOIUrl":"https://doi.org/10.1101/2024.06.26.600858","url":null,"abstract":"In recent years, there has been an increased interest in modeling morphological traits using Bayesian methods. Much of the work associated with modeling these characters has focused on the substitution or evolutionary model employed in the analysis. However, there are many other assumptions that researchers make in the modeling process that are consequential to estimated phylogenetic trees. One of these is how among-character rate variation (ACRV) is parameterized. In molecular data, a discretized gamma distribution is often used to allow different characters to have different rates of evolution. Morphological data are collected in ways that fundamentally differ from molecular data. In this paper, we appraise the use of standard parameters for ACRV and provide recommendations to researchers who work with morphological data in a Bayesian framework.","PeriodicalId":501477,"journal":{"name":"bioRxiv - Paleontology","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141512168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolutionary paleoecology of European rhinocerotids across the Oligocene-Miocene transition","authors":"Manon Hullot, Celine Martin, Cecile Blondel, Damien Becker, Gertrud E Roessner","doi":"10.1101/2024.04.17.589495","DOIUrl":"https://doi.org/10.1101/2024.04.17.589495","url":null,"abstract":"The Oligocene-Miocene transition witnessed great environmental and faunal changes, but its drivers and consequences on mammals remain poorly understood. Rhinocerotoids are among the most affected taxa, reflected by great taxonomical (extinction of all non-rhinocerotids) and morphological (e.g., more mediportal forms) changes observed during this interval. However, potential associated changes in ecology have not been explored. Here, we investigated the paleoecology of 10 rhinocerotid species coming from 15 localities across Western and Central Europe and ranging from Mammal Paleogene reference level 28 to Mammal Neogene zone 3. We explored evolutionary trends for their diet, physiology, and habitat via dental wear, hypoplasia, body mass estimates, and stable isotopy. Our results (isotopy, dental wear) suggest that all rhinocerotids studied were C3 feeders, whether browsing or mixed-feeding, but niche partitioning was assumed at some localities: distinct dietary preferences and/or habitats were highlighted at Gaimersheim, Ulm-Westtangente, and Rickenbach, whereas a potential competition for the resources or different niche partitioning strategies (body mass, feeding height) are hypothesized at others localities (La Milloque, Thezels, Paulhiac). We reconstructed similar warm conditions at all localities except Gaimersheim, but found greater variations in precipitation. Indeed, a clear shift in delta13CCO3, enamel values was noticed at the end of the Oligocene, consistent with climatic changes (Mi-1) and vegetation modifications reported at that time. Despite these great changes, the prevalence of hypoplasia was low (< 10 %) to moderate (< 20 %) except at some localities (Pappenheim, Rickenbach, Engehalde) and for some species (Brachydiceratherium aurelianense and B. lamilloquense). Teleoceratines were particularly affected, suggesting a potential phylogenetic effect. Fourth milk molars and third molars were the most affected loci, indicating stresses around birth and environmental stresses respectively. Body mass co-variated with hypoplasia prevalence, indicating that larger species might be more susceptible to stresses and environmental changes. The tracking of rhinocerotids paleoecological preferences during the Oligocene-Miocene revealed several changes in diet and habitat (temperature, precipitation, vegetation) consistent with global changes during this period.","PeriodicalId":501477,"journal":{"name":"bioRxiv - Paleontology","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140625196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative Models for Distinguishing Punctuated and Continuous-Time Models of Character Evolution and Their Implications for Macroevolutionary Theory","authors":"April M Wright, Peter J. Wagner","doi":"10.1101/2024.04.09.588788","DOIUrl":"https://doi.org/10.1101/2024.04.09.588788","url":null,"abstract":"The recent proliferation of quantitative models for assessing anatomical character evolution all assume that character change happens continuously through time. However, punctuated equilibrium model posits that character change should be coincide with cladogenetic events, and thus should be tied to origination rates. Rates of cladogenesis are important to quantitative phylogenetics, but typically only for establishing prior probabilities of phylogenetic topologies. Here, we modify existing character likelihood models to use the local cladogenesis rates from Bayesian analyses to generate the amounts of character change over time dependent on origination rates, as expected under the punctuated equilibrium model. In the case of strophomenoid brachiopods strop from the Ordovician, we find that Bayesian analyses strongly favor punctuated models over continuous-time models, with elevated rates of cladogenesis early in the clade's history inducing frequencies of change despite constant rates of change per speciation event. This corroborates prior work proposing that the early burst in strophomenoid disparity reflects simply elevated speciation rates, which in turn has implications for seemingly unrelated macroevolutionary theory about whether early bursts reflect shifts in intrinsic constraints or empty ecospace. Future development of punctuated character evolution models should account for the full durations of species, which will provide a test of continuous change rates. Ultimately, continuous change vs. punctuated change should become part of phylogenetic paleobiology in the same way that other tests of character evolution currently are.","PeriodicalId":501477,"journal":{"name":"bioRxiv - Paleontology","volume":"57 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140600898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}